Burnski Buzzaroundski

[digi2t]

I was looking at my brother Jimi's Liberal Komrade video the other day, and I decided to mess around with an established circuit as well. In this case, the Burns Buzzaround. I used this schematic;



Initially, I tried a trio of 2SB176's, but it didn't give me anything to write home about. Then, on a whim (remembering Jimi's video), I decided to try some Russian MP20B transistors instead. I got a crapload of them, for next to nothing, sometime ago for another project.

Well... I'll let you be the judge...

Seems to give a Muff a run for the money I say .

[glops]

Love that circuit.  Now you gotta try out the Dizzytone.  More hairy.

[LucifersTrip]

Sounds  very cool...it is really an easy germanium circuit to get to sound great, since you really only need to find 1 transistor that works well.

Since Q1/Q2 are a darlington pair, almost anything with low leakage (even gains as low as 30-40) will be cool. It's only Q3 that you really have to hunt for. I would definitely try a bunch in the Q3 slot before deciding on the final one.

You'll know when you have the right Q3 when the sustain & timber sweeps are good.  I made another note on the other BB thread, but it's worth mentioning again: With the original, you'll get a pretty big increase  in volume as the timbre is increased.

http://www.youtube.com/watch?v=pZViQ2H-5s4
[start 1:15]

...I found that adjusting the 10K from the timbre pot can even that out.

btw, what's your Q3C voltage?  I actually got a killer tone at around 1v
edit: (when the balance is full)

[LucifersTrip]

Love that circuit.  Now you gotta try out the Dizzytone.  More hairy.

...yeah, pretty much the same thing...
http://www.luciferstrip.com/fuzz/dizzytone.jpg

I don't know what would make the difference...maybe the 25uF caps instead of 4.7uF....same in/out caps

btw, notice the hfe's (50,50,70). I just checked and on my Buzzaround, I actually used (65,65,76)
http://www.luciferstrip.com/fuzz/buzzaround-final.jpg

[pinkjimiphoton]

fwiw, this is the same schematic i based the "buzztain" on.

lu is right...the right transistor is crucial. get it in there, the whole pedal comes to life and is a really nice fuzz.

the original was a buzz, not a fuzz...much more blatty sounding, and not smooth at all.

nice build, dino!

[digi2t]

I decided to throw together a vero. More compact than what I've seen on the net, left an extra spot open for another clipping diode, and put in reverse voltage protection as well. Seems like I'm on a run of relatively tiny fuzz veros of late  . It's been a welcome change from some of the monsters I've put out before.



I've been leaving out the "standard" 1M pull-down resistor of late. I find that while some circuits need them, other can live without them. I just add it after the fact, if necessary. With the guitar plugged in, the MP20B, at Q3C, I'm getting 1.2v with Balance at max, and Sustain at 0. When I dial up the Sustain to max, I'm reading 0.4v. I did try a 2SB172 (gain 100), and it gave me 1.5v, and 1.2v respectively. An AC128 (gain 97) gave me 1.1v, and 0.25v. Honestly, I didn't hear any appreciative difference between the three. The Timbre control acts as you guys say, but in mine, slightly more distant at minimum, and more "in your face" at max. Maybe I'm not getting the "big" volume difference in mine, because I'm using Q1/Q2's that are a bit hotter at 85/92. Out of the three, I got the biggest difference with the 2SB172. Big, but not enormous. In any case, someone once said, "We're here to please our ears, not our multi-meters.". AFAIC, no reason to put in anything too exotic here, I'll save the 2SB172 and AC128 for something else  . Plenty enough bark, bite, and attitude to go around here.

Oh yeah... when using these "metal-head" Ruskie trannies, make sure they don't touch. The whole casing is part of the BASE, so you'll short the bases together if they do touch.

Cheers,
Dino

[LucifersTrip]

With the guitar plugged in, the MP20B, at Q3C, I'm getting 1.2v with Balance at max, and Sustain at 0. When I dial up the Sustain to max, I'm reading 0.4v. I did try a 2SB172 (gain 100), and it gave me 1.5v, and 1.2v respectively. An AC128 (gain 97) gave me 1.1v, and 0.25v. Honestly, I didn't hear any appreciative difference between the three. The Timbre control acts as you guys say, but in mine, slightly more distant at minimum, and more "in your face" at max. Maybe I'm not getting the "big" volume difference in mine, because I'm using Q1/Q2's that are a bit hotter at 85/92. Out of the three, I got the biggest difference with the 2SB172. Big, but not enormous.

when building this, I went through about 30-40 different transistors and there were very significant differences. I believe it is once again the leakage here that plays a big part. look at Q3...what is biasing it?

