Univox Super Fuzz questions

[Heemis]

I'm planning to build a univox super fuzz using this schematic:

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

I noticed the thing is chock full of 10uf electrolytics.  They appear to simply be dc blocking caps between sections, and I'm assuming it would be fine to use 1uf film caps in these spots without effecting the unit's operation, is this correct?

Also, I was planning on ordering 6 2sc828 transistors from small bear, but they're fairly expensive... is there any reason why I can't simply use 2n3904, or 2n5088s for this?  Does someone have a recommended hfe for each of the transistors in the circuit?

Thanks in advance!

[GREEN FUZ]

From what I remember, the original transistors were fairly generic and don`t contribute much to the sound. I used 2N3904`s in mine.

Can`t remember specific hfe`s off the top of my head but there are a ton of threads relating to it*. As for the caps? I don`t know.





*Here`s one
http://www.diystompboxes.com/smfforum/index.php?topic=69393.0

[Heemis]

Thanks for the reply!  So it looks like any transistor with hfe of about 200-300 is good for this circuit.

Anyone have any info on the caps?  I have an abundance of 1uf electro and film that I'm assuming will be fine.  Can anyone confirm?

[isildur100]

I remember experimenting on the breadboard with different transistors and they do not all sound the same, even if in the 200-300 range. I tried 2sc828, bc549, bc109 and 2sc1815. For me the best sound was a combination of 2sc1815 and 2sc828. I found that using only 2sc828 made the sound a little muddier.

As for the 10uf caps, I tried  other values and also using tantalums and the best sound was with 10uf. You should build this on the breadboard and try different options. Its a fun circuit to play with.

cheers

[Mark Hammer]

+1 on the non-criticality of transistors.  The only place where you might consider being fussy is on the mirror pair used to generate the octave-up.  If you are able to measure it, try to find a pair with roughly equal hfe.  So, something like 234 and 238, rather than 232 and 267.  There IS the 10k trimpot for achieving better balance and octaving, but its easier to simply start with two trannies that do roughly the same thing.

The diode pair closest to the output side is not really necessary, or can even be altered.  I have a Si/Ge/nothing switch in mine.  As well, the midscoop filter can be reduced in effect by inserting a small resistance between the 1uf cap and ground.  A 5k pot or even a 2k pot will serve to retain more mids, and a "throatier" sound.

[slacker]

I built mine with mostly 1uF caps simply because that's what i had lying around and it sounds great, I don't think the values are that important.

[Heemis]

Thanks for the input everyone.  Looks like I pretty much have everything I need to throw one of these together.  Now if only there was a readily available comparable enclosure...