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Hey all -- I'm gathering info for a new project I'm about to embark on: building a multiple-effects unit based entirely on trad, discrete circuits. 

Here's the deal--I have some cheap '60s guitars (3 Danelectros & a Kay Airline) and my main musical thing is based in mid-to-late-'60s psych and sunshine pop.  I certainly can't afford to buy the 15 or so original, vintage boxes that I want, so I'll need to build 'em myself.  And, in the interest of historical accuracy and tone (and because I hate chips), I want to do it all with discrete circuits; no op-amps or ICs.  I'm going to build a single housing for them (about 18" wide, 12" deep and 6" tall) which will straddle the tube amp that I record my guitars with, placing it at waist level for maximum knob twiddling convenience while I set up for recording takes. 

Here's where I need your help.  The effects I want are roughly as follows, along with some examples:

Distortion/fuzz/waveform clipping/whatever--Vox Tone-Bender, Maestro Fuzz-Tone, Heathkit TA-28 or something similar

Treble-booster--maybe the Dallas Rangemaster or E-H Screaming Bird/Tree

Tremolo--Vox, Kay or ?

Ring modulator--Maestro?

Octave generator--Roger Mayer Octavia?

Overdriver--solid-state or simple tube

Chorus

Compressor

Parametric EQ

Bass booster

Sustainer

Attack/Decay
and/or
Auto-wah / envelope follower

Flanger

Phase shifter

Echo (not tape loop-based)

Noise gate

Spring reverb tank

Can anyone recommend effects to copy, or suggest a source for discrete circuit schematics for these effects?  FWIW, I prefer effects that do just one thing, but do it well.  Not fuzz/wah/stereo breath freshner or the like; just fuzz, just wah.  FWIW, I'm pretty handy with a soldering iron.  Thanks for any input.

I would start here: http://www.diystompboxes.com/pedals/schematics.html

just a warning: a phase shifter w/o ICs, is a bitch (thinking univibe). i have yet to see a chorus/flanger w/o ICs, and i am not familiar with a discrete noise gate (but i don't really watch those)

btw, that is a HUGE amount of effects to simply start out for. you will put in hundreds of dollars, and some of your projects don't even look possible. you might want to slow down and think about the discrete plan (so many more options with ICs) and probably tone down your plan to build all of these things.

but, if you really want alot of projects, go to places like

http://www.generalguitargadgets.com/ (http://www.generalguitargadgets.com/)

http://www.tonepad.com/ (http://www.tonepad.com/)

http://fuzzcentral.tripod.com/ (http://fuzzcentral.tripod.com/)

there are many others, but these should get you started...
good luck!

An interestign thing about music 'back then' was, how little effects were used. An advantage of this, ws that when they WERE used, it was pretty high impact. I recommend thinking about whose work you admire & seeig what they used (there aren't many old FX that havn't been recreated).
The earliest compressors were a small amp drivign a small lightbulb, that affected a light dependent resistor in a voltage divider (part of the legedary joe meek sound, but I doubt one was ever used on stage).

>>"just a warning: a phase shifter w/o ICs, is a bitch (thinking univibe). i have yet to see a chorus/flanger w/o ICs"<<

This is exactly the sort of advice I need.  Thanks! 

>>"btw, that is a HUGE amount of effects to simply start out for. you will put in hundreds of dollars..."<<

Yeah--but it's still far less than I'd have to spend to get the effects separately.  I'm not worried about the cost (within reason).  As for the scope of the project...well, I just restored a '60s transistor organ, which included replacing almost 300 caps.  I'm not particularly worried about building 15 effects with an average of 10 or so components each. 

>>"...and some of your projects don't even look possible"<<

Which ones?  Anything beyond the phase-shifter/chorus/flanger you mentioned?  Aren't there choruses that use op-amps?  Isn't an op-amp just a "shortcut" that replaces like 20 transistors and 10 resistors with one component?  If that's the case, I don't mind making the discrete circuit to replace it with.  I *really* don't like chips.

Are there any stompbox websites that are *specifically* about discrete circuit units?  Or arrange them chronologically?

>>"I recommend thinking about whose work you admire & seeig what they used (there aren't many old FX that havn't been recreated)."<<

I'm not trying to re-create anyone's sound, per se.  While I really like the guitar sounds of say, Syd Barrett, Ed King (from Strawberry Alarm Clock), early Steve Hillage and Steve Hackett, I'm not looking to copy them, but rather to use their technology as a stepping-off point for my own experiments. 

>>"The earliest compressors were a small amp drivign a small lightbulb, that affected a light dependent resistor in a voltage divider (part of the legedary joe meek sound, but I doubt one was ever used on stage)."<<

Amazing!  I'm going to go Google that right now! 

Quote from: rch427 on October 06, 2005, 07:27:28 PMYeah--but it's still far less than I'd have to spend to get the effects separately.  I'm not worried about the cost (within reason).

It will cost you the same amount or more to build your own effects in general. You can buy a ready made already working units with the cost of little to no time or build your own effect, which takes time, and have to debug it which takes even more time then building it. It depends on how much you think your time is worth.

Quote from: rch427 on October 06, 2005, 07:27:28 PM
Which ones?  Anything beyond the phase-shifter/chorus/flanger you mentioned?  Aren't there choruses that use op-amps?  Isn't an op-amp just a "shortcut" that replaces like 20 transistors and 10 resistors with one component?  If that's the case, I don't mind making the discrete circuit to replace it with.  I *really* don't like chips.

Me thinks you have fallen prey to the "discrete is better the IC" myth. You should do some more research to understand the differences and reasons for both their exsistance. Then maybe you will also reconsider some of the aspects of your project thus far.

Andrew

 :icon_lol:
You will soon like IC's circuits... I am sure :icon_biggrin:

i trust you don't think a flanger can be built with ten parts... or even a compressor, for that matter.

believe me, you need ICs to do a chorus or flanger. they need either a bucket brigade delay or digital delay to function. creating either out of discrete components is probably not in range of the average DIYer  ;)

there are oilcan delays, and leslie-rotary speakers, but those are mechanical sorts of pedals (and i don't know anything about them at all)

Hmmm...maybe I should present my bona fides:

I bought my first electric guitar and amp in 1978 (an early-'60s Harmony Stratotone and a Silverfaced Fender); the first of at least 9 guitars that I can recall, and maybe a dozen amps.  I've had literally dozens of stompboxes; most of them vintage.  I once had close to 20 Ross effects (including the first series compressor) at the same time.  I know a bit about the way analog effects sound, and I know that I don't like the sound of digital effects, I don't care for the sound of ICs, and I definitely prefer the sound of germanium diodes and transistors, something you can't get with any op-amp, AFAIK. 

>>"It will cost you the same amount or more to build your own effects in general."<<

Oh, c'mon; no it won't.  While I might be able to get an example of of each type of effect, recently made in China out of sardine tins, used, on eBay for around $30 each, they sound like crap.  The *minimum* for a decent-sounding effect--even used--is way more than the components cost to build, say, a replica of an early fuzz box.  Especially considering I'm not putting each one in its own enclosure. 

So, I trust we can bury the cost issue and the "you don't know what things sound like" issue, OK?

Now: how 'bout back to the original question--which of the effects on my shopping list were never made back in the discrete circuit days?  What work-arounds are possible?  Any answers to these sorts of questions is greatly appreciated.

QuoteTreble-booster--maybe the Dallas Rangemaster or E-H Screaming Bird/Tree

Those are your best choices.

QuoteTremolo--Vox, Kay or ?

Use the EA Tremolo. It's the best of the easy non-IC devices.

QuoteRing modulator--Maestro?

Use the two-transformer version of a ring modulator. All the others require ICs or matched transistor arrays, which is the same thing.

QuoteOctave generator--Roger Mayer Octavia?

Or the Tycho Octavia.

QuoteChorus

There are no effects circuits for chorus that don't involve ICs. It may be possible to build these from discretes, but no effects ever did. Possibly you could do something with two or more tape decks. Nothing in a stomp box.

QuoteCompressor

I don't know of any pedal format ones that have no ICs. There are studio tube style things, no pedals that I know of.

QuoteBass booster

Vox Treble/Bass Booster, EH Hog's Foot

QuoteSustainer

See compressor, above.

QuoteAttack/Decay and/or Auto-wah / envelope follower

These aren't the same thing, you know.
There was a Popular Electronics article on a discrete attack delay in the late 60's. Don't know of any commercial article.

QuoteFlanger

No flangers without either BBD ICs or two tape recorders in a studio.

