univox superfuzz transistors-chasing my "longtail"----help!

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univox superfuzz transistors-chasing my "longtail"----help!

fuzznaught
hello, so I have it all built up and am measuring Q's for the sockets. I have read in the comments about low Hfe's being best, the lowest I can find being 2n2222's all within 185-220 Hfe, hopefully that's not too high still, but I saw someone say they gave it FuManchu sound (which is exactly what Im after)... Mainly Im trying to find out which is the "long tailed" pair that is crucial for them to be matched exactly. I can't seem to find a definative answer via google, so is Q4 & Q5 the pair referred to as "long tailed"?? Also, I saw pinkster's values posted for Hfe's he used, but I dont have a Q remotely close to 55-60, should I still put the highest Hfe in the Q1 slot? Any transistor advice is appreciated immensely, not really looking forward to a day of swapping transistors, (Im already doing that w/the diodes) THANKS!
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Re: univox superfuzz transistors-chasing my "longtail"----help!

fuzznaught
Plenty of views, but no reply. I see I'm not the only one that doesn't know what "long tailed pair" means, haha...j/k. A lil update: spent today swappin transistors and it still isnt superfuzzy. There isnt alot of audible difference really no matter where I put which one. Ive matched the Q4/Q5 anyways (at 200 hfe), put the lowest i have (90 hfe) in Q6, and the highest in Q1. When on the octave setting, it sounds ok maybe, I think. But on the scooped setting (the one I want to use 99% of the time) the sound is more clean guitar tone with fuzz mixed in a little in the background. The fuzz I can hear sounds awesome, but it's very faint, with the clean tone alot louder. Ive swapped diodes around as well, but that didnt help. Im gonna take a stab at the superfuzz posted on FSB next because it has some trimpots on the layout, and I was thinking it might be able to be adjusted or dialed in? Maybe someone knows if I can add the same trimpots to the layout from here? Or if that would even solve the issue? Are there any resistors that could be changed to make it more of the fuzz sound? Any help is much appreciated, thanks!
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Re: univox superfuzz transistors-chasing my "longtail"----help!

Beaker
http://www.aikenamps.com/LongTailPairDesign.htm

This is a typical drawing for a "long-tailed pair" - so look on the shematic and find a similar component layout:

http://www.univox.org/pics/schematics/superfuzz.gif

As you can see they are the ones 4th and 5th from the left, just before the diodes.

Now look at the bases of Q4 and Q5 - see they both have a 22k resistor coming from them.

Now look at the Tagboard Vero layout:

http://3.bp.blogspot.com/-gLy8HWE7qQs/TyBDc5__vMI/AAAAAAAAAcg/HiPt_bZl5-w/s1600/Univox+Super-Fuzz.png

Find the Transistors that have 22k resistor coming from the base - by my reckoning it's Q1 and Q4.

Therefore for THIS layout, the long-tailed pair are Q1 and Q4.

Hope this helps.
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Re: univox superfuzz transistors-chasing my "longtail"----help!

fuzznaught
You are awesome Beaker!!! Thanks man. You've really helped more than just with this particular issue. Altho I won't get a chance to try it with matched Q's in sockets 1&4 until this eve, can't wait. Im also going to try to find out if I can add any trimpots to this layout to see if I can dial it in any better. Especially now that you got me to figure out what a few of the symbols in schematics mean, they don't seem so intimidating. Being a total novice to all of this, Ive ran from anything with a schematic. But now that I know what some of the basic symbols mean, Ive been way more interested in learning how to decipher them. Ive been on the beavis site for a coupla hours now and can't believe I'm actually starting to understand schematics. Its sorta like "give a man a fish and he can complete his pedal, but teach a man to fish and he can build all sorts of cool stuff", haha! But seriously tho, thanks for the kick in the pants, I feel like I'm really learning a generally useful skill. I appreciate it. 8)
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Re: univox superfuzz transistors-chasing my "longtail"----help!

Beaker
This post was updated on .
No problem at all, and I'm glad I could help out.

I've built a couple of these myself, on PCB that a workmate made for me - (I work in a college).

