Thunderchief is a JFET emulation of the Marshall 100W Super Lead. Check it out!
Article and schematic: http://runoffgroove.com/thunderchief.html
Sound clip: http://runoffgroove.com/salvo.html#thunderchief
8) 8) 8) 8) 8)
As always... my hat is off to you guys! Fantastic work!
I've been playing with JFET pres in the Fender and 'Wreck territory for some time with results that my fried ears seem to like. You show this is equally effective for Marshalls too. I wonder how well it would work for a Dumble flavor (with said tone stack)?
Again, great job! 8)
Take care,
-Peter
Thanks, Peter.
Thanks to Doug Hammond and his Meteor for showing us how to do this. The quality of the distortion is so much better than a diode clipper. It's incredible. Thanks again, Doug.
We also played around with the SLO 100 and the 5150 amps. We settled on the Marshall Super Lead, due to the nostalgia factor. That and the amount of gain was rediculous!
Nice job, Gary and Brian!
I designed something last year that used a rotary switch to change between 3 different marshall amp voicings: jtm45, 1987, and 1959. It sounded good on the breadboard but seemed like such a PITA to build due to the switch, I haven't gotten up the enthusiasm to construct it. Anyway, I dumped the "PI" and jfet output stg in favor of Joe Davisson's Blackfire stage, and ran the NFB back to the 2nd preamp stg instead. I also tuned a separate feedback loop for ea voicing, with some bass resonance to pump up da bass appropriately and even out the response for ea setting.
I also tried an SLO, but it sounded just like Joe's Blackfire to me. Some day I want to try Ansil's Ecstacy ("Eggstacy") too. It looks pretty nice.
Peter- Aron did a JFET "*umble" design a couple years ago. He had a nice LC-sounding clip with his 335.
Doug
All I can say is hey :wink:
A great job, really!!!
nice job!!!!!!!!
peace,
- tom
amazing, guys. i may actually try and build this!
i looked on the site, but didn't see any kind of fair use/IP-type info. what are your requirements or thoughts or philosophy for using the circuits on runoff groove?
-ian
Crikey, you guys don't stand still, do you?
Any ideas for a circuit that uses 12AX7 valves voiced to sound just like a classic 1970s 2N3055 push-pull transistor output stage? [Runs from hail of abuse and flying beer cans :D ]
Words of Keith..."You are only as good as your last rythm".
I like hearing modern incarnations of SAM.007 !!!
Very Nice sound clip! Put a smile on My head.
It is a Runoff Deluxe Groove !!!
It sounds to be 'worth the count"!!!
Now you've done it!
Now I've gotta go buy more perf!!
Regards!!!
RDV!!!!
Quote from: Ge_WhizAny ideas for a circuit that uses 12AX7 valves voiced to sound just like a classic 1970s 2N3055 push-pull transistor output stage? [Runs from hail of abuse and flying beer cans :D ]
LOL! :lol:
Cool name, nice circuit, but you guys are killing me.
Keep up the great work. 8)
Wow... that has the sweet gainy-but-not-nasty sound :D amazing... Dang why can I not choose what to make? All the runoffgroove distortions sound great 8) I might just build them all.... :roll:
Thanks, all.
Doug, do you remember me asking about the SLO after you released the Meteor? We were playing with this stuff then. We didn't get it right until now. Thanks for teaching us how to do it. The PI is a little tricky.
I wonder if this is how Brian Mena does it?
BTW, everyone reading this that has not tried Doug's Meteor, do it now! You've never heard a distortion pedal sound so good.
Thanks for sharing this, really looks great.
Definately going to build this one. I'll make a PCB for everyone to make this build a lil easier :wink: Good job guys!
This is great. I'm probably gonna build it. Anyhow, does anyone have a perf layout for it? Thanks.
How do you expect us to follow your updates? I need more perf!!
Thanks again guys!
Quote from: GaryThanks, Peter.
Thanks to Doug Hammond and his Meteor for showing us how to do this. The quality of the distortion is so much better than a diode clipper. It's incredible. Thanks again, Doug.
You are right on the mark IMHO. JFET's do have an amp-like sound quality where diode clippers are buzzy/fuzzy sounding, the definition of solid state distortion in my book.
Great work guys and I agree that Doug's work has been extensive and inspiring.
Take care, Jered
Hey guys - great tone ... truely a wonderful pedal...
oh, and doug - speechless...
Hi Gary and Brian,
Your Thunderchief looks real good!
I would love to hear the sound clip but I can’t find it on your sound page. http://www.runoffgroove.com/salvo.html#thunderchief
A general question:
Have you tried doing a similar circuit using mosfets instead of the JFETs and limiting the gain to approx 100 like the 12AX7, by adding some resistance to the .68uF source cap? I wonder how close they might sound.