QuotePhase shifter

Univibe or RT18.

QuoteEcho (not tape loop-based)

speaker and microphone in a BIG room, or a plate echo. Not exactly pedals.

Just out of curiousity - can you reliably hear when sound has been through an IC as opposed to all discretes? Or just don't like ICs on general principles?

I forgot one thing  - most of the early effects that were more complicated than fuzzes used gain circuits composed of two or three DC-coupled transistors that they used as gain blocks just like opamps. Does that count as an IC? Same kind of operation, high gain feedback amplifier.

Quote from: rch427 on October 06, 2005, 10:42:45 PMThe *minimum* for a decent-sounding effect--even used--is way more than the components cost to build, say, a replica of an early fuzz box.  Especially considering I'm not putting each one in its own enclosure.

So, I trust we can bury the cost issue and the "you don't know what things sound like" issue, OK?

Sigh. I mentioned nothing about the cost of parts. Using part costs as your metric for the value of an effect is literial thinking. I talked about your time and how much that is worth. If your time is worth little to nothing to you then in some cases go right ahead and DIY.

As for your other statements, well that says alot about your understanding. I already suggested a course of action so I do not need to comment.

Quote from: rch427 on October 06, 2005, 10:42:45 PMNow: how 'bout back to the original question--which of the effects on my shopping list were never made back in the discrete circuit days?  What work-arounds are possible?  Any answers to these sorts of questions is greatly appreciated.

From your list above I see right off the bat most delay based effects like flangers and echos use ICs be it analog or digital. Can you do it with discreets ? Yes but you will have to deal with thousands of parts just to emulate a single IC let alone any other ICs need (companders, timers, etc.) and the rest of the connective circuitry. Wouldn't is suck if you built a delay out of discreet parts only to find out it doesn't sound that special compared to a ICs or store bought unit or worse yet that it doesn't work ? Try debugging that baby (see "value of your time" reference above). Hmm...maybe there is a reason for ICs ? Nah.

Andrew

You do need to get over the dislike of ICs. I was the same, until I built an orange squeezer. That one converted me. Such a sweet compressor. ICs are your friend. The Maestro Ringmod for example is awesome because it uses an IC rather than a passive ring of diodes.
I gotta agree with my Tone God re: cost. I'd put at least a $50 per hour value on my time, assembly, debugging, painting etc sure start to add up then.

compressor/sustainer with no ICs??

Try the Roland Sustain or the SupaSustain...same thing.
Uses optos, but no ICs.

I really liked the original Roland Sustain.

Without an OTA IC, the only ways are opto or FET.

staysustained
tone

Quote from: octafish on October 06, 2005, 11:57:21 PM
I gotta agree with my Tone God re: cost. I'd put at least a $50 per hour value on my time, assembly, debugging, painting etc sure start to add up then.

Not to mention aggravation and frustration, which can drain you even after you stop working on the project.  With something as big as what you're proposing you can count on A LOT of time on debugging and general existential angst as you start to rethink whether it might have been better just to work overtime and buy the damn things instead.

I'm not trying to discourage you, but there are a lot of factors to take into consideration beyond $.02 resistors and $.11 capacitors.

Thanks, RG for all of the good advice.  

Maybe I didn't make it clear but, since I'm most interested in the *sound* produced in the mid-to-late '60s, I won't care as much about something not being possible to make, if it wasn't even being used back then.  

Yes, I know that A/D/S/R isn't the same as an auto wah, but I don't know which might've been used back then.  I'm also thinking of making the Jawari, so I can approximate a sitar (yes, I realize that's not "authentic").  I think it's like an attack/decay circuit with clipping, and I know it's all discrete.  

I don't have that much knowledge about the specifics of effects development.  I know some of the more obvious stuff, like some of Hendrix' gear, but I don't know, for example, who invented the first solid-state compressor, or when.  That subject is interesting to me, but I've never seen a book on the history of effects, that would explain it to me.  Does such a book exist?  

As for chips--I just don't like 'em.  They have their place in utilitarian things, but I they don't fit into my aesthetic.  I can *sometimes* tell the difference in sound between discrete and chip, although I've been fooled more than a few times.  Regardless, I don't like their rather stupid, anonymous appearance or their inscrutible function.  They're no more romantic than a new vacuum cleaner.  If I am happy to accept the limitations of using cheap, 40 year-old guitars and amps, why would I want to throw ICs into the mix?

Regarding multiple transistors used for gain blocks--is it really that much more convenient/economial to use an op-amp to replace just 3 or 4 transistors?  I'm willing to accept an old transistor's limitations and a certain amount of extra trouble and even expense (although I doubt it'll be that much more), for going with the transistors.

How 'bout everyone stop trying to sell me on chips, OK?  I think I made it clear that I don't want to use them.  I'm well aware that any new Japanese car can blow the doors off my '63 Dart GT, and any new Japanese scooter can beat my '65 Ducati.  Any new, Korean-made guitar is probably a "better" guitar than my 40-year-old Masonite Danelectros.  Any new high-end computer synth is "better" than any old Moog that has to be retuned every time you go to use it.  So what?  Not everything about vehicles or traveling or guitars or synths or anything else has to be reduced to cold facts about convenience or performance.  I want it old-fashioned, and I'm happy with that situation.  I can't get something exactly like what I asked for without resorting to using chips?  I can live without it.

Oh--and I actually *like* doing small electronic projects (or 15 of 'em in a row), so I'm not interested in factoring in the time I'll spend doing it.  It's a hobby, not a job that I expect $50 an hour from!  As for my patience--I think I mentioned that I just recapped an entire flippin' combo organ.  If I can desolder 292 caps and replace them, as well as doing countless other repairs on that one project--I think I'm up to this new project, thanks.

I wonder what an all germanium flanger sounds like?    Don't forget the carbon comp resistors and use nothing but sprague and mallory caps.

do it with no solid states.

jk

look at the second "project forum" - the discrete opamp replacer.  That should make lotsa stuff (orange squeezer) slightly more possible...

...

Thanks, RG for all of the good advice.

I don't have that much knowledge about the specifics of effects development.  I know some of the more obvious stuff, like some of Hendrix' gear, but I don't know, for example, who invented the first solid-state compressor, or when.  That subject is interesting to me, but I've never seen a book on the history of effects, that would explain it to me.  Does such a book exist?   

*****************Yes, http://www.smallbearelec.com/Search.bok?category=Books+And+Publications

Quote from: SonicVI on October 07, 2005, 01:02:41 AM
I wonder what an all germanium flanger sounds like?    Don't forget the carbon comp resistors and use nothing but sprague and mallory caps.

imagine a germanium + carbon comp compander.  :D it's there to keep the noise floor down.

if you want to consider the effects of that era, you're probably looking at various fuzzboxes, wahs, the univibe, and tape delays. that's about all of the pedals i can think of for the 60's... not a very wide selection.

please, PLEASE consider ICs. you can have so much more fun when you work with them. if you have some notion that discrete transistors sound "warmer" and that ICs sound "lifeless" then you seriously need to do some A/B testing. see if you're hearing it, or you're hearing an advertisement.

just some thoughts

Do you have any idea when you'd be starting/finishing this project?

I can't wait to see your results.

GO FOR IT!

Fp

rch427`s idea is absolutely cool,
and in a pure DIY spirit!

>>"I wonder what an all germanium flanger sounds like?"<<   

:icon_rolleyes: I get it; I get it.  There are some effects that are difficult to make with discrete circuits.  That's why I'm asking for info here.  I'm *not* asking for people to tell me what I *should want*.

>>"Don't forget the carbon comp resistors and use nothing but sprague and mallory caps."<<

I'll use carbon comps where they'll make a difference (in circuits where noise isn't an issue); otherwise, metal film.  And if I can justify Sprague and Mallory caps for a specific project, I'll be happy to use 'em.  Yes, I know you were being facetious.

Quotelook at the second "project forum" - the discrete opamp replacer.  That should make lotsa stuff (orange squeezer) slightly more possible...

Thanks!  What's such a big deal about using 3 transistors, a diode, a cap and 6 resistors instead of an op-amp?  Making that would take very little time, and only cost a few bucks.  And to all the nay-sayers: note where the author of that post wrote "It (the discrete circuit) overloads more gracefully than IC opamps"?  I'm not the only one who prefers the sound of discrete circuits.  It looks like quite a few folks in that thread agree.

Thanks!  Looks like I'll want to get both of them.

Quote from: wampcat1 on October 07, 2005, 01:19:29 AM
Does such a book exist?   

