toneblaster mk 2.5

[pinkjimiphoton]

here ya go. should be good to go. yes, could probably make the vero a little smaller.
schematic to follow soon.

this circuit has been thru some changes since i started it, a lot of discovery along the way including a few epiphanys where suddenly esoteric info made more sense..
like adding the trimmer to the original version's attack control to dial in the response of that control...i could replace it with a 22k resistor, but i like being able to tweak it.
it borrows the old "britface" temp stabilization mod for q1, as it's an npn germanium.
i grounded the emitter of q1 for max gain, which seemed to work out well.
found that using a diode clipper from e  of q2 seemed to add a  nice compression and sustain.
a broad range of fuzz sounds, from relatively clean to putrid jagged filth that would make Lucifer's Trip smile is available with a tweak of tr1.
tr 2 will let you vary the attack...and the compression...as well as the overall voicing of the fuzz. the larger the resistance, the less effect the attack control will have, but the greater the compression available will be.
tr3 is more for fine tuning, but seems to help get it the last "little bit" of balls available.
the output buffer helps add a little sparkle, and adds a little to the available grind.
this thing sustains like a mother@#$%er, but never loses the fuzz edge...you can dial it from clean, to overdrive to crunch to distortion to fuzz to shattered ice right from your guitar. i used this thing last nite live and was actually amazed it worked as well as it did..
i found optimal settings were 3 o'clock on attack and volume, and 12:00 on volume.
anyways, i think i like it.
the original vision was to add a rangemaster to a two tranny tonebender, but i ended up basing it on the silicon tonebender andrew carrell and ricky d. vance worked up a long time ago.
my total lack of knowledge really came into play as this thing developed over the last 2 years..and the same basic cct kept evolving.
while the one i'm rocking actually has a daughterboard for the buffer, the vero layout i worked up has it all on one board.
since i haven't built this version yet, it's not ver-o-fied, but i believe it to be good, as there's not too much i could screw up on it.
nice sounding cct...have a play on the breadboard, criticisms and advice as always gladly accepted!!

and with no further babble, here ya go...the toneblaster mk 2.5, probably the closest to an almost original circuit i've come up with (which isn't saying much)



schematic to come, and of course, stupid pedal trick...

if you build this, please let me know!!

peace out, happy xmas/kwanzaa/chanukah/whatever floats your boat. just have a decent day!

EDIT> CAUTION TO NOT MISS TRACK CUT BEHIND RESISTOR AT C9 ADDED..

[pinkjimiphoton]

here's the schematic....thanks rutabaga bob!!

[Gus]

The first stage should be OK without the Ge diode (470K C to B, 100K B to ground) Have you tried it with out it and done a temperature test?

What does the  1n4148 (left in the schematic) do in the Q2 emitter leg?  looks like an extra part to me.

You can do better with the EF buffer at the end.  Reduce the 100Ks values add a cap from the center node to ground.  Adjust the DC bias more toward +9 as drawn the Emitter sit about .6VDC less then 1/2 the supply voltage(change the ration of the resistor drawn as 100ks).  Hint look at the sims I have posted at this forum, look at the buffers for ideas.

C5, R11 where did that idea come from?

Have you tried a Silicon transistor at the first stage?  Try something like a TIP29.
The way this circuit is drawn it looks to me that it will not make much difference maybe adjust R7 and R3 for the collector current and gain you want.

NOTE  R7 is part of the DC bias and feedback for setting the gain of Q1, this stage interacts with the guitar/cable RLCs before it.  This looks like it will work OK with a guitar before it but what happens when you use something like a TS before it with an output buffer and low output resistance.

A EF note R3, R4 values/ratio

[pinkjimiphoton]

hi gus!
thanks for looking at this for me, and the great feedback...i'll try to answer where i can below...