I wonder if part of the secret to the sound is the maxed presence control.
Regards,
Will
Will,
The maxed presence control does make a difference.
Gary, any plans to introduce a perf layout for this baby?
Quote from: GaryThanks, all.
Doug, do you remember me asking about the SLO after you released the Meteor?
Yes. I remember that. This CS JFET approach can be applied to a lot of different circuits.
Quote from: Gary
BTW, everyone reading this that has not tried Doug's Meteor, do it now! You've never heard a distortion pedal sound so good.
Thanks. :D I have been using the meteor in my weekly gig and am very happy with it. It has exceeded my initial expectations by far, when in a live situation at stage volume. Makes my SS amp sound like a boutique... :D
Doug
Quote from: javacodyGary, any plans to introduce a perf layout for this baby?
I plan to draw one today, actually!
QuoteTry using different JFETs. J201s provide more gain than the actual amp had. It sounds great, but may be too hot for some. Try lower powered JFETs for a milder, more classic sound.
Any suggestions for this?
What parameter should I be looking at in a datasheet? How much gain does a 12ax7 have?
Awesome Brian! I don't know what I'd do without Runoff Groove. You guys keep me busy!
I would really like to know, once I have the thunderchief done, how to do something similar for the famous 60's Marshalls.
A (currently untested) perfboard layout has been added to the Thunderchief page: http://runoffgroove.com/thunderchief.html
As others have said - Runoff Grove keeps me busy.
Listen to the clip last night and the 14yo said - "Now that's the sound I'm looking for!"
I drew up a EXPRESS PC layout. Would like to have someone verify - please email if interested.
Thanks again-
BILL
What would 680nF be in uF?
Quote from: javacodyWhat would 680nF be in uF?
That would be .68uF
0.1uF = 100nF
0.01uF = 10nF
0.001uF = 1nF = 1000pF
We've decided to adopt the Euro notation style for new content at the 'Groove. It reduces the confusion (though not in this case!) and gets rid of the pesky zeros when labeling the layouts.
Javacody, that would be .68uF Arno, try 2N3819, 2N5457, 2SK30, or for more gain 2SK117, 2SK118, and 2SK184. MPF 102 fets will work but your not going to get the gain this pedal wants to sound really good.
Good luck, Jered
Arno, check this out from the DIY FAQ:
"What FETs can I substitute in the Mini-Booster and Shaka etc...? I can't find the J201....
From Jack Orman:
This is a recurring question eventhough the information was in the Mini-Booster article at AMZ From the article: "The NTE458 usually has more gain than the J201, and the 2N3686 can provide gain of 500. The 2N5457, MPF102, and 2N3819 will produce less gain. Other substitute transistors include 2N5484, 2SK43, 2SK68, 2SK117, 2SK118, 2SK121, 2SK163 and BF245."
Java,
This circuit is based on the '70 Super Lead schematic on www.schematicheaven.com The older amps are not very different. It should be easy to change things around and have a JTM45.
Thanks guys,
I figured I just divide nF by 1000 to get uF, here is a parts list I threw together:
Resistors:
68K
2 - 1M
2K7
470K
2 - 1K
2 - 4K7
470
220K
2 - 15K
100K
Capacitors:
2 - 0.68uF (680n)
3 - 0.0022uF (2.2n)
3 - 0.022uF (22n)
470p
2 - 0.1uF (100n)
100uF
Pots:
4 100k (trim)
1M Audio
100K Audio
JFET's:
4 J201's
Jacks:
1 Stereo
1 Mono
Switches:
1 DPDT or 3PDT
Does that look right to everyone?
Quote from: javacodyDoes that look right to everyone?
Looks like you got them all!
:!:
Would a 500K gain pot, effectively lower gain on this effect?
...try a 1 meg resistor, connected to lug 1 & lug3 of the 1M Pot
Adjust as necessary
Come to think of it- how come Marshall never did this themselves? Seems they went mostly the diode clipping route with their stompboxes, didn't they?
Kerry M
Quote from: bwanasonicCome to think of it- how come Marshall never did this themselves? Seems they went mostly the diode clipping route with their stompboxes, didn't they?
Kerry M
...and with their amps too ;)
Excuse the stupid questions, but what amp did you guys use to prototoype this pedal with, and how did you have it set?
Second stupid question: how come you guys don't post soundclips with amps and pedals? The convenience issue aside, how really is a pedal played through a simulator and/or preamp recorded direct supposed to give one an accurate idea how the box will sound in the "real" world?