*****************Yes, http://www.smallbearelec.com/Search.bok?category=Books+And+Publications

Quote from: octafish on October 06, 2005, 11:57:21 PM
I gotta agree with my Tone God re: cost. I'd put at least a $50 per hour value on my time, assembly, debugging, painting etc sure start to add up then.

I've heard it too many times before and I think it's just plain silly. If I'm willing to take time to learn building stompboxes and designing them, why the heck should I count pennies on how much I build. I'm into DIY from my free time, so this time can't be evaluated as money. It can be evaluated as enjoyment.

I am very much like you, rch427. I hate anything digital between me and the guitar speaker. Op-amps are OK as long as they're out of my visual range. They just look so dang digital. Tubes are the best because you can actually "see" it working, all the innards and stuff, plus, it sounds sweet. Actually I dislike all the modern appliances and gadgets too, it all gets so tiny. Is it normal to mount the lifeworks of 30 bands in one TINY USB mp3-player? No. But I DO use the internet and a mobile phone because otherwise I'd be cut off from the rest of the world. And that's bad. Oh you'll HAVE to see my favourite film "Office Space", there's a scene where they beat up a copying machine on a meadow. Ahh I feel warm inside every time I watch that.
Sorry, getting a "little" offtopic here. Needed a vent anyway...

Quote from: SonicVI on October 07, 2005, 01:02:41 AM
I wonder what an all germanium flanger sounds like?    Don't forget the carbon comp resistors and use nothing but sprague and mallory caps.

That's just plain mean. You can have fun on this forum but not on your own forummates.

----------
Jimbo

Quote from: trjones1 on October 07, 2005, 12:52:24 AM

Not to mention aggravation and frustration, which can drain you even after you stop working on the project.  With something as big as what you're proposing you can count on A LOT of time on debugging and general existential angst as you start to rethink whether it might have been better just to work overtime and buy the damn things instead.

I think you should think about a new hobby if building pedals make you feel like that.

Well yes, I agree, sometimes it is frustrating to find out that you just had the IC in backwards after 3 hours of debugging, but it's not a thing to make a generalisation out of.

-------------
Jimbo

interesting thread. i'm curious to see where this project would go. i think i understand the rationale behind it. i'm guessing that part of the enjoyment of these effects will be knowing that they were hand made using components (for the most part) identical to the effects used in the era of the artists you mentioned. i think there might be a misundestanding here that your displeasure of ic's (digital or not) is equivalent to the "mojo" atribute often associated with boutique pedal hucksters. if i wanted to put together a replica of the kittyhawk because i wanted to tap into the experience of flying in that machine, i would not use aluminum or nylon. same thing, no?

  Here's a suggestion to 'compromise' your discrete 'particularity'...
  No IC"s *in signal path'...
  using a chip to drive an LED or other non signal path components opens up compressor, Vibe, and certainly others, if you hide the chip and can't actually 'hear' the 'chippiness' of it, maybe you can easily overlook that it's not an IC in your sound.
  There are nice chips though, and they certainly 'open doors' that you indicated you want opened...
 

rch427,

I am not going to praise IC's. Why? Simply because you don't want to. There are a lot of deviating longings and beggings going around. that's what makes a DIY community I guess?
I do have sympathy for your project. I just want to exchange my thoughts.

QuoteMaybe I didn't make it clear but, since I'm most interested in the *sound* produced in the mid-to-late '60s, I won't care as much about something not being possible to make, if it wasn't even being used back then.

QuoteThanks!  What's such a big deal about using 3 transistors, a diode, a cap and 6 resistors instead of an op-amp?  Making that would take very little time, and only cost a few bucks.  And to all the nay-sayers: note where the author of that post wrote "It (the discrete circuit) overloads more gracefully than IC opamps"?

First this is a circuit designed a half a year ago... not 60ties. They would never have thought about making this then.
Secondly it's all modern solid state silicon trannies...
Thirdly, It won't work in all circuits, mostly in distortion devices. And they are the simplest of things.

The Germanium love is widely spread, but only when speaking of simple non-linear circuits, where it's character can triumph. Silicon was allready wide-spread in the sixties/seventies you know. Most discrete non-distortion wonders have silicon (univibe,compressors). A lot of devices used silicon amplification (transistor) along with germanium diodes (clipping, radio recieving).

As long as you accept the limitations and inconsistencies, it's OK. But you will not be able to make delay, flangers and chorusses. Vibrato and Phasers on the other hand shouldn't be a problem, ranging from the Univibe to newly discrete designed perhaps?
Compressors are also very easy without IC's. Actually all the "doable" stuff relies on LED's or bulbs, FET's or LDR's, whether its phaser or compression.
"Real" delay, resulting in reverb, chorus and flanger is impossible without thousands of parts as allready said. Even if you have time, you simply won't get it in the box.

Quote from: Steben on October 07, 2005, 10:02:40 AM

As long as you accept the limitations and inconsistencies, it's OK. But you will not be able to make delay, flangers and chorusses. Vibrato and Phasers on the other hand shouldn't be a problem, ranging from the Univibe to newly discrete designed perhaps?
Compressors are also very easy without IC's. Actually all the "doable" stuff relies on LED's or bulbs, FET's or LDR's, whether its phaser or compression.
"Real" delay, resulting in reverb, chorus and flanger is impossible without thousands of parts as allready said. Even if you have time, you simply won't get it in the box.

First, he isn't putting these into a box. He said in one of the first posts he was going to put them into some kind of rack/table/all-in-one enclosure. Doesn't matter how big it is (and replacing chips with discrete is going to require some space).

I'm a bit disappointed. I'm a newb here, but the forum is usually a very friendly place. This guy is trying to do something different, and honestly, if he wants to spend the time to make an all discrete flanger/chorus, etc, then good for him. One thing I've often wondered about, after seeing the datasheets for some of these chips, is how cool it would be to manually making the equiv with cheap discretes. I actually had it on my list of future 'screw around' projects to try reproducing some chips with discretes just for the hell of it.

I'm a computer geek first, and as such, I read about all kinds of wacko projects, like the guy who built a replica of the Altair computer for fun, or the guys who shoehorn Linux onto every possible computing device (game consoles, PDAs, etc), or the nutjobs working on building their own BIOS. I remember one project where some guys were building their own graphics card chip. By all accounts, yes it is 'stupid' because they could just go get a real computer to work with for far less time and effort, instead of spending all of the time doing that, but maybe thats the fun of doing it, no reason other than 'because I can'?

Personally, if he manages to build some of these out of discrete's, I'd love to hear the results, and see the techniques used. I say go for it, and please let us hear/see the results!

Well, ok then. I said I had sympathy. It is going to be hard that's all, unless you stick to some limitations.
But WE cannot help him wiht that since we haven't got experience in rebuilding chips. If you want to rebuild delay chips, you should contact the manufacturers.

Quote from: Steben on October 07, 2005, 11:34:45 AM
Well, ok then. I said I had sympathy. It is going to be hard that's all, unless you stick to some limitations.
But WE cannot help him wiht that since we haven't got experience in rebuilding chips. If you want to rebuild delay chips, you should contact the manufacturers.

I guess I should apologize, I wasn't aiming at you. The first 'paragraph' was responding to what you said, but after that was a general statement. Don't want to seem like I was being a jerk and picking on you specifically.

Quote from: JimRayden on October 07, 2005, 07:58:11 AM
I think you should think about a new hobby if building pedals make you feel like that.

Well yes, I agree, sometimes it is frustrating to find out that you just had the IC in backwards after 3 hours of debugging, but it's not a thing to make a generalisation out of.

-------------
Jimbo

No, not every road to happiness is pure bliss at every point along the way.  In my admittedly limited experience I've had plenty of moments, and days, and weeks, of frustration, that doesn't mean in the end I'm not happy when I finally get it working.

Quote from: rch427 on October 07, 2005, 12:55:36 AM
How 'bout everyone stop trying to sell me on chips, OK?  I think I made it clear that I don't want to use them.  I'm well aware that any new Japanese car can blow the doors off my '63 Dart GT, and any new Japanese scooter can beat my '65 Ducati.  Any new, Korean-made guitar is probably a "better" guitar than my 40-year-old Masonite Danelectros.  Any new high-end computer synth is "better" than any old Moog that has to be retuned every time you go to use it.  So what?  Not everything about vehicles or traveling or guitars or synths or anything else has to be reduced to cold facts about convenience or performance.  I want it old-fashioned, and I'm happy with that situation.  I can't get something exactly like what I asked for without resorting to using chips?  I can live without it.