The first stage should be OK without the Ge diode (470K C to B, 100K B to ground) Have you tried it with out it and done a temperature test?

i added the diode way back when i first started messing with this project about a year or so ago, after i had so many problems with my fuzzface and the cold.
not knowing what i'm doing, i figured i'd try it. i haven't tried a temperature test, but it seems to be stable in my house, on stage, even when it's been left in my car's trunk overnite and is freezing cold. my fuzzface would have a gas attack over that!!

What does the  1n4148 (left in the schematic) do in the Q2 emitter leg?  looks like an extra part to me.

i thought so...originally, i tried to use a diode clipper i had twisted together, just experimenting. i also tried grounding the emitter of q2 directly, but it lost all its dynamics, unlike q1 where it seemed to bring it to life. i don't know what it's doing, but it definitely has an effect on the sound, i guess the diode only conducts when the signal level is pretty high. half wave rectifier i'm imagining?  you answered my question about which of the diodes could be eliminated, thanks bro!

You can do better with the EF buffer at the end.  Reduce the 100Ks values add a cap from the center node to ground.  Adjust the DC bias more toward +9 as udrawn the Emitter sit about .6VDC less then 1/2 the supply voltage(change the ration of the resistor drawn as 100ks).  Hint look at the sims I have posted at this forum, look at the buffers for ideas.

this particular buffer was just a daughterboard i had added when i first built this...trying to get more balls out of it. originally, this thing sounded more like a compressor than a fuzz!! it was based on the silicon tonebender schematic by andrew carrell, but i wanted to go with ge in the front end...and, being clueless, i just kept messing with it til it sounded right, it's been a work in progress of intermittent tinkering ever since.
what i've learned <slowly> thru this time came into play...was a major epiphany for me when i realized how to make the attack control work the other day. it DID, kinda sorta...before. but it was almost imperceptable. i was using a 5k pot, which was way too big. first thing i did was try 1k, which made it better, but still hardly noticeable. i looked at the attack control circuit, and realized the voltage divider of r9 and r10 was sucking the life out of it, so i figured the quickest way to check was to use my handy dandy roach clip leads and stick a 100k pot in parallel with r9.
i dialed it in until the attack seemed to work,  and measured the pot...was reading 26.66k...so i used a parallel resistor calculator and discovered in parallel it was around 21.xxx k...i figured i could use a resistor around 22k or so, but i liked the pot...you can really dial in the compression as well as the attack of the circuit with it. again...all happy accidents, i am in no way shape or form anything but a crude hack still. but that epiphany marked a turning point, where suddenly for maybe the first time i made the right mental connection to figure it out.

C5, R11 where did that idea come from?

that was on the original schematic i had based this on, i think. is it unnecessary? again, gus, i'm a hack...i'll sit and tinker, swapping parts in and out until it sounds like something i like.
doesn't mean it's any GOOD!! but this thing sounded great last nite at the gig.
i didn't even use my pedalboard...this, one of my wahs, and an echoplex into my hot rod princeton. i had some of the best tone i've had in years. i never turned this pedal off all nite!!
turn down for clean, turn up for scream. i was surprised how well it works. when the guitar is cranked, it's a little "edgy", but in a kinda good way. and it never seems to forget it's a fuzz.
when the guitar is pegged, it's a sick unit!!

Have you tried a Silicon transistor at the first stage?  Try something like a TIP29.
The way this circuit is drawn it looks to me that it will not make much difference maybe adjust R7 and R3 for the collector current and gain you want.

nope, never tried silicon in the first stage. these are the original transistors i had started the project with. only q1 is socketed. the others are soldered in.
do you mean i could use say, a 500k pot there as a voltage divider instead of r7 and r3? that would be cool, could dial it in for different transistors. but... doesn't grounding the emitter of q1 give it max gain anyways? it had ZERO balls before i did that. the wimpiest fuzz of all time, like i said, more of a compressor than a fuzz.