Please no offense I just don't understand, I just have yet to hear a pedal recorded direct that sounds even remotely close to when it's cranked through an amp and the tubes are hot and the speaker is pushing air...
thanks for your thoughts
I don't know about what Marshall might have tried over the years, but British transistor amp manufacturer HH were using overdriven JFETs to provide their "Valve Sound" emulation very successfully back in the late 1970s. I wish I had a circuit to share with you, because this works really well in the HH, but they jealously guarded the technology by incorporating it into an encapsulated black box called the 'Tone Correction Module'. Since MAJ Electronics bought out the rights, they manufacture spare HH TCMs and, sensibly, see no reason to share the secrets of the TCM, which appears in the service manuals only as a box with numbered pins.
If the TCM in my HH ever fails, I'll replace it and reverse-engineer the old one, but I suspect it won't contain any major surprises. It's off-on only, but sounds magnificent. Mind you, their SS amps were state-of-art in the 70s/80s. I have to say that with sounds this good, I don't need the hassle of valves.
The idea of imitating amp models has been around a long time... that's actually part of the attraction of the Fet Muff... you can switch the diodes in and have a harsher type clipping or take them out for a softer amp-like overdrive.
The Mini-Tubes preamp with its 2-stage or 4-stage minibooster sections was designed with tone shaping from a Marshall Lead amp for a better distortion model and high-gain sounds.
The simple jfet CS stage idea has been adapted by at least one boutique builder for a line of pedals that imitate amplifiers.
But if you look at some of the solid-state amplifiers made by Fender, Marshall, etc., they have in some cases used the same procedure to make a solid-state amp. I don't have the exact models in front of me but if you trace through a couple of them you can see the influence from their tube amps.
-Jack
Ammscray,
The amp that I used to prototype is an old Randall RG35 SS deal. It's the least "coloring" amp I have. All tone knobs were set full up on the clean channel.
To answer the second question, we use cab sims to give a common reference point. Yes, there is sometimes drastic coloring of the sound with certain amps. There comes a point where it's hard to tell what is the amp and what is the pedal. To avoid this, we use cab sims direct to recorder. It's our attempt to provide an apples to apples comparison.
Quote from: bwanasonicCome to think of it- how come Marshall never did this themselves? Seems they went mostly the diode clipping route with their stompboxes, didn't they?
Kerry M
Interesting question...
I'm guessing their opamp approach has a lower parts count, for one, although I haven't sat down and counted the parts. The other issue is consistency, real important for large scale production. The CS jfet circuits sound great, but the jfet stages have to be biased individually due to variations in ea piece. This is fine for diy or even boutique/garage production, but my guess, once again, is that the labor involved here could be prohibitively expensive for a large scale production that competes with the likes of Boss, et. al.
Doug
Quote from: amz-fxI don't have the exact models in front of me but if you trace through a couple of them you can see the influence from their tube amps.
I found a quick example of a nice amp... the Ibanez GX-20:
http://www.mif.pg.gda.pl/homepages/tom/files/gx20.gif
-Jack
Thanks for the link, Jack. That's a nice site.
Doug
any word on that PCB???? :)
Quote from: ian87any word on that PCB???? :)
Yes, it's now available on the Thunderchief page: http://runoffgroove.com/thunderchief.html
Quote from: B TremblayQuote from: ian87any word on that PCB???? :)
Yes, it's now available on the Thunderchief page: http://runoffgroove.com/thunderchief.html
stoked.... placing parts order today ..... rubbing hands together in villainous fashion .... :)
Thanks for the Thunderchief!!!
Great idea.
I built one today but i used the BF 245. I adjusted the drain voltage to 4,5 (+- 0,3 V).
I have a biasing problem. The distorted sound fades away with some crackling at the end. Like a misbiased FET.
Especially on a low gain setting, at higher gain it is nearly ok.
Could someone post the Fet`s voltages?Is the BF 245 the wrong Fet?
Or should I use a different drain voltage?
THANK YOU!!!
:D
Eddie
well this thing looks great...although i m new to this i want to build one...
some questions...this circuit will give you the preamplification (the tone) of a marshall super lead.right?the gain in the schematic is the distortion of the super lead?any schematic for adding an eq to this...?
does anyone know other amp simulators like the super lead...somethin like fender or vox ac30???
I like the name (and the way it sounds). Wasn't the Thunderchief a fighter jet from the 50s?
My voltages on the BF 245 Pinouts, starting with the first, "left" BF 245:
1:
D 4,5 v
g 1,4
s 0,0
2.
d 4,6
g 1,15
s 0,0
3.
d 4,5
g 4,4
s 0,4
4.
d 4,46
g 1,146
s 0,0
Ist the gate voltage of the third BF 245 too high?
Please help me to find the mistake.
I measured all the resistors and checked the layout.
Thanks for any help!!
Eddie :?:
Quote from: Paul MarossyWasn't the Thunderchief a fighter jet from the 50s?
Correct! http://www.globalaircraft.org/planes/f-105_thunderchief.pl
However, I suggested it to Gary based on a friend's story of mistaking the AC/DC lyric "done dirt cheap" for "thun-der-chief."