Oh--and I actually *like* doing small electronic projects (or 15 of 'em in a row), so I'm not interested in factoring in the time I'll spend doing it.  It's a hobby, not a job that I expect $50 an hour from!  As for my patience--I think I mentioned that I just recapped an entire flippin' combo organ.  If I can desolder 292 caps and replace them, as well as doing countless other repairs on that one project--I think I'm up to this new project, thanks.

Hey RCH427,

I have to throw my hat into the ring with you here--you're man after my own heart.  It's good to hear a kindred voice like yours.  I've emphasized on this forum a number of times that DIY should be about following your own vision and your own ears, and the technicalities and academics should be there only to serve those.  Unfortunately when you stand up and speak outside peoples' comfort zones, they can be a little hostile.  I never intend hostility, but often a contrary viewpoint is taken as such.  I say follow your sense of truth and beauty, and trust your ears.  They won't let you down.

BTW, I avoid op amps whenever I can.  And when I can't, I go for oldies like 741 and 1458, which sound fairly musical for guitar, but have a bad rap around here.

BTW II, it's possible to have an all-discreet signal path for things like echo/chorus/flanger, though the delayed signal would have to pass through BBD chips.  However, you'd be on your own to design/kludge those yourself.  It would also be possible to make a phase-shifter with little more than three transistors and four transformers. . . .

BTW III, how does that combo organ sound now?

Joe

rch427,

One thing I'd like to add, if you want to replicate an effect that has opamps in them, you could always grab the datasheet for the opamp, there is usually a schematic for the amp in the datasheet. I'm looking at the schem for an LM318 opamp, looks like there are ~40 transistors and a plethora of caps and resistors that make those up. Looks like a major pain to make, but possible, if you want to put that much effort into it. I'm fairly sure most other chip datasheets have the same thing.

Electronics is like buying a puppy.

You think at first it fills that cute little gap in your life, but you'l need a bed, blankets, collar, leash, carry case thing.  And once you've cleaned your 100th pee stain of the carpet, the dog starts to lose its appeal.  This is where you either call the pound, drive to another town and let the dog out of the car, or you make a commitment for the rest of the dogs life!

I thought at first it would be cheaper to buy my own, but it's just not as fun.  And sure, one purchase begats another.  At first I just needed and iron, then I needed a drill, now I need a dremel, I dont think the endless purchases is going to stop.  So I am making a commitment to effect pedals!

I promise I will not drive to another town and dump the contents of my tool box at the back of K-mart!

I applaud what you are doing and I want to see progress reports for every step of the way.

Viva committment!

Nicely put.

Making all those effects will be a lifetime commitment.  :P

Fp

totally with rch... here:
the topic doesn`t read: "EASY...", but rather: "EARLY..."

Personally, I use chips in just about everything I build these days - the more the merrier! - but I started out learning about simple transistor circuits and the first thing I ever 'designed' was a common emitter booster using the guidelines given in a textbook.  This grounding has stuck with me and served me well over the years, so even if there's an easier way to do what you want to it's worth pursuing your ideas as you'll learn a hell of a lot in the process…and if you end up using chips, at least you'll understand why they work!

Gez   Dolly

my site towards the bottom has alot of old school circuits.

as far as the compressor....i know that joe davisson had some interesting compressor type effect with diodes on his site and a discrete tube screamer as well.  

i wonder if you got into a situation where you had something that required an ic, if you could emulate what was going on in the chip with transistors.

anyway, check out my site below.....and your idea and future project sounds WAY cool.

This is kinda weird - dunno who I'm more uncomfortable with, the neo-luddites or the IC salesmen!   ;)

Sure, doing an all-discrete rackmount multi-F/X unit is gonna be a hard slog, and it's probably going to be noisy and fincky when completed,  but if the man wants to reproduce Mt. Rushmore using only hand tools, let him go for it, and more power to him!

It is a bit alarming to find out that we have so many passionate adherents to the "if it's old, it must be good!" philosophy, though - as somebody who grew up having to use that noisy, unstable "old-school" gear when it was still relatively new (late 60s, early 70s), I guess I'm just not very impressed with most of it. To each his own, I suppose, but give me reliable, consistent and quiet any day, even if it's got some (shock! horror!) digital stuff in it. As always, YMMV.  :icon_biggrin:

(http://www.diystompboxes.com/smfforum/Themes/classic/images/post/thumbdown.gif)...

For me, the 'chips vs discrete' question is a non-starter. I ask, "what do I want to do?" and then, see whatever is the simplest & best way. Personally, I'm biased (no pun intended!) toward chips, because there is usually less variation in a chip design. but, those old transistor designs sure were elegant, sometimes.. For personal DIY,  even if the circuit turns out to be sensitive to tranistor gain & leakage, why, you can swap away & maybe come up with one that is better than any other in the world. That's the bright side of making single boxes.
If you want to make a bunch of boxes, all the same, then you are goig to have to put some effort into designing so that the component variation is alowed for. I can guarantee this, though.. discrete design leads to you learning more electronics (whether you want to or not).

I think rch explained it pretty clearly.  He's doing this for the sake of aesthetic value.  Most of you are building stompboxes because you like making music--which is very strongly measured by its aesthetic value--so you should be able to relate.

He's taking on an ambitious project, and when he's done he will hopefully have a bunch of pedals that not only give him the sound he wants, but will also make him feel like he's back in the era and he will be pleased with what's under the hood.  How many people rebuilt a '68 Camaro thinking it's going to outperform a modern BMW?  It's just a sweet car.   Another way to look at it (just for perspective), when people training for sports, some coaches give them a handicap so that they will be forced to make other muscle groups stronger, or improve performance in a different area.  Likewise, building FX with only discrete components will make it like he's doing DIY FX building in the '60's when IC's were not readily available nor practical.  Furthermore, it will limit the number FX he can use to a certain variety and force him to a new realm of creativity musically.

So, now, rch.  I'm sorry I don't have any recommendations that are useful to your cause, but it looks like there have been some good recommendations by others in between the sales pitches for IC's.

Now I hope everybody will put aside opinions about IC's vs. discrete and just help this guy get going on this project.  You're not talking hime out of it, and there would be no value in it if you were successful putting ICs in his stompboxes.  How is it that such a simple question about discrete FX circuits turns into an argument?  It seems silly to me to argue about such things. Just my 2 cents.  I don't mean any personal offense to you all who may feel threatened--rather, this thread should be a relatively impersonal topic altogether.

here`s the schem of the very first envelope-follower ever:

(http://img.photobucket.com/albums/v437/latronax/ENVFOL_1.jpg)

(maybe also of interest for this here thread (http://www.diystompboxes.com/smfforum/index.php?topic=37679.0))

note: the left 41/2 tubes were not used.
the phono-input was utilized,
fed by a special (outboard) ECC83 filter stage (not to be shown/disclosed, here),
whose parameters where altered by a lightbulb hooked to the speaker-output;

As can be seen, the envelope follower had it`s own built-in tube-amp...

the build looked something like this:

(http://img.photobucket.com/albums/v437/latronax/env-pic2.jpg)

to all the criticasters: this combination of tube-envelope-follower
in combination with tube-filter (=FolloWah) happened years before Stevie Wonder
ever heard the word: mutron...

I've been very very quiet in the effects building in the last months (years...), but I had to add my 2 cents.

I also prefer discrete to IC based circuits for guitar, even if I also love new technology. So I know what you mean.

It's not a matter of saying that one is better than the other one, it's just a matter of feeling.

Go for it and have fun.

While I'm here... Just a suggestion of a circuit that you could try, a preamp/vibrato.

http://topnet.com.au/~hairbear/page.2.htm

It is not a vintage or known effect, but it is a circuit from these years. There are a lot more, but I just happened to see it on my computer while looking for some files.

Gilles

Here's a meta-thread from prodigy-pro.com about discrete opamps. Hopefully it's useful.

http://www.prodigy-pro.com/forum/viewtopic.php?t=281&sid=b265b3b980c874409d3b3f66b115d7ef (http://www.prodigy-pro.com/forum/viewtopic.php?t=281&sid=b265b3b980c874409d3b3f66b115d7ef)

Quote from: James V on October 09, 2005, 03:03:47 PM
Here's a meta-thread from prodigy-pro.com about discrete opamps. Hopefully it's useful.

http://www.prodigy-pro.com/forum/viewtopic.php?t=281&sid=b265b3b980c874409d3b3f66b115d7ef (http://www.prodigy-pro.com/forum/viewtopic.php?t=281&sid=b265b3b980c874409d3b3f66b115d7ef)

There are some nice links from that page, thanks!  I'll peruse some of this when I'm next having my legs waxed!