NOTE  R7 is part of the DC bias and feedback for setting the gain of Q1, this stage interacts with the guitar/cable RLCs before it.  This looks like it will work OK with a guitar before it but what happens when you use something like a TS before it with an output buffer and low output resistance.

you CAN'T. it has to be first, like a fuzzface. if you put it before anything else, it's ok...unless it's a fuzzface. the buffer totally makes it sound like poo. but, a fuzzface before it (no buffer) seems to be fine!! it is very interactive with my guitars...i've played it with my strat at rehearsal monday, and my sg at the gig last nite, and it was insane.
if the guitar is turned low, you can get any shade of grit completely with pick dynamics. i don't know why, but it does it! when the guitar is cranked, same phenomenon... play real light, and it's clean...and grinds more, and gets louder, the harder ya whack it.  anyways, it seemed to be ok with a crybaby in front of it, but nothing else seems to work really. this thing wants to be first in line. if using it as a pure fuzztone (like, guitar on 10) it's probably fine. but i'm all over the place with volume, and it seems to respond really well to the guitar dynamically.

A EF note R3, R4 values/ratio

i would have to build it gus, i don't know enough to look at stuff yet and really understand it.  so the ratio of a voltage divider in a case like this should be around 1:2? or am i not understanding? quite possible...no rocket scientist here!!!

not sure!

this thing as drawn/laid out is just what i had cobbled together, so i know there's room for improvement. thanks so much for taking the time to help me bro!

i think when/if i build another variation, i will try the changes you suggest. this thing sounds freekin' great, so anything that will improve on it is welcome!!
stupid pedal trick to come soon!




[/quote]

[pinkjimiphoton]

here ya go, video or it never happened...

let me know whatcha think...

[Gus]

To the best of my knowledge I was the one who first posted the lowpass like C5, R11.

Look for the 3 transistor fuzz and the rocket  and other FF like fuzz circuits I have posted over the years.

Look at how I wire a bias control to a FF like circuit, again in my sims and posts at this forum and also in schematics in the schematics link at the top off the page

Look at the Hot Silicon schematic for what I think is a good first stage for a Si TB like circuit. I designed that first gain stage for a gain of about X10 and an input resistance that can work with a guitar or another effect.  Doug took my basic 3 transistor circuit and add a tone control and another stage and adjusted for something different

Have you removed the one reverse biased diode in the diode pair in the emitter leg(left one) to see if the sound changes?

[pinkjimiphoton]

To the best of my knowledge I was the one who first posted the lowpass like C5, R11.

it was on the schematic i referenced, i don't know who did it originally, or if it was even part of the original circuit, bro...here's the schematic i based my pedal on originally, you'll see the r/c network is on it...i think i first looked at this about a decade ago when i first got on line. if it's yours, props, cuz it does seem to sound great!

Look for the 3 transistor fuzz and the rocket  and other FF like fuzz circuits I have posted over the years.

i think i have every single one in my archive of effect schematics. i am just beginning to get savvy enough to recognize parts of circuits and where they come from. i will look at them, i've been planning on trying several, but i haven't been able to build much lately, the girl got a little pissy about me taking up the dining room table for 3 - 4 months at a time.

Look at how I wire a bias control to a FF like circuit, again in my sims and posts at this forum and also in schematics in the schematics link at the top off the page

Look at the Hot Silicon schematic for what I think is a good first stage for a Si TB like circuit. I designed that first gain stage for a gain of about X10 and an input resistance that can work with a guitar or another effect.  Doug took my basic 3 transistor circuit and add a tone control and another stage and adjusted for something different

i have that, i'll look at it, thanks gus. but remember...comprehension here is just dawning ...just barely.
did ya get a chance to check the video? maybe it's just me, but to me this thing sounds a bit different from all the other fuzzes i've built so far.

Have you removed the one reverse biased diode in the diode pair in the emitter leg(left one) to see if the sound changes?

nope, haven't bothered, figuring if it's not broke.. but i seem to remember trying a jumper, a pot, a couple resistors and  a couple diode types before settling on the diode clipper i put there. it may be me, but i thought it had a little more compression with the clipper, as opposed to a resistor or jumper.