We figured it was a pretty bad-ass and fit the pedal well.
To Eddie:
Make sure you use BF245A. B & C will not work (properly).
Did you used sockets? Can you switch around with the fets, to see it this makes any difference?
Try turning the pot of Fet 3 a bit to raise the voltage to 6 or 7 volts. Does this change anything?
Bye,
Joep
"However, I suggested it to Gary based on a friend's story of mistaking the AC/DC lyric "done dirt cheap" for "thun-der-chief."
He he... that's funny. 8) Dirty deeds thun-der-chief!
@Joep: I used Fairchild BF 245 A Fets. I had a look on the datasheet for the FET`s orientation. I checked it 20 times now.
If I raise the voltage to 6-7volts the sound disappears/fades away...
Thanks!
Eddie
No wiring mistake? The circuit is a bit complex around the 3rd fet....
Joep
BTW you can try raising the supply voltage to 15V. The turn-on voltage of the BF245 might be a bit to high.
Ajust all the trimmers to 7,5 now.
No sound at 7,5 volts.
Eddie :roll:
Hi,
Quote from: B TremblayQuote from: Paul MarossyWasn't the Thunderchief a fighter jet from the 50s?
Correct! http://www.globalaircraft.org/planes/f-105_thunderchief.pl
I just checked out the thunderchief link above. Did you checkout it's Armament? It is equipt with "One M6-1 20mm Vulcan cannon" maybe that's why it sounds so good! :wink:
Regards,
Will
B-52's are the loudest, a low end rumble that rivals your Dumble.
T-33's [AKA Tweetybirds] have a high end that kills.
I used to listen to these things going off about 50 times a week, frequently at 3 AM, 5 AM etc.
F-4's, SR-71's...the boys love to fly their toys...
Eddie, did you tried to replace the 3rd fet?
Bye,
Joep
Quote from: GaryAmmscray,
The amp that I used to prototype is an old Randall RG35 SS deal. It's the least "coloring" amp I have. All tone knobs were set full up on the clean channel.
To answer the second question, we use cab sims to give a common reference point. Yes, there is sometimes drastic coloring of the sound with certain amps. There comes a point where it's hard to tell what is the amp and what is the pedal. To avoid this, we use cab sims direct to recorder. It's our attempt to provide an apples to apples comparison.
Thanks for your comments Gary :)
Yeah the randall is pretty transparent compared to some, but maybe a little tube amp tone would be nice too...
My problem is that alot of the soundclips, especially the distortion and overdrives, sound very similar and I think the differences might be more easily heard with a speaker, like with some tube grind like you would have onstage playing loud...I know time is an issue with everybody though, and direct is quick!
For me, I know what all the vintage boxes sound like because I either have one or have had one, but for the newer designs it would be cool to hear how it's really going to sound in the real world, because I don't have the time to build every one that comes along...
Also, I think alot of younger or beginner builders also aren't hearing exactly what a vintage box really sounds like either, and that may adversely turn them off to something that's really what they want...
One example, is the tyco octavia clips you have there...again no offense intended but those clips don't really sound anything like a tyco, but it couldn't, just because of the way it was recorded...some people may say, "hmmm, that doesn't have enough octave for me", when the tyco's have lots of octave there when set up properly with the right amp...
Anyways, it's all just constructive criticism.:)
If you're interested, I would be willing to send you some clips of the vintage pedals that I've recorded, pro quality with amps turned up loud, giving an excellent idea how they really sound, and you could post them on your site if you like...
Peace
Good points, all... but there are other issues there...
I can make the same amp sound completely different depending on mic selection, mic placement, room ambience, mic preamp, mixer, etc...
there are an infinite number of variables that go into recording a guitar/amp combination - which is why no 2 records tend to sound exactly alike.
so, while I understand the desire for hearing a box through an amp, I also see the impracticality of it. as much as I can make something good sound great, I can also make something great sound like dogcrap.
"-)
Quote from: MarkBGood points, all... but there are other issues there...
I can make the same amp sound completely different depending on mic selection, mic placement, room ambience, mic preamp, mixer, etc...
there are an infinite number of variables that go into recording a guitar/amp combination - which is why no 2 records tend to sound exactly alike.
so, while I understand the desire for hearing a box through an amp, I also see the impracticality of it. as much as I can make something good sound great, I can also make something great sound like dogcrap.
"-)
Right, speaking for yourself of course... one of my backgrounds is engineering, when you've been doing it a very long time, with all those variables that are always present, still either a duck sounds somewhat like a duck, or it doesn't (and you're outta work!)