Gez      Dolly

Quote from: Transmogrifox on October 09, 2005, 02:19:39 AM
How is it that such a simple question about discrete FX circuits turns into an argument?  It seems silly to me to argue about such things.

Amen, my brother!

There's an objective world of facts about how electronics work, and then there's a subjective world of sound and music.  We DIYers must constantly straddle those two worlds.  If we don't we're essentially fighting a war of left hand against right hand, and we all lose.  There are countless rules governing electronics, but only one that governs taste: If it sounds good, it is good.

And furthermore: nobody here tries to talk Puretube out of his passion and conviction about tubes, although some folks around here (not me) would argue they don't sound any different than a handful of transistors or op amps.  The fact is, he's entitled to his aesthetic, and it's practically incidental that he's an electronics genius. (Besides, you have to love a guy who stretches the vocabulary limits of this forum by using a word like criticaster! :icon_wink:)

Joe

Is this DIYStompboxes or did I accidentally stumble on to a audiophool forum ? Whats all this "discrete/IC is better" crap ? Thats just silly talk.

The reasons I suggested ICs to the OP is not because I think they are better then discrete but instead in some cases the effects the OP was looking for could either:

1. Be made superior with ICs (boaster, buffer)

2. Be made significantly easier with ICs (phaser, chorus)

3. Not be made at all without ICs (delays, echoes, flanger)

The OP has the option of either removing the limitation of discrete only to get all the effects he requested or accept that they will not be able to do everything requested with only discretes. If he wants to make an all discrete BBD for example to learn or just for shits and giggles then I'm not going to stop them. I do idiotic things all the time just for kicks like restore a '71 Charger with the Super Bee package.

The OP's discrete/IC nerouses seem to be a subset of the "old is better then new" myth which we all know is fictatious but I feel the OP is not willing to take the time and effort to understand this and since this is not the time nor the place I will not follow through with the debunking process. Remember we are talking about a group (musicians) that like and/or have to live by various nerouses like accepting only certain types of woods, pickups, picks, strings, amps, tubes, etc. Trying to change those habits, which I'm sure we all carry, is extremely tough.

As for what side of the discrete/IC clan I'm on the answer is neither. I use what technology is the best for the job. That simple.

Andrew

"My one wish for you during your visit to Dollywood is that the wonder of the Great Smokey Mountains will touch your heart…and that you understand the inner workings of integrated operational amplifiers!"

QuoteIs this DIYStompboxes or did I accidentally stumble on to a audiophool forum ? Whats all this "discrete/IC is better" crap ? Thats just silly talk

this is the thread, where the OP (=Original Poster) asked for:

Quote...building a multiple-effects unit based entirely on trad, discrete circuits...

Quote...And in the interest of historical accuracy and tone (and because I hate chips), I want to do it all with discrete circuits; no op-amps or ICs.

Minimoogs actually do have IC's in them, the new Minimoog Voyager has even more than the original and sounds just as incredible. 

I don`t think that any serious contributor to rch`s goal
really wants to convince him to put these monsters:
http://www.triodeel.com/images/gaprk2w1.jpg (http://www.triodeel.com/images/gaprk2w1.jpg)
http://www.triodeel.com/images/gaprk2w2.jpg (http://www.triodeel.com/images/gaprk2w2.jpg)
into an existing circuit
as a replacement for each individual modern opamp, but...

I feel that this stuff is DIY. Do It Yourself doesn't give you a set of guidelines to work in. If you want to make boxes out of bear hide, and circuits out of bones and wood, have at it. DIY is a unique thing for each individual. I build a lot of my enclosures from scratch and from modified metal parts that were used for something totally different. About 75% of my components come out of junk VCRs, 8 Track Decks, Radios, etc. A lot of people think I'm insane to strip componets, when I can just buy new ones, or to make my own enclosures, when I could just by a Hammond box, but that's DIY to me. We have a lot of people on here that layout their own PC boards and populate them. That would drive ME insane, and I'd get no joy from that. That's DIY to them. Some people do amazing paint jobs and internal wiring, that's DIY to them. If all discretes is DIY to you, DO IT! Enjoy YOUR DIY! I place no value on my DIY time, because I enjoy myself. I do it for the thrill of making weird noises come out of a bunch of components and wire thrown together from a schematic that came off the Internet. What you're wanting to do, is a little like wanting to restore an old car. There's no money to be made. There's only money out of pocket, sweat and late nights scratching your head for thrill of the end result. Viva the end result!

Quote from: jmusser on October 10, 2005, 07:45:30 PM
I place no value on my DIY time, because I enjoy myself.

This deserves framing. Somebody was hanging it on me for buying a crap CD player for $10, but I pointed out that I would have a LOT more fun pulling it apart than watching a movie ($16) or reading a novel. Cheap thrills indeed!

Looking back at the original post. And the timeline. Keeping with the technology available I'd recommend, the following.

Fuzz, meh too many to pick from a nice PNP FuzzFace is probably the way to go though. For an earlier sound I'd recoment a second cabinet and an icepick or razor blades.  (build it)

Treble booster, RMaster, what else is there?  (build it)

Tremolo, ahhh tube amp forget the solid state stuff. (build it?)

(Vibrato seems to be missing here, and of course the answer is a Stratocaster)

Ring mod, yep a ring mondulator, is what you want, you can find a carrier lfo somewhere i'm sure. Not surer how this fits into the vintage sound you talking about though. (build it)

Octave generator - tychobrae has a better fuzz that the RM but the RM sounds better idf you replace the fuzz section with a FF. Soooo tychobrae if your a purist or home cook something if you want the best sound. (build it)

Overdriver, pffff turn up your guitar/amp louder. Okay, okay maybe some sort of full range boost. Modding the caps on the Rmaster should do it.

Chorus, you'll need a big room

Compressor, fuzz face, the lightbulb thing, (build it)

Parametric EQ, what the controls on your amp aren't enough? Nah not authentic.

Bass booster, hogs foot, but thats really just for a bass guitar. Oh I know heavier strings.

Sustainer, Les Paul. Pref with PAFs or P-90's

Attack/decay, record it backwards

Autowah, nah you'll have to use your feet.

Flanger, two reel to reel tape recorders running at the same speed with identical tapse then press one with your finger to retard it a little.

Phase shifter, hmmm I think the phase 45 sounds the nicest but its got a chip. No opinion on this one.

Echo (not tape based) who you kidding?

Noise gate, for an authentic vintage sound you probably want a hiss enhancer.

Spring reverb tank, ummm a spring reverb tank? Thats mechanical look for old combo organs etc they sometimes have pretty decent tanks in them.

Seroisly most people in the time period you are looking at didn't use any effects that didn't come in their amp. I still think you should lighten up on the ICphobia but thats not what you want to hear. I think some things are easily done look for the (build it)s. But somethings just don't seem justified. ie I can't imagine too many people used a passive ring mod w/ their guitar in the sixties, but all stompbox versions are IC based. Unless someone can correct me?

QuoteEcho (not tape based) who you kidding?

Once I did a thumbnail design for a tube based digital delay.

Lemme see...

it takes one duotriode per flipflop, 16 flops per word, and, say, 16K words for a reasonable delay. That's 16*16*1024 = 262144 duotriodes, not counting glue logic.

Assume we could do the glue for 10% of the memory array, so we have, in rough numbers, 288,000 duotriodes. That's 6.3*0.3 = 1.89W of heater power per triode, and assuming B+ of 250V and 1ma of plate current, 0.25W of active current per flop, so the power is 288,000*(1.89+0.25) = 616.3kWatt. Power supply efficiency is probably less than 80%, but let's be generous, so AC power input to the machine is 770kW.

If you can air condition for a net efficiency of 5, you'd spend 154kW to keep it cool, and we're up to 924kW, or just a hair under a megawatt.

And we haven't even touched on the issue of roadies to carry and set it up. 

Quote from: R.G. on October 12, 2005, 11:43:50 PM

QuoteEcho (not tape based) who you kidding?

Once I did a thumbnail design for a tube based digital delay.

Lemme see...

it takes one duotriode per flipflop, 16 flops per word, and, say, 16K words for a reasonable delay. That's 16*16*1024 = 262144 duotriodes, not counting glue logic.