10,000 monkeys with 10,000 typewriters.

when i build another, i will try it with the single diode and see if it changes. i expect it will, a little.

what would be a good way to raise the input impedance of the cct? is it something my non-intelligent self will figure out looking at the examples you cited?
will it change the tone of the pedal? cuz i really, really dig the sound of this thing!!

too many questions, i know...thanks bro~!!

[kodiakklub]

jimi: im trying to draw up the schematic in eagle, but your handdrawn doesnt match up to you vero.
-where are the other 2 trimmers on your schematic?
-the pot values are conflicting, they actually match the trimmers
-tr1,2,3 = vr1,2,3 im assuming

love the sound on the video, really want to build this but can you clear up some of these questions? thanks so much.

[pinkjimiphoton]

hi bro,
the schem was an earlier version RutabagaBob worked up for me.
at that point it didn't have the trimmers.

what you hear on the demo is the circuit as it appears in the vero layout. i don't know how to do schematics in any of the programs i've tried, sorry.

the trimmers are indeed probably labeled vr1,2,3, etc instead of tr1 , 2, 3...

the full size pots are 1k for attack, and 100k for tone and volume.

first trimmer is 100k going to c of q2. i may have used 50k, but if i remember, i had to go up to get it to bias right. (it was based on the schematic by andrew carrell in this thread)
vr2 and vr3 are mislabeled on the vero, sorry...but the values are right.
there was no vr2 (the one at the bottom of the vero layout) originally, it was just a 100k/330r voltage divider. the attack control wouldn't work right, so i played with it using a 100k trimmer. 22k is just about perfect, (you could replace 100k r9 and that trimmer with a 22k resistor) but i like being able to dial it in with the 100k trimmer there by ear.

vr3 as shown on the schemo is 1k. you can probably use a resistor instead of the trimmer if you want, it's fairly subtle.

i would really appreciate it if you post your schemo when done!!

btw... i don't use r extra in my build, rutabagabob added that.

the buffer circuit is after the output of the volume pot, but before the switch.

i'll attach the vero for that; it's on a daughterboard on my build, but i included it all as one board in the vero on this thread. the buffer was one of the first things i tried to layout, so it's kinda rough, but easy enough to figure out if ya follow the components like a bunch of stompboxes.



sorry about the discrepancies, didn't mean to be obtuse!!

hope ya like it!

[Quackzed]

it was on the schematic i referenced, i don't know who did it originally

I believe the original version of that schematic was drawn up by the late great RDV!
sadly we lost him a few years ago. he had a site 'fatboy effects' that is still there but many of the images he had on his site now only exist in other forumites pc's... he was a good guy, you woulda liked him. he'd probably really dig that people were still building and modding from his schematics. i had also built his npn silicon tonebender and he suggested i place the schocktave circuit after it. holy massive octave down with that combo. if you happen to have an octave divider anywhere, try it! 

[pinkjimiphoton]

i got all his stuff, actually, i found reference to them and joined a site just so i could see 'em. got them on my harddrive in fact.
yah, it's a great schematic..it got me a working pedal! it just took a year or so for me to figure out how to "tune" it, is all.. i mean...here's the original:

very different sounding from this one!!

then the second version:

i mean, listening to the original, and then the second try, this ain't even in the same ballpark anymore.

and the video i did was with a dead battery, for god's sake. fresh battery, it's like a big muff pi that can clean up like a fuzzface and not sound like it's buried up to it's neck in mud!

the final evolution...quite a change in this thing!!

please let me know what ya think if/when ya build it. it has an "edge" that doesn't translate as well in the video..it can get pretty harsh, like jagged shards of glass mixed in. i LIKE that. but i'm a sick, sick guy...