the one that killed (2SB376) in my BB is a bit of an oddball in my transistor collection. it is the only one I own with a much longer casing and is odd in the fact that it has relatively high leakage for the modest gain. The one I used had a gain of around 75 with leakage 300uA+, though others in that batch can even leak 500uA-600uA and still have gains <100.  look how long this thing is. you can see it next to the Russian (leakage <50uA), which I used for Q1/Q2. It had to be bent for obvious reasons...


it sounded far better than the rest and if I remember correctly, also gave lower voltages on Q3C...so I was a bit surprised at your .25v and .4v readings, since I believe I took reading with sustain maxed.   btw, this whole thing is a bit funny to me and I'm really happy you got close V readings to what I had, because when I was building this, the people on the thread were shooting for the "standard" 4.5v and I explained reluctantly that I was getting the best sound closer to 1v

with the stock resistors, the timbre gives me a very large difference in volume AND in tonal sweep, from trebly to bassy.  as i wrote earlier, i solved the volume problem with a resistor tweak.

Q1/Q2 is most likely not the reason for the lack of volume change in yours. I did experiment with numerous gains and there was little difference.  I'm guessing it's the almighty leakage...

[digi2t]

Well... after a good nights sleep, and pondering the fact that you guys kept harping on the fact that the Timbre pot was supposed to really give a significant difference when toyed with... I gave it a second gander this morning. Oh my! I do believe I put that 10K resistor off the wrong cap! DOAH!! NOW it's giving me what you guys were telling
me.  Having corrected my error, there was a significant volume boost now with the Timbre cranked, which on the downside made my MP20's sound noisy with the Sustain maxed.

I slapped myself twice... One for Jimi, and one for Lu 

Seriously, I decided to audition more trannies, and I found something fairly surprising (to me anyway!). While some trannies would sweep between Q3C voltages of anywhere between 0.2v and 1.5v (Guitar plugged in, guitar vol. at max, mute strings, Balance at max, turning the Sustain pot from max. to min. Timbre doesn't matter.), I did find some others that stayed fairly steady through the sweep. Some come in at 1.3v to 1.4v, some at 1.2v to 1.3v., and others at 1.1v to 1.5v. They also seem to amplify the least amount of background noise as well, while retaining a really nice roar. I have a choice of denomination to choose from; 2SB172, 2SB176, and MP20B. The 2SB176 seem to be the most consistant, then the 172's, and the MP20's are all over the map. The 172's really shine in the Q1/Q2 spot, while the 176's seem to kick a$$ in Q3. The MP20's on the other hand seem to play best only in Q1/Q2 when using something different in Q3, or in all three slots together.

Another thing, the MP20's having their casing connected to the Base leg, are much more prone to noise pick-up. The SB's are much quieter in comparison.

All that said and done, I've decided to veer away from the MP's, in favor of the SB's. I believe I have my "Holy Trinity" in a pair of 172's in Q1/Q2, and a particularly nice 176 in the Q3 slot. My DMM is giving me gains of 95, 102, and 50. I'm getting the following voltages;
Q1
E - 1.37v
B - 1.47v
C - 4.04v
Q2
E - 1.23v
B - 1.37v
C - 4.04v
Q3
E - 0.4mv
B - 42.0mv
C - 1.47v

And I'm getting this for sound...

It's much brighter, crunchier. Much closer to the Liberal Komrade tone. Thanks for bearing with me guys. Your subtle hints definately helped out here.

One thing though, I will be going back to try the MP20's again, with the 10K resistor the wrong way, it didn't sound half bad. Maybe it just needs a different tone stack? And some decent sheilding.

[glops]

...I found that adjusting the 10K from the timbre pot can even that out.

As per your suggestion in the previous Buzzaround thread, I tried this on two Dizzytone circuit boards that I etched. 
One I used a 47k and the other a 68k.  The 47k has a much better sweep than the 10k, a 33k would be good, too. 
The 68k was too much and killed the sweep.  I am also using a .022uf input cap which works better for my rig.

I have a Buzzaround that I etched from Madbean's PNP, and it's just great.  I threw in some trannies that I ripped out
of a radio and it sounded perfect so I left it as is.  These circuits are fabulous.

Great vid, digi!

[digi2t]

Thanks. No matter how big or small, every circuit is a learning curve. That's the fun.

Another little discovery, the Russian transistors are fizzier on the decay when the Sustain is maxed. No such fizz with the SB's. Most probably due to the casings being such great antennas  . Taking a cue from the Tonebender circuit, I tried a 150pF (didn't have a 220pF) cap between the Q1 C and B. Well golly... 95% of the fizz is gone. Bet a 220pF would be perfect, so I've ordered some silver micas. It's got a roar almost identical to the SB's now. Score one for the Russkie trannies.