So that being said, with all the variables of recording a tycobrahe original, or clone on the computer or whatever, either it sounds close to it, or it doesn't...even though your EQ or choice of mic may be different from mine...I personally think that direct recording sounds way too fake and flat compared to miking...not even really in the "ballpark"
I'm saying that it would be nice to have soundclips of different things, that sound as close to real as possible...no, not everybody is an engineer, but what good does a soundclip do if it doesn't even get close??
Hope I was clear
QuoteIf you're interested, I would be willing to send you some clips of the vintage pedals that I've recorded, pro quality with amps turned up loud, giving an excellent idea how they really sound, and you could post them on your site if you like...
I would definately like to hear that!!! :D
It gives you at least some reference...
Quote from: AmmscrayIf you're interested, I would be willing to send you some clips of the vintage pedals that I've recorded, pro quality with amps turned up loud, giving an excellent idea how they really sound, and you could post them on your site if you like...
Send me an e-mail (info@runoffgroove.com) and we can discuss this further!
Quote from: AmmscraySo that being said, with all the variables of recording a tycobrahe original, or clone on the computer or whatever, either it sounds close to it, or it doesn't...even though your EQ or choice of mic may be different from mine...I personally think that direct recording sounds way too fake and flat compared to miking...not even really in the "ballpark"
I'm glad you brought this up, because I can't stand the sound of direct to soundcard clips. In addition to miking an actual amp, it would be nice if clips featured a bit of the raw amp sound for reference. I believe Tone Frenzy uses a mic'ed amp for their clips.
Kerry M
Hello Hello--
There used to be a time when guitar players played through nothing but tube amps ['cuz that's all there WAS]. Jump ahead a few decades and we have people trying to emulate the sound of these tube amps by using computer technology. All this technology allows people to sit down at a desk and and "create" [cut-and-paste] some "music" that does not involve other musicians [a lot of it actually gets released as "product".]
I make no apologies to anyone for saying that most of this stuff is crap.
Sometimes I will be in a studio using Pro Tools or whatever and all I want to do is make everything sound like I'm playing through a cranked Marshall. [ This usually means I'll have to bring in the Marshall myself 'cuz there won't be one in the studio anymore. ] Now, this is a lot of trouble, but it's worth it to me to use the real deal instead of sitting there with headphones on trying to get "my sound" with a piece of technology that doesn't move any air!
I have yet to hear ANY good, pro quality guitarist [over the age of 20...]
say that he wants his Marshall / Vox / HiWatt etc.... amp to sound like a transistor wannabe. I do, however, see that modern technology dictates
that the wannabe MUST sound like a real tube amp cranked up.
So..yeah, I wanna know what a circuit sounds like when combined with a good tube amp [especially since all the older circuits were designed to be played with tube amps..]
Sad-but-true........Eric Clapton made his career on being influenced by people like Buddy Guy and NOW Buddy Guy has made his career on being influenced by Eric Clapton!
Brian.
No offense, but some of these posts sound like people complaining about Brian and Gary's recording techniques? Excuse me, but they are providing a great service here. Why all the bitching? You don't have to build their projects, and after the direction this thread has taken, you can bet they think twice about posting another project. These guys come up with a new project, lay it out for you in perf, recommend mods, and give you sound clips. Who else does this? What more can you reasonably ask? I'm sure they will williingly give you a full refund of the money you paid them for this service they are providing to you.
For some perspective, how many pedal manufacters provide you with sound clips of their products through a tube amp?
I want to say to Brian and Gary, you guys are the shiznit! Keep up the good work. I've had hours of enjoyment from not only building, but playing your projects. I'm gonna have to go out and buy some runoffgroove t-shirts for my family members to give you a little of the support you so richly deserve.
Quote from: javacodyNo offense, but some of these posts sound like people complaining about Brian and Gary's recording techniques? Excuse me, but they are providing a great service here. Why all the bitching? You don't have to build their projects, and after the direction this thread has taken, you can bet they think twice about posting another project. These guys come up with a new project, lay it out for you in perf, recommend mods, and give you sound clips. Who else does this? What more can you reasonably ask? I'm sure they will williingly give you a full refund of the money you paid them for this service they are providing to you.
For some perspective, how many pedal manufacters provide you with sound clips of their products through a tube amp?
I want to say to Brian and Gary, you guys are the shiznit! Keep up the good work. I've had hours of enjoyment from not only building, but playing your projects. I'm gonna have to go out and buy some runoffgroove t-shirts for my family members to give you a little of the support you so richly deserve.
Dude you are so much missing the point, and the bleeding heart **** doesn't get any points...nobody is bitching and nobody is complaining, read the posts carefully, suggestions are being made here simply to make the listening and evaluation of a particular pedal easier and more decisive for some...what's wrong with that??
I have been building pedals and helping people with their projects for 20 years + way before the internet and this forum was even an idea so just listen, it could benefit you...