[Quackzed]

yeah, that last version definately sounds sick! nice licks as well. And that tele has me gas-ing for a tele.
ot-  i just re-re-painted my homemade strat back to olympic white(sort of) after it was all sparkly with orange flipflop and red silver orange blue sparkles. sounds cool but from ten feet away it was pink/purple
so i needed to rerefinish! then just as the paint was drying it fell from the holding jig and got a few decent scars... oh well, just a head start on that relic vibe ...  sorry for the ot. just needed to vent.
anyway that really does have a nice tone, warm and edgy at the same time, sounds like it will really cut through in a band situation. rolls off real nice as well.

[pinkjimiphoton]

bro, i feel your pain in an off topic way. i bought a firebird kit. beautiful. spent a week or so just sanding it so it was smoother than a baby's ass.
put a beautiful hand-rubbed, old-school sunburst on it, french polished...cabernet (a purple reddish brown ) to red mahogany sunburst. it looked like it was dipped in blood almost...it @#$%ing glowed.  i finally had the burst looking great.

i steel wooled it down. all good.

hung it, and went to touch up a couple spots. ooooops.

forgot the goddamn TACK CLOTH!!!! O NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO!!!!!!!!!!!!!


yep... ended up getting steel wool filings into my beautiful sunburst i'd worked on for over a week to get just right, with probably 20 coats. ruined.

now i gotta zip-strip it down to bare wood and start over again. all because i forgot to use the dang tack cloth.

so believe me, i feel ya!!!!!! now i gotta wait for spring to fix it.
ay yi yi yi...makes my bwain hurt.

anyways, yah, the pedal...quite an evolution. in a live situation, it's the best fuzz i've used. it sounds like an un-muddy big muff with a lot of compression and high end chime, and cleans up like a good fuzz face. totally touch responsive.

i don't know what i did or how, really...i suspect a lot of it comes from the diode clipper to ground off of q2. i bet if i put a trimmer there too, i could adjust the compression of the circuit. i'm pretty sure that's what's happening with them diodes there, and why it cleans up so nice but stays so sensitive.

gonna build another one and see if i can verify the design.

[petey twofinger]

ouch !!

i stuff like that i do it all the time . and somewhere back in my head , something goes off like , " slow down , you are about to do something you will regret " . i swear a few times i have caught myself , slowed down , looked and thought , but those moments " i had the tack cloth in my hand " or whatever .

i think you just cant get too comfy .

confidence should be low , at all times , lol .

that t-bird kit idea sounds cool , you used to have one , no ? i dig those . played an epi tbird four string , goth one , at the pawn shop outlet yesterday , surprisingly smaller body / less weight than i had imagined , oh and srry for ot , again .

amazing how well it cleaned up , no difference on my end . i do not own a fuzz that can do that well ...

[pinkjimiphoton]

petey, did you build one of these, and it's not cleaning up, or am i misunderstanding you?

[kingswayguitar]

this thing is stacked
thanks so much for sharing the results of all your hard work with us mortals
its worth watching the entire 12mins because theres at least 1 memorable quote per minute
"this thing should rip your head off"
"the volume makes it loud"

cheers

[pinkjimiphoton]

i'm a mortal too bro, so it's all good. i wouldn't be here without standing on the shoulders of the giants before me, and a curious need
to find the perfect fuzz by building every @#$%ing single one i can, and breaking it til it sounds good!

glad ya likes the SPT's dude. peace.

[kodiakklub]

im still working on the eagle schem and PCB layout but its gonna be a couple more days. and i have to figure out how to read a vero schem/layout. but i am very excited to build this puppy. thanks jimi.

[Mustachio]

Jimi man this thing sounds sick! Love it! First the harmonic perc and now this! I cant keep up I gotta build em both. Gotta find the time. Might have to give up sleeping for a while 


Always great playing man!

I'm really in need of some lead tones. I think like many of you I'm always looking for that sound, ya know what I'm talkn about the sound that makes you look like you smelled something. Haha

[kodiakklub]

jimi: is VR1 trimming between the 9V rail and ground and feeding Q2? or did you miss a cut on the vero layout?

edit: nevermind. its in the notes. my bad.