Assume we could do the glue for 10% of the memory array, so we have, in rough numbers, 288,000 duotriodes. That's 6.3*0.3 = 1.89W of heater power per triode, and assuming B+ of 250V and 1ma of plate current, 0.25W of active current per flop, so the power is 288,000*(1.89+0.25) = 616.3kWatt. Power supply efficiency is probably less than 80%, but let's be generous, so AC power input to the machine is 770kW.

If you can air condition for a net efficiency of 5, you'd spend 154kW to keep it cool, and we're up to 924kW, or just a hair under a megawatt.

And we haven't even touched on the issue of roadies to carry and set it up. 

schem plz





;D


couldn't resist...

Maybe a phaser with 12 to 24 shift stages (can be done I guess) can emulate flanging. If you have more stages, maybe chorussing. You should damp the sweep range then (I mean not from 0 to 2160 degrees, but 1080 to 2160 degrees). You dont need an opamp ic for phasing. A Phase45 is feasable with a couple of trannies.

And check out the "Phozer" at www.runoffgroove.com. It has a nice simple LFO in it to use even with "real" phasers.

R.G., if you want an audio selay using technology pre BBD, one possibility is the mercury delay line (there was quite a few yards of this in a 1950s radar set I saw a few years ago, it was used to subtract ground clutter from the next sweep).
Or, my favorite, the williamson cathode ray tube memory!
third last pic on this page: http://www.ii.uib.no/~wagner/OtherTopicsdir/EarlyDays.htm

Then again, there is the garden hose http://www.uaudio.com/webzine/2005/august/content/content4.html

you guys are seeming to forget about oil can delays.  or telrays...

www.telray.com
morley had some as well.
and there are people who are making their own oil can delays ....

http://www.geocities.com/tel_ray/EDLschem.html
http://www.geocities.com/tel_ray/adnechoschem.html

nothing is impossible.... and it's totally reasonable with enough know how to make a tape based delay.  ;)

Quote from: R.G. on October 12, 2005, 11:43:50 PM

QuoteEcho (not tape based) who you kidding?

Once I did a thumbnail design for a tube based digital delay.

Lemme see...

it takes one duotriode per flipflop, 16 flops per word, and, say, 16K words for a reasonable delay. That's 16*16*1024 = 262144 duotriodes, not counting glue logic.

Assume we could do the glue for 10% of the memory array, so we have, in rough numbers, 288,000 duotriodes. That's 6.3*0.3 = 1.89W of heater power per triode, and assuming B+ of 250V and 1ma of plate current, 0.25W of active current per flop, so the power is 288,000*(1.89+0.25) = 616.3kWatt. Power supply efficiency is probably less than 80%, but let's be generous, so AC power input to the machine is 770kW.

If you can air condition for a net efficiency of 5, you'd spend 154kW to keep it cool, and we're up to 924kW, or just a hair under a megawatt.

And we haven't even touched on the issue of roadies to carry and set it up. 

Hmm, that sounds a lot like a tube based computer with more memory than they ever had back in the day :icon_biggrin:

By the way, on that scale you would also encounter the problems our grandfathers had with the first computers. Tubes break :icon_biggrin:. On a scale like that you could be pretty sure a tube would blow every few seconds or so :icon_neutral:

QuoteTubes break. On a scale like that you could be pretty sure a tube would blow every few seconds or so

Yeah, I thought about doing a quick calculation of the failure rate but decided against it because I thought it probably isn't outrageous enough to match the number of tubes and power numbers. Lemme see if I can do that...

If you power cycle it too much, a small signal duotriode tube will last, on average about 50K to 100K power on hours (measured life data in logic use, Annals of the History of Computers special issue on SAGE). So with 288K tubes, a tube will fail, on average, every 50Khr/288Ktubes = 0.1736 hours, or about about every ten minutes. That's moderately outrageous, but not hugely so.

However, if you use four more tubes per word to do an error correction code, you'll have to have two failures in the same word to get an audible failure. I'd have to get out the statistics textbooks to get the numbers right, but since you have 8K words of 20 bits to get failures in and you have to have two failures in the same word to get an audible failure, the time between uncorrectable audible failures goes up by several orders of magnitude. Of course, that's just putting maintenance off and you have to replace all the single failure tubes when you get a double failure, but it gives you much longer run times, up in to days without a hard failure.

well, Telray became Morley...
Lubow (of Telray fame), however wasn`t the first "mechanical BBD" user...

you`d have to go  back to 1927... (http://www.pat2pdf.org/patents/pat1851090.pdf)

In the late sisties, my dream was to get a tape Echolette, or an Echochord to go with my no-effect 100W tube amp.

I also wanted to build a Fuzz or Preamp (not sure), based on a circuit I saw in one of the electronics mags that was popular at that time. The format was smaller than todays's mags and easier to take with you. Funny how things change... Computers gets smaller, mags get larger!!!

Anyway, that article was based on a miniature triode. I wished I still had this article. 1969?

Then came Craig Anderton. That's when I really started to build something.

My first home sound system... a mono 10 W tube amp I built myself.

I can't believe I use ucontrollers these days to control effects with 4053s and FETs, etc... And I like Boss effects with their FET switching circuits.

I also find it funny that people say that older technology is no good anymore... and that the same people still only use True Bypass.

Btw, this is just a funny thing I noticed, not a rant...  ;D

Gilles

soon come: The Tube-Switcher
:icon_wink:


(no joke!)

What would happen if someone built a tube version 4053/4066. True tube bypass. Is it truely all tube ? Is it true bypass ? Will the tube(s) make up for the non-true bypass-ness of it ? That would screw the heads of many a guitarists...not like that is saying much. ;)

Andrew

Yeah, but what does tube switching glitch sound like?  Does it have rounder corners??  :icon_razz:

sur-name: "Smooth Operator"...

I like it.  :icon_mrgreen:

What I had in mind (and began to use) was a standard preamp (Fet/Mosfet/transistor) that would be switchable.

A switchable tube preamp would be... well... heu... smooth!

Very old fashioned.

As Peter Cornish said: " a friendishly clever pre amp that has the same characteristics as the input of a tube amp " etc...

Gilles

Sorry about the long delay in getting back to this topic; it's been a hectic week. 

Thanks to everyone for continuing to offer suggestions, and especially to those of you who were so enthusiastic with your encouragement.  To catch up with a couple of questions:

Marc-- yes, part of my pleasure from this contraption will be in feeling the connection with the way things were done in the past. 

Steben-- yes, I know the Jawari was designed just a couple of years ago, and I think I mentioned that I realized it wasn't a truly "vintage" effect.  But I can't justify the price of a Jerry Jones sitar, and I can't find an old Danelectro baby sitar in my price range.  The Jawari IS, however, 100% discrete and entirely within the technology (and aesthetic) of the target era.

Joe Kramer--the combo organ now sounds pretty good, but I don't think any of my guitar amps are really suiting it.  I'm going to have to look into a dedicated amp for it.  But at least it stays in tune, and it doesn't smoke anymore!

PenPen-- thanks for the advice about reverse-engineering op-amps; I may end up doing that with one or more of the more complex circuits.

Lovekraft0-- I don't necessarily subscribe to the "if it's old, it must be good!" philosophy.  I subscribe to the "if it's old, *I'll probably like it*" philosophy.

Octafish-- yeah, I know that most of the guitarists in the mid-late '60s didn't have much to work with, but it wasn't for lack of wanting new gadgetry.  Ever hear The United States of America's record from 1968?  The ring modulator work on it is brilliant.  And many of the early prog guitarists used anything they could get their hands on.  Brian Wilson was a serious gearhead, and would've used all of these gadgets and more.  I just want to play around in an alternate history, using the same technology in new ways.

Anyway, after poring over hundreds of schematics, I think I’ve finally got my all-in-one effect unit pared down to a “short” list:

Overdrive: Sola Sound Tone Bender Mk. II

Attack/decay: this one http://members.shaw.ca/roma/attack.html (http://members.shaw.ca/roma/attack.html)

Bass booster: Electro-Harmonix Hog’s Foot (or Mole)

Treble booster: Electro-Harmonix Screaming Bird

Passive ring modulator: 2-transformer passive-type.  What would happen if I made a simple, tunable tone generator to provide the second input, and tuned it to the song's fundamental?