Without constructive criticism and input from other people nothing would evolve and things would stay the same and be stagnant...
I'm glad this thread has taken this "direction" as you call it, it's about time...there are lots of people here besides beginners you know...we were here first as a matter of fact!...it would be a real benefit for people to hear what a pedal really sounds like before they build it, or shell out big money for an original, or whatever...that's the point...
B Tremblay, you have e-mail... I can provide you with soundclips of the following vintage pedals (and clones if needed) for your site:
Rangemaster Treble Booster
Dallas Arbiter FF
Vox Tone bender
Vox Treble Booster
Various Color/Solasound pedals
Roland jet phaser
Various Boss distortions and overdrives
Various MXR pedals
Various octavias
Various wah pedals
blah blah blah the list goes on...peace
hey thanks to Brian Wenz for making the appearance! Where's everybody else?
Quote from: javacodyI'm gonna have to go out and buy some runoffgroove t-shirts for my family members to give you a little of the support you so richly deserve.
I had never seen the merchandise section before; those shirts are great! I'll definitely be getting one soon. Add my vote to the "you guys rock!" list. :)
Alex
Sorry if I missed your point Ammscray. I guess your last post expressed that point a little more succinctly than your previous posts. I think we can all agree that a pedal is generally going to sound better through a tube amp, can we just call that a given?
Also, I never questioned your experience (you made it very clear in every post you made exactly how much experience you have) and constructive criticism is great, but when doling out "constructive criticism", it is usually a good idea to point out what people are doing well, otherwise it can come off pretty negative.
I'm not sure I understand your bleeding heart reference?
One last thing, I'm not sure many of you have taken into account the amount of work these guys have put into not only putting together the projects, but also setting up their site. They also have to pay for storage and bandwidth, which I'm sure comes out of their own pockets. They deserve a lot of kudos for what they do for OUR community, which was my main point. Sorry you seem to disagree with that Ammscray.
Thanks again Brian and Gary!
Quote from: javacodyNo offense, but some of these posts sound like people complaining about Brian and Gary's recording techniques? Excuse me, but they are providing a great service here. Why all the bitching?
Alas, the pitfalls of trying to communicate in this medium. I'm not sure exactly why you perceived bitching, but that was not what I was talking about. The subject had been briefly changed from *how bitchin' the Thunderchief and Runoff Groove is* to *how direct to soundcard clips of certain pedals sound like ass*. The general topic of establishing a frame of reference for clips of pedals then ensued. If no one had ever heard a Rangemaster before, and I posted a clip of Rangemaster-cabsim-soundcard, It would probaly elicit a much different response than a clip featuring mic'd Rangemaster-Marshall Plexi. It's for all practical puposes an entirely different effect. Since Runoff Groove is a major frame of reference for the DIY community, it might be worth discussing the way some of these pedals get heard.
Kerry M
Quote from: javacodySorry if I missed your point Ammscray. I guess your last post expressed that point a little more succinctly than your previous posts. I think we can all agree that a pedal is generally going to sound better through a tube amp, can we just call that a given?
Also, I never questioned your experience (you made it very clear in every post you made exactly how much experience you have) and constructive criticism is great, but when doling out "constructive criticism", it is usually a good idea to point out what people are doing well, otherwise it can come off pretty negative.
I'm not sure I understand your bleeding heart reference?
One last thing, I'm not sure many of you have taken into account the amount of work these guys have put into not only putting together the projects, but also setting up their site. They also have to pay for storage and bandwidth, which I'm sure comes out of their own pockets. They deserve a lot of kudos for what they do for OUR community, which was my main point. Sorry you seem to disagree with that Ammscray.
Thanks again Brian and Gary!
I wasn't trying to take away any kudos, I'm very aware of the services these guys are providing and I think they got many great pats on the back for it just in this thread alone...
but we know that already, I was trying to bring a new point of view to light...at this point I don't want to take any more time to explain why I said what I said, I'd just like to see where this goes now that I've contacted B Tremblay about the clips...thanks for your reply
very nice!!!
everything i tried from you guys is great
thanks
keep up the good work
Hello Hello Again--
Yeah, I just want to make it clear that I am not slagging Runoff for ANYTHING that they have done. I was just reporting on the state of things in general and how I prefer to hear things!
Brian.
While we recognize the value of sharing Ammscray's vintage fx sound clips, runoffgroove.com will not be hosting them. We've chosen to continue concentrating our creative energies on circuit development.
We do realize the necessity of sharing representative clips of vintage boxes, so we're hoping that a member of this community can assist Ammscray in making them available.
Also, feedback on the site is always valuable to us and accurate samples of our circuits will continue to be a priority.
Finally, many thanks to all who have supported the site! Knowing the content has been useful and fun makes it all worthwhile for us.
