DIYstompboxes.com

DIY Stompboxes => Building your own stompbox => Topic started by: superferrite on January 24, 2008, 01:26:26 AM

Title: Fuzzrite fans: Transistor selection choices?
Post by: superferrite on January 24, 2008, 01:26:26 AM
I found Dragonfly's Fuzzrite vero layout and I'm going for it  for build #3!

What transistors should I try?  Which resistors should I try to bias it correctly?  Does it matter?!?

Thanks youse guys!
Title: Re: Fuzzrite fans: Transistor selection choices?
Post by: superferrite on January 25, 2008, 03:17:12 PM
Bump!
Nobody loves Iron Butterfly?!? ; )
Title: Re: Fuzzrite fans: Transistor selection choices?
Post by: Dragonfly on January 25, 2008, 04:13:01 PM
Sorry...I didnt see this.

I typically like lower gain silicons (depending on the fuzzrite version...theres a silicon and a germanium version in my gallery) like 2N3903's, and there are a BUNCH of cool NOS transistors, if you have access to that stuff...otherwise 2N3903's are fine...even 2N3904's are good. I would avoid using any transistor with an hfe above 250, and would really recommend anything in the 100-200 range. I havent tried 2N4401's, but those might work...as well as 2N2222's.

I hope this helps.


Andy

PS...there are a bunch of threads on the Fuzzrite...search the forum and I bet it will give you all kinds of new ideas !
Title: Re: Fuzzrite fans: Transistor selection choices?
Post by: superferrite on January 26, 2008, 01:01:07 AM
right on!

I saw the recomendations for 10k resistors vs the 370k ones--I'd assume this is for the 100-200 hFe trannies, right?
Thanks for the nifty, neat, and elegant layouts on your gallery!
Title: Re: Fuzzrite fans: Transistor selection choices?
Post by: albertozioli on December 14, 2010, 09:03:45 PM
Guys I'm trying for ages build my fuzzrite clone and I have some problems, could you guys give me a hand, I'm talking to other guy on the mosrite forum, he is tring to help me as well, this is the link has some pictures of the project there...

http://www.mosriteforum.com/forum/viewtopic.php?f=20&t=3807

Cheers!
Albert
Title: Re: Fuzzrite fans: Transistor selection choices?
Post by: LucifersTrip on December 15, 2010, 01:43:05 AM
Quote from: superferrite on January 24, 2008, 01:26:26 AM
I found Dragonfly's Fuzzrite vero layout and I'm going for it  for build #3!

What transistors should I try?  Which resistors should I try to bias it correctly?  Does it matter?!?

Thanks youse guys!

I had excellent luck with these 1.9 cent transistors:
http://www.taydaelectronics.com/servlet/the-1741/2SC1815-TRANSISTOR-NPN-50V/Detail

I believe the hfe was ~ 120-160

good luck
Title: Re: Fuzzrite fans: Transistor selection choices?
Post by: petemoore on December 15, 2010, 06:11:22 AM
  470k seemed huge for collector resistors, I paralleled smaller resistors across them, this reduced the gating effect I was experiencing. Lowish Hfe seems reasonable to suggest since the bias is 'squashed down' by the large C resistors.
  Perhaps the large collector resistors keep the out of phase AC output/draw of the transistors a bit more independant from the power supply/each other ?
Title: Re: Fuzzrite fans: Transistor selection choices?
Post by: deadastronaut on December 15, 2010, 06:48:12 AM
Quote from: petemoore on December 15, 2010, 06:11:22 AM
  470k seemed huge for collector resistors, I paralleled smaller resistors across them, this reduced the gating effect I was experiencing. Lowish Hfe seems reasonable to suggest since the bias is 'squashed down' by the large C resistors.
  Perhaps the large collector resistors keep the out of phase AC output/draw of the transistors a bit more independant from the power supply/each other ?

hi pete, just wondering, what is the most sustainy with a bite, but not harsh.. of all the plethora of fuzz's...any recommendations?

cheers rob.
Title: Re: Fuzzrite fans: Transistor selection choices?
Post by: Mark Hammer on December 15, 2010, 09:52:54 AM
The one that has the most boosted signal fed to it.

In many respects, the signal does not care where the gain is applied.  You can insert the gain into the fuzz itself to get the needed level, or you can have the gain precede the fuzz, and make do with whatever gain is part of the stock fuzz design.  Six of one, half dozen of the other.  EVERY fuzz is capable of sounding simply awful with the wrong signal fed to it, and glorious with the right one.