Pseudo ring-modulator: J D Sleep’s modification of the Dan Armstrong Green Ringer

Octave generator: on Octafish's recommendation, the modded Roger Meyer

Sustain: this modified Roland unit http://members.shaw.ca/roma/sustain.html (http://members.shaw.ca/roma/sustain.html)

Parametric EQ: this one http://www.mitedu.freeserve.co.uk/Circuits/Audio/t-ctrl.htm (http://www.mitedu.freeserve.co.uk/Circuits/Audio/t-ctrl.htm) (the "tone" controls on my amps are a joke)

Tremolo: either the Electronics Australia one or the "Twin-T Oscillator" here: http://members.shaw.ca/roma/vibrato.html (http://members.shaw.ca/roma/vibrato.html)

Reverb: Accutronics spring reverb with discrete transducers circuit.  I've got a spare tank, ready to go.

Headphone amp: having a heck of a time finding a discrete circuit for one of these!  Any leads?

Noise gate: in lieu of being able to find an actual guitar effect that does this with a discrete circuit, I’m thinking of building this audio circuit from Philips, from the late-‘60s http://freespace.virgin.net/ljmayes.mal/comp/philips.htm (http://freespace.virgin.net/ljmayes.mal/comp/philips.htm) .  If I'm feeling *really* ambitious.

Auto-wah: I’m wondering about combining an optoelectronic wah with a line-signal-driven lamp.  My theory is this: instead of the intensity of the light falling on the photocell being varied by the foot pedal, the audio signal itself would vary the light intensity relative to the signal's strength, thus causing the “wah” effect to fluctuate.  Has anyone else done this already?  Any reason why it couldn’t work?

I just might take Steben's suggestion and make that "Phozer" too!

Echo: I've decided to omit this project, as I just bought an old Univox tape echo unit that'll work well enough.

I wonder if it would be fun to put a pot at the power-in for some of these effects, to be able to simulate the "dying battery effect".  Any thoughts?

I'd kind of like to make a 1 or 2 tube overdrive unit, but haven't been able to find a schematic.

So, I've ended up with 12 or so circuits; all of which will be given true bypass switches.  Here's what I have in mind for the enclosure: I have a bunch of old Zero-Haliburton aluminum cases.  I think I'll take one that's about 15" x 20" by about 9" deep, and turn it into the enclosure for the effects.  Eventually, I'll make some legs for it, so I can have it straddling my amp, and be able to operate it with my hands, while sitting on my stool and playing. 

Here's what it looks like now: (http://img.photobucket.com/albums/v332/pygar/case.jpg)

...and here's what I have in mind for the larger half: (http://img.photobucket.com/albums/v332/pygar/case2.jpg)

I'll make an inner wooden frame that will horizontally divide the lower (larger) part of the case into 3 bays.  The bay configuration will hold the effects as modules, and will allow flexibility and expansion.  Some of the more complex effects will take up two module-widths, but I think I can keep most of them down to one. 

Each effect will be built onto standard 1/8" thick tagboard or perfboard, with two pieces meeting perpendicularly, and attached to two adjascent sides of a piece of 1/2" birch ply.  Affixed to the top of the ply will be a sheet of 14-ga aluminum, which will be the effect's face-plate.  There's a sketch here, to give you an idea:(http://img.photobucket.com/albums/v332/pygar/module.jpg)

Bear in mind that you're looking at the underside of one module.  And pay no attention to the "circuit"; it's nonsense--just there to give a sense of scale and construction.

Built into the bottom of the main enclosure will be that Accutronics spring reverb tank, a 120vAC-to-9vDC power supply, a small DC fan (probably a computer fan), and a grounding point. 

So--there you have it: a self-contained effects unit that's flexible and easily modifiable, that I can put the lid on and securely latch, for transport and protection.  A pretty ambitious project, but not any more difficult than lot of other projects I've undertaken.  I should be able to complete one module every few weeks, so as to have it all done in under a year. 

I'd be curious to hear anyone's opinion, so long as it doesn't involve me chucking this in for a new, digital effects box! 

rch427,

You mention "overdrive" with the Tone Bender MkII. The MkII is the most aggressive vintage fuzz known even in the tonebender arsenal. Just picking maybe I know, but "Fuzz" is the right word here. I was afraid you might be hoping to get another sound?

For a gentle overdrive, try tubes indeed or try the fameous !discrete! soft compression opamp of Joe in a tube screamer circuit.

And besides: "digital" is a way more easy enemy here than "IC".  ;D Except for the CMOS logic chips, that are "abused" in analog operation. That is a nice thing to do also.  :P

And for my quote tag line: You are allowed to break rules!

For a book on the history of effects units try "Stompbox, a history of guitar fuzzes, flangers, phasers, echoes& wahs" by Art Thompson published by Millar Freeman Books. Pub price $24.95. This is available in some UK clearance bookshops for between £5 and £7. They have it in Chorley and I bought mine from Liverpool. This book is excellent with interviews with the makers and designers of all your favourite circuits (well some of mine anyway!)

Are you planning on running all the effects in the case ? It sounds like you are. In that case you might want to add some shielding around each box. With all that exposed circuitry you will have noise issues. Also don't forget your power supply. You will probably want to isolate all the power outputs to reduce various issues. Make sure the power supply is spec'd to deliver everything you need for each effect.

Andrew

Quote from: rch427 on October 14, 2005, 03:38:31 AM
....Headphone amp: having a heck of a time finding a discrete circuit for one of these!  Any leads?

This could be a start

http://www.redcircuits.com/Page30.htm

http://www.redcircuits.com/Page31.htm


Gilles

i see some laurier circuits in there... 

careful. they have a nasty reputation...

Quote from: Connoisseur of Distortion on October 15, 2005, 02:12:17 AM
i see some laurier circuits in there... 

  ??? ??? ??? where :icon_question:

in rch`s long post on the page before.

Quote from: rch427 on October 14, 2005, 03:38:31 AM
Passive ring modulator: 2-transformer passive-type.  What would happen if I made a simple, tunable tone generator to provide the second input, and tuned it to the song's fundamental?

I expect an octave up, with a tremolo effect as the tone generator falls in and out of sync with the fundamental. And plenty of original signal leaking through, plus non-harmonic tones from the non-fundamental frequencies in the song. Go for it!! nice to see someone trying to realise a vision. Will be a long haul... good luck!!

Hi!

Nice project, hope you can get what you want.
I have some sugestions for pedals....
Try a simple Idiotwah (T.Escobedo) coupled with a simple transistor peak detector (LED+LDR thing).
Search for old electronic articles on the net. Mark Hammer has some...
Search for old sinth circuits.
Try the Harmonaphone for all transistor octave down. Try varying the frequency of the elecrtic motors
on your tape echo to get flanging and chorusing.
Good luck!

Pedro

i meant in the list he posted, not your links

Quote from: Paul Perry (Frostwave) on October 16, 2005, 08:03:51 AM

Quote from: rch427 on October 14, 2005, 03:38:31 AM
Passive ring modulator: 2-transformer passive-type.  What would happen if I made a simple, tunable tone generator to provide the second input, and tuned it to the song's fundamental?

I expect an octave up, with a tremolo effect as the tone generator falls in and out of sync with the fundamental. And plenty of original signal leaking through, plus non-harmonic tones from the non-fundamental frequencies in the song. Go for it!! nice to see someone trying to realise a vision. Will be a long haul... good luck!!

If it's a studio effects unit why not just use a single VCO output from a synth?

With a case like that and everything integrated, consider using SPST stomp switches and little relays to do the actual signal switching. The "brute force" way to do that would be with something like  a 25 conductor computer cable with DB-25 ends. DB-25s were used on teletypes so that should be OK with the old-tech thing. ;)

If you use connectors, you don't have to worry about the cable too much as it can be easily extended or replaced as needed. Using a couple wires for power and ground could give you up to 20 stompswitches. It's overkill, but it uses standard off-the-shelf cables you can get anywhere.

That approach gives you a small profile remote system.

Two transistor flipflops could be also be used along with momentary switches like Boss does. That way you could have a pushbutton on the suitcase to toggle effects too, but then the footswitch wouldn't have status lights on it. Hmmm...

I like the idea of modern components working in tandem with vintage ones. Modern stuff does the switching stuff really nicely and it's cleaner to switch with signal relays than lots of wire and mechanical switches.

If you're really onto "old school", this is required reading:
http://www.analog.com/library/analogDialogue/archives/philbrick/computing_amplifiers.html ;)

Download the whole thing and save it for later use. 75M :o

Steben -- I guess I was misinformed about the earliest Tone-Benders; from the reviews I read on Harmony-Central, I thought they were more of an overdrive effect than just waveform clipping.  OK, then it looks like I'll want to do a separate, clean overdrive unit.  What is "...the fameous !discrete! soft compression opamp of Joe in a tube screamer circuit"?  Who is Joe, and is this an op-amp circuit or discrete?