To the lab experiment, level playing field approach for recording sound clips: With all the myriads within myriads of possibilities for outside elements to influence the sound of a circuit, it makes perfect sense to have everything outside the cct comparisons to be controlled elements.
That being said, most of these circuits were designed to have outside elements influence their sound.
I use tube amps for testing. Cranking the amp even a little brings out tones that are created or influenced by the effect circuit, the amp, guitar, speaker, effect circuit, cables, air [moisture,pressure etc], strings, pickup height....I'm sure there are other things influencing the perception of sound.
I think most of us here, deep down either use nice tube amp, or pick up enough info to begin wondering how much to want for tubes]..
Output tube driving speaker:..the most applied [or emulated] guitar effect of all time.
"Sounds just like a tube amp"
Great Job Recording!!!
I wish I could get such wonderful playback sounds.
Thunderchief soundclip.. has a great replay value, I load and listen when I need a charge...!!!
Sound clips are a funny subject because everyone wants something different from a sound clip. Some people like the little 'mini-songs', others want to hear just a clinical run-through of putting a pedal or amp through it's paces with nothing else to distract it. Some people want to hear it through a tube amp, others direct for comparison purposes, others through a clean SS amp. The only thing that is consistent is that you won't be able to please everyone.
In the end, I don't think soundclips really tell you much about how a particular pedal is going to sound through your rig, with your guitar, in your room, at your gig, etc. They just give you kind of a hint or a point of reference to compare with other things.
When I do a soundclip I just try to bring out the best in the pedal, showing it in the best light, whatever it takes except for post-production eq-ing tricks and etc. It's just meant as kind of a snapshot of the pedal's potential.
In general, for my "amp-emulators" I like to use a clean SS amp. Sure, it sounds good with a tube amp, but tends to get colored by the amp sound so much it ends up just being another facet of that particular amp's sound. OTOH, if I can show it making a sterile SS amp sound "tubey" or whatever, than that's really showing something. But, IMO vintage fuzzes and boosters were -made- to drive tube amps, so recording them with anything else just doesn't make any sense. Their purpose in life is to drive a tube amp, AFAIC. To me, it's just a matter of doing things in the proper context.
I mic all the clips, IMO, I don't like the sound of direct and don't use it anyway. Comparing direct recordings doesn't help me since these circuits sound a lot different through a mic'ed amp. I don't mind modulation effects recorded clean and direct, though. That's just my opinion, and I have many. :D
I like doing little 'mini-songs' because there is an emotional connection I have with music that I can't separate when listening to clips. I love tonefrenzy, great resource and site, but after hearing 2 or 3 "test suites" of overdrives my ears go numb. I just can't concentrate on it anymore. And all the little subtle nuances and differences kind of get lost in the noise anyway, when you consider the variables of guitar, amp, and etc between what I'm using vs. what was used in the clip.
Anyway, that's just my 2 cents, no flames intended. This is a good discussion. I would love to hear Ammscray's clips if they could get hosted somewhere.
Doug
I;ve built many Runoff Groove Effects based on the soundclips.
Spent hours just listening to them, I appreciate them very much, also that they are all done with the outside elements [sim and soundcard] stated.
This puts all the recorded effects on a level playing field, even tho that may not be the one you or I use, or the one that a particular effect shines best in.
Once you stray from a given set of variables, the possibilities run wild.
I like the idea that the soundclips are done in a controlled environment.
Does anyone know where to get the .68uF caps that are in this and number of other projects of late? I would prefer the smaller Panasonic (F) type if possible. It seems Mouser only has the larger higher voltage types, & Smallbear doesn't have them at all..
Regards
RDV
Let´s concentrate on the thunderchief!
Could someone do me the favor and post the D/G/S Voltages of the third Jfet( third Jfet from input view)?
I have the sound of a misbiased Jfet and I think that the third one is the problem.
See my earlier post in this thread(page 4).
I measurded these voltages(third BF245A):
d 4,5
g 4,4
s 0,4
Yes i checked the orientation. I changed this Jfet too (used a new one).
I got this unit 90 % working and I want to "win" this time! :lol:
THANKS!!!!! :idea:
Eddie
Quote from: EddieMy voltages on the BF 245 Pinouts, starting with the first, "left" BF 245:
1:
D 4,5 v
g 1,4
s 0,0
2.
d 4,6
g 1,15
s 0,0
3.
d 4,5
g 4,4
s 0,4
4.
d 4,46
g 1,146
s 0,0
Ist the gate voltage of the third BF 245 too high?
Please help me to find the mistake.
Eddie, first off let me start by saying that you are subbing for an essential part of the design. I realize that you may not be able to get J201s but you really have to use the right parts if you expect to replicate the sound of any particular design.