You REALLY do need a schematic whenever possible, to go along with your layout. It will make life SO much easier if you run into problems like this.

In terms of electronic knowledge I am a charlatan really - I know what I am doing, and how to do it, sometimes know why I'm doing it, but rarely understand why, so I am in awe of some of the guys on here.
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Re: univox superfuzz transistors-chasing my "longtail"----help!

fuzznaught
I think "charlatan" mite be being a bit modest...Im sure the schematic does come in handy when building from a layout, but when it just looks like ancient hyrogliphics, its less helpful than a cookie recipe :) I want to know everything right now dammit. LOL. But thnks to you, I at least know how to spot caps/resistors/diodes on one now, almost. Anyways, I fiddled with the Q's again for about an hour, matched 1&4 and its still more clean tone than fuzz. Ive spent hours upon hours swapping transistors and Im probably gonna have to replace a couple of sockets soon here if I don't accept it is what it is. Im thinking thats why the other layouts have trimpots maybe. I still can't figure out how to add trimpots to the layout I built, or even know if that would fix the problem. And of course I find a layout complete with trimpots just after finishing this one :doh  ...Luckily I have alot of 10u caps...haha.
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Re: univox superfuzz transistors-chasing my "longtail"----help!

Beaker
This post was updated on .
The thing I love  the most about this site is that you can REALLY trust the layouts posted - if it says verified then it works - no arguement. Before finding this site I have tried layouts from loads of other sources and some of them are just plain wrong, so be warned, you might be onto a winner you might not.

The trimpot on some layouts, including the PCB build I use, is only there to fine tune the amount of octave effect, so something is definitely wrong with your build as this thing is as fuzzy as they come. The "Fuzz" knob is not "less fuzz/more fuzz", instead it alters the character of the fuzz tone, so even full counter clockwise it's Chainsawsville Arkansas.

Before you decide to start again from scratch with another layout, check EVERYTHING again - links, cuts, component placement, component value, polarity, and soldering for bad joints or short circuits. Then check your offboard wiring. Also have you got a dodgy component somewhere?

I suffer from what I call "solder blindness", others probably do too: I can look at a malfunctioning board over and over again, and find nothing wrong. However if I put it aside for a few day and forget about it, then take another look, I can usually find the fault in seconds - somehow the (for example,) misplaced resistor just jumps out at me, when a few days before I could check it ten times over, and be convinced it was in the right place.

If all else fails though and it just won't work, often it's best to start again from scratch. Frustrating yes, but at least it's improving your skills all the time. And you know this layout works.
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Re: univox superfuzz transistors-chasing my "longtail"----help!

fuzznaught
dude you hit the nail on the head there. I need to quit looking at it for awhile. spent so long swapping transistors, I was starting to put em in backwards. I couldnt say if its the build or not cuz I dont have anything else to compare to other than utube vids. It sounds exact on the octave setting. But on the scooped it just seems like the ones in vids have just a wee bit more of the fuzzy part of the tone in them. The only reason I was thinking it just needed to be "tweaked" a lil is cuz Ive read about ppl using different resistor values or trimpots to sort of dial them in. It seems sooo close to what other ppl's sound like, which is making me think the build is ok. They all seem like I can kinda hear the basis of the "clean" signal within the layers of sound, mine just seems like that part of the signal is a little louder? maybe? I could just be trippin cuz Ive been messin with it too long. I was thinkin I just need to build like six of em&pick the best one. And yea, I was weary as hell of a layout not being from this site, but I asked the guy a couple questions on it (derringer on the FSB site) and he replied rite back, super helpful, and there's quite a few others that seem to be lovin it. But it would be my first build that isn't from this site, just the diff color of the strips scare me, lol. I was a serial lurker here and other vero sites, but this forum's the first forum Ive ever actually registered and made a post in. Not only are the layouts here the easiest and most reliable anywhere Ive seen, but the the M's (mark&miro) are so flippin fast to reply to a question/problem, they are what I refer to as "the L.O.VE" (the Legends Of Vero) haha. Thanks again for the help too man, Im def gonna shelf it for a day :)
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