ASP -- Yeah, sorry, I must've missed that earlier mention of the auto-wah.  Thanks for pointing it out.

Col -- thanks for the tip; on your recommendation, I just picked it up at the local Borders Books.

Tone God -- How would you recommend dealing with shielding the units?  Copper sheets lining each module's compartment, grounded to the case, or what?  And how about shielding the power lines going to each effect?  Shielded cable (likewise grounded), or what?

Gilles -- thanks for the link to the headphone amp schematic!  The second (discrete) one is powered by 3vDC.  How would you recommend dealing with that, given that the other circuits are 9v? 

Commoisseur of Distortion -- your "Laurier Circuits" reference went right over my head.  What's the story with them?

Pedro Frietas -- thanks for the info about the Idiotwah--that looks like just what I need, so long as I can figure out the other part of the circuit (the peak detector).  I haven't been able to find anything about the Harmonaphone through Google, tho'.

SonicVI -- do you mean that I should attach the effects unit to my synth, or just build a separate, self-contained VCO?  Will a single VCO really do what a ring mod does? 

Peter Snowberg -- Thanks for the idea about using transistor logic gates for the switching.  And thanks for the link to that book on Amplifiers, Computing and Everything.  I now have my reading set for the next 10 years now.

Thanks again to everyone for the continuing good advice, and for the patience with my hare-brained scheme.  BTW--a friend of mine in the Netherlands is sending me a shoebox of germanium transistors he's been hoarding for years now.  Looks like I'll be spending some quality time with the transistor tester when they arrive.

-- Robert

Quote

Quotelook at the second "project forum" - the discrete opamp replacer.  That should make lotsa stuff (orange squeezer) slightly more possible...

Thanks!  What's such a big deal about using 3 transistors, a diode, a cap and 6 resistors instead of an op-amp?  Making that would take very little time, and only cost a few bucks.  And to all the nay-sayers: note where the author of that post wrote "It (the discrete circuit) overloads more gracefully than IC opamps"?  I'm not the only one who prefers the sound of discrete circuits.  It looks like quite a few folks in that thread agree.

I was referring to Joe Davisson's discrete soft-compression opamp. You already saw it  ;D
With this you can make a tube screamer - like overdrive very easy. It will probably sound more pleasant than a stock IC as overdrive ISN'T about hifi linearity... Remember all TS - pcb's use dual opamps, so you need a (simpler) design.

Quote from: rch427 on October 17, 2005, 11:35:26 PMTone God -- How would you recommend dealing with shielding the units?  Copper sheets lining each module's compartment, grounded to the case, or what?  And how about shielding the power lines going to each effect?  Shielded cable (likewise grounded), or what?

Copper would work. You could also use metal duct tape, not the cheap plastic stretch type of duct tape. The problem is the metal duct tape is aluminium which you can't solder to. The copper you would be able to solder too. Also some tape will not conduct through the glue backing so layering the edges of tape on top of each other will not guarantee a connection amongst the various strips of tape.

You can get around the problems by lining the effect case with tape length wise meaning the end of the tape comes out the top of the box. With the tape sticking out if top of the effect box you can wrap the tape around the top lip and attach your face plate thus making a connection to all of the tape through the face plate. Looking at your drawing the face plate will be metal which I assume will attach to a frame of some sort inside the carrying case. If you ground the frame the effect's faceplate attaches to you will ground the tape and shield the effect box. Make sure to test the tape/ground connection with your multimeter after each case is done.

If you will have any transformers in the system say for your power supply you might still want to build the power supply case out of steel. You can use thin sheet metal like that of a metal stud or duct work. Steel will keep EM noise (AC hum) out of the rest of the system. Ground the case of course.

As for power cable I wouldn't worry too much about using shield power lines. Power typically picks up little noise during it's travel. If you got the wire already then go ahead as there will be little consequence but otherwise I wouldn't bother. You still might want to look into a isolated power supply system though.

Hopes this helps.

Andrew

the laurier circuits are pretty famous for working sub-par or not at all. from what i understand, their vibrato is actually a tremelo, and people very frequently have difficulty getting the circuits to work. i was recently looking into vibrato circuits, as i am interested in trying to make a pseudo chorus using one...

Re: the discrete opamp tubescreamer. Try searching discrete compression tube reamer in the archive. The tube reamer is a runoffgroove circuit, and even if you don't find the full schem incorporating Joe's opamp, its pretty easy to sub it in. While not really necessary with the reamer, I'd recommend breadboarding with an actual IC to see if you like the general sound of the circuits before going and building a full discrete version, especially if you where to try to do an exact copy of an opamp rather than a simplified version like Joe's. You don't want to spend a whole bunch of time on a project to find you are dissatisfied with the sound of the actual circuit.

Re: The ring mods. You'll need some sort of pretty beefy booster to amplify your guitar signal for a passive ring mod, normally I'd recommend an opamp or a 386 amp but in your case once you get the headphone amp sorted maybe you could use that? BTW in my experience a simple booster like the LPB-1 didn't cut it.
      Also have a good look at the green ringer and the second half of the RM octavia, pretty similar huh? The green ringer IMHO isn't really very ringmoddish, Its sort of like splitting a signal and feeding it into both carrier and modulation inputs, (Actually thats ecaxtly what the Tychobrae does even to the point of incorporating a transformer).  Before building the RM I'd say build two or three fuzzes (your chosen tone bender, a more subtle fuzz face and something truely offensive, the univox square wave?) and the ringer, you'll find a bunch of RM like tones in those combinations.

Congrats on the tape echo.

edit: Are you going to build a patchbay for this? Seems to me you would want to vary your effect order quite a bit.

(http://img.photobucket.com/albums/v280/Snowberg/diy/diodecompressionreamer.gif)

:D

Connoisseur of Distortion, I agree with you that "some designs" are to used with care . I was affraid that Red Circuits were mistaken for one of those... ;)

I like discrete Red Circuits, an I wish he was doing more designs specially for guitar  ;D

rch427, I sent Red an email to know his feeling about using it on 9V, both because I don't have time to do it myself, and because he knows his circuits more than us...  We'll see.

Gilles

Quote from: rch427 on October 14, 2005, 03:38:31 AM
Sustain: this modified Roland unit http://members.shaw.ca/roma/sustain.html (http://members.shaw.ca/roma/sustain.html)

I build this a few years ago... the sustain is good (not infinite though) and the sound is sligtly distorted (not in a way that I liked). I added a transistor stage after it and I got huge distortion combined with the sustain: i did use that effect some time.

But the sustain alone didn't impressed me. Could have been my build anyway.

Luck

Miguel

I have a schematic for a tube screamer/tube bender style of overdrive that goes from ac 15 to marshall stack that operates with four trannies and '0' opamps if you are interested?

let me know

  Discrete OA 'socket matcher' [Opamp circuit 'plug'?]
  I built a discrete OA using stamp sized perf, and soldering solid core wire leads [like 1/2w resistor leads, straight down [about 1/4'' long to stick in an IC socket], I built the transistor OA circuit on the perf into a pattern matching an 8pin IC socket, then it could be plugged in where a single opamp would be.
  I decided this might make debugging easier because I could take the OA and place it where I know an IC opamp works. It Fired right up.
  IMExperiment, I used a DS-1 clone [the bulk of the method might not fit in a Boss box] and inserted the "D.OA in the circuit, and it provided certainly a different sound and somewhat less gain that the IC.

Quote from: Gilles C on October 19, 2005, 10:23:54 AM
Connoisseur of Distortion, I agree with you that "some designs" are to used with care . I was affraid that Red Circuits were mistaken for one of those... ;)

I like discrete Red Circuits, an I wish he was doing more designs specially for guitar  ;D

rch427, I sent Red an email to know his feeling about using it on 9V, both because I don't have time to do it myself, and because he knows his circuits more than us...  We'll see.

Gilles

Ok, the answer from Flavio (Red Circuits) about the 3V headphone amp is: "The main problem related to 9V operation of my Portable Headphone Amplifier is due to its Class A operation....the best solution could be to design a 9V Class B Headphone amp"

Sorry  :'(

The good news is that he also wrote: "I do not have a circuit of this kind at hand, but I could plan to design it in the next months. "

So the options would be to design one right now, or wait until he have time to come up with a new design.

Any takers?

Gilles

early trem:
http://www.pat2pdf.org/patents/pat3240859.pdf (http://www.pat2pdf.org/patents/pat3240859.pdf)