That said, ALL of the FETs are misbiased. For a JFET to work properly, the gate voltage has to be BELOW the source voltage. This makes me think that you have the pins mixed up, more specifically the gate and source terminals mixed up. If you look at the schematic there is no way for any of the JFETs, except the third which would still be below the source, to have its gate be anywhere but at ground. Double check the pinout, I think that you will find that you have the gate and source terminals swapped.
Like I say on my schematics: "Experimentation,
once you get the circuit up and running as shown, is encouraged."
Thanks Jay !
I`sorry I mistyped the voltages, G was Source (mixed up by typing..)
So here are my "new" values:
1.
D 4,5 v
S 1,4
G 0,0
2.
d 4,6
S 1,15
G 0,0
3.
d 4,5
S 4,4
G 0,3
4.
d 4,57
S 1,14
G 0,0
It is very hard to get the J201. So I thought I could use the BF245A.The source voltage of the third is a higher value.
Thanks for your help!
Eddie
OK then. The third JFET is going to have a significantly higher source voltage because it has a higher resistance on it's source. The third one has about 10k of resistance on it's source whereas the second and fourth have 1k and the first has 2k7.
Looking at the BF245A datasheet here (http://www.semiconductors.philips.com/acrobat/datasheets/BF245A-B-C_2.pdf) you will see that the Vgs(off) value for these JFETs can vary from -0.25V to -8V. This is a huge swing and unfortunately one of the main problems with JFETs. If you have one in that has a Vgs(off) on the lower end, your JFET is biased so that it is always off. You may need to try several different BF245As until you get one that works.
This is a good example of why to use the parts specified. Sorry to beat the horse, but there is a reason the designer's picked the particular parts they did: because they make the circuit work. Subbing for JFETs is a generally bad idea; part variation is bad enough within the same part type, forget trying to make another part work!!!
Good luck.
I agree with what you are saying about using the right parts, Jay.
But his 3rd stage should bias up okay. The 1M gate shunt resistor is referenced to the bottom of the 470 source resistor. So it should bias up like it has a 470 source resistor.
However, now that I think about it, I had a problem with excessively large "tail" resistors in the "PI" when I designed the Meteor. Hmm...
Doug
[sings loudly to the tune of when the saints go marchin in]
all those soldering irons,, gettin cold, all those circuits getting old
im gonna turn off my computer and take my a** back to work
hmm figured if i didnt' do it Tom Would have
Eddie,
I'm pretty sure there was a germany webshop were the sold the J201 and some other US-type transistors. Only I can't remember were, maybe some other forummembers remember??
You can always order some from Small Bear (http://www.smallbearelec.com) They are pretty cheap. Don't formet to oerder a few more for future Runoffgroove projects.....
Bye,
Joep
Quote from: Doug H
However, now that I think about it, I had a problem with excessively large "tail" resistors in the "PI" when I designed the Meteor. Hmm...
Doug
I noticed this, too. There is a point (over 10k?) where the source resistance becomes too large to let the jfet bias correctly.
Eddie,
Here's voltages from the prototype Thunderchief's 3rd stage:
D 4.3 (used a fixed R instead of a trimmer)
S 0.5
G 0
Quote from: GaryHere's voltages from the prototype Thunderchief's 3rd stage:
D 4.3 (used a fixed R instead of a trimmer)
S 0.5
G 0
OK, now I am really confused. I didn't think about it but Doug is right, it should be like the source is biased with a 470 ohm resistor. But if Gary's voltages are right, and there is no reason to think that they aren't, then if the gate is at ground, the feedback to the third stage is being shunted to ground.
I'm all kinds of confused on this...
Must be because it is Friday.
Thanks for posting the voltages.
My Source voltage is over 4 volts. Maybe I have something wrong at the Source resistors (470 , 4k7,4k7, Ground).
What is more likely, something wrong at the source or the wrong Jfet?
I have found a online shop in Germany (sells j201)
http://www.banzaieffects.de/parts/transist.htm.
Eddie
Quote from: Jay Doyle
But if Gary's voltages are right, and there is no reason to think that they aren't, then if the gate is at ground, the feedback to the third stage is being shunted to ground.
I'm all kinds of confused on this...
Must be because it is Friday.
Sorry, I forgot to go another decimal place. The gate of the proto is actually at 0.08V. Not much, but some difference.
I had an earlier build that had these pin voltages. It works fine and sound similar, if not the same. (these are voltages from an earlier build, not the one in the clip)
D 4.5
S 2.3
G 1.2
No matter which jfet I stuck in there, when biased at the drain to 4.5V, the source and gate always set around these points. It doesn't make much sense on the surface, does it? Anyone want to take a shot at explaining this?
Eddie: That's the one!
The pin voltages for all four FETs have been added to the article: http://runoffgroove.com/thunderchief.html