Yo Lu! I was just curious as to what your resistor mod was for the Timbre control? I've been thinking about rearranging it to reflect the Tonebender tone control, but I tried it, and I find it changes the character of the circuit too much. Although the tone control works better, it sounds more, muffled, for lack of a better word. I mean, I could live with it as is, but if there is something elegant, that retains the tone, I'll give it a try.

And, this sucker will be getting a volume control for sure. It's so bloody loud  . I have to be able to balance it against other pedals.

[joegagan]

cool thread, love the vids.

[digi2t]

cool thread, love the vids.

Thanks Joe. I love making them, even when I screw up and put the resistor in the wrong place  . Since so many are willing to share with me, it's only fair that I share what I can back. Of course, video is so cool, because the actual sound is there as well. Usually, it so damn hard to quantify, or qualify, something in writing.

I just wish I had the video (and musical) talent of the "Photonic One" though  Yo bro! How's that for a pedal moniker, "Photonic Effects. Sound you can see!".

[LucifersTrip]

Yo Lu! I was just curious as to what your resistor mod was for the Timbre control?

hey..

I wouldn't really call it a mod, just an adjustment....and glops is right in the ballbark to what I got. I actually posted a link to it above,
but here's the pic of my final version w/ voltages



a couple notes...you're not getting a large variety with your different Q3 experiments since, I'm guessing, most of those Japanese ones you used have normal to low leakage. Before you finalize, try some medium & high leak ones there...

...and using those super low leak Russians in the darlington pair will most likely cut back on noise. the 1T308B's I used showed up as zero leakage on the Peak

thanx for keeping a fuzz thread going more than 3 posts!

[pinkjimiphoton]

dino,
if ya haven't boxed it yet, try adding this thing in and see if you like it.

i call it a bias clipper cuz it's kinda what it does.  will let you completely change the contour and sound of the distortion from very buzzy like a bronx cheer buzz, to the jawari thing, and smooth right on up to full tilt fuzz. i used 105k resistors when i built this, and the 220k i specified is really just the two 105k's in series. 10pf on the cap, you can build the whole thing on the back of the pot.

really opens up the sound options of the fuzz. i'd start with the fuzz up full, and the bias clipper off...then slowly turn it up and see what the controls do. the controls  become hyper-interactive with each other, but you can crank it full blast and then just adjust it with the add on circuit alone. it's cool, bro, and if ya don't like it, well, nothing ventured nothing gained.

but i think you'll diggit...:



i used a combo of 1n34 and 1n34a's for the diodes...different kinds of casings.
the 105k EDIT: RESISTOR, NOT CAP goes across the 500k linear pot. the 10p cap goes between pin 3 and wiper of pot, diode clipper connects between wiper and pin 1.
add 220k or thereabouts of resistance from pin 3 of the pot, and hook that to the junction of base and the input cap in parallel on q1.

connect B+ to the wiper. it will let you bend and warp the distortion at will...i think it's a worthy addition.
not sure what it does, but i think it feeds square waves back into it that are heavily clipped and rectified from the diodes, and with the original signal being the source, after being amplified by the transistor...feedback loop or something?
it also seems to brown out the pedal. can get nice pwm kinda fuzz, all the way up to like gary moore kinda ooooooohs. buzz to fuzz. try it, and let me know what ya think.

i'ma gonna go shoot one of dem stupid pedal tricks right now...

[pinkjimiphoton]

dino and brothers...

here's a quick cheezy demo of the bias clipper in this circuit.

sometimes it sounds like it's gargling, it's cool. check it out. you could even put it on a switch!

synthy, mouthy, funky, fuzzy, lo fi, screaming bizzarro octave fuzz and a whole lot more!!!

this is just the pedal, two cords, a cheezy guitar and a cheezy amp!

[LucifersTrip]

it's a great demo...you covered all bases!

[garcho]

Wouldn't y'all rather just fork over 35 grand for a 'real' one?

[digi2t]

Wouldn't y'all rather just fork over 35 grand for a 'real' one?

I pity the poor sap that would pay that, or anything even remotely close to that. By remotely close, I mean, take off a zero... or two.

[LucifersTrip]

....and there's no sound file and you have 3 days to pay with no returns. It's also tough to trust somebody that is selling a 35K item and can't write a proper sentence.

"And more important its owned by celebrity that everyone's know!!"

[pinkjimiphoton]

cool thread, love the vids.

Thanks Joe. I love making them, even when I screw up and put the resistor in the wrong place  . Since so many are willing to share with me, it's only fair that I share what I can back. Of course, video is so cool, because the actual sound is there as well. Usually, it so damn hard to quantify, or qualify, something in writing.

I just wish I had the video (and musical) talent of the "Photonic One" though  Yo bro! How's that for a pedal moniker, "Photonic Effects. Sound you can see!".

lmao...nice, bro!!!! btw, the mp16b's can't touch, either. same thing, shorts out.