DIYstompboxes.com

DIY Stompboxes => Building your own stompbox => Topic started by: jrc4558 on March 04, 2004, 03:15:02 PM

Title: Quietest silicone transistor
Post by: jrc4558 on March 04, 2004, 03:15:02 PM
What would be the quietest silicone transistor, n-p-n, to use in a fuzz face type cirquit?
Title: Quietest silicone transistor
Post by: The Tone God on March 04, 2004, 03:41:37 PM
I think you mean silicon unless your trying to make a fuzz out of breast implant although that would be cool but I would get rid of the fuzz part. ;)

Andrew

P.S. I'm a silly mood again.
Title: Quietest silicone transistor
Post by: smoguzbenjamin on March 04, 2004, 03:42:12 PM
Wow. Fuzzy boobs 8)
Title: All kidding aside...
Post by: David on March 04, 2004, 04:05:35 PM
I've heard that the 2N5089 would fit that bill...
Title: Quietest silicone transistor
Post by: Triffid on March 04, 2004, 04:38:15 PM
Doesn't the 2N5089 have too high of gain for a fuzz face?
Title: Quietest silicone transistor
Post by: RDV on March 04, 2004, 04:47:08 PM
Quote from: TriffidDoesn't the 2N5089 have too high of gain for a fuzz face?
I've used 2N5089 for Q2 & 2N4401 or 2N2222 for Q1 with very good results. That low gain stuff seems to matter more with Ge FFs.

Just an Opinion

RDV
Title: k
Post by: petemoore on March 04, 2004, 04:53:25 PM
With biasing a transistor can be made completely silent. Disconnecting the collector from the circuit will yield similar results
 Using fancy low tolerance resistors is said to lower bias noise.
 Large resistors may make noise too sometimes.
 Mosfets run real quiet, but I never had luck with those in FF Q1.
Title: Quietest silicone transistor
Post by: nightingale on March 04, 2004, 05:26:17 PM
hello~
i would just steer clear of the 2n2222's... in my experience they are pretty noisy... plastic, or tin can..

as suggested by gus, the 2n4401's are pretty good for SI, FF's... i also built a YAFF with them and it was great.. had loads of fuzz for a FF type circuit..
hth,
Title: Quietest silicone transistor
Post by: R.G. on March 04, 2004, 05:26:34 PM
The MPS A18 has the lowest noise figure of any US made device for the audio range that I've seen. However, it's not all that good for FF circuit.

There may be some Euro or Japanese devices with better characteristics for this.
Title: Quietest silicone transistor
Post by: brett on March 04, 2004, 07:21:53 PM
In Si Fuzzfaces, there's a relationship between gain on Q1 and noise.  You can lower the gain (and noise) from Q1 by putting a small (e.g. 22 ohm) resistor on the emitter, or by reducing the 33k resistor on the collector. (I've tried everything from 10k to 150k on the collector of Q1 and 33k is a good compromise for gain and noise, but from memory lower values were quieter).

As RG said, MPSA18s are very quite.  2N5089s are quiet, too.  Their problems are high gain.  Therefore, it might be worth trying them, but with a small value emitter resistor.  Just a guess, really, but might work well. :?:  

cheers
Title: Quietest silicone transistor
Post by: Zito on March 04, 2004, 09:28:25 PM
Wow. Fuzzy boobs

I wonder if it would be like an old car radio!

Push one in Fuzz On, Push the other one in Fuzz Off.

Now that's a reason to play bare foot.
Title: Quietest silicone transistor
Post by: jrc4558 on March 05, 2004, 01:40:25 AM
OK, here we are. I tried Jack Ormans Mos-Face. All the 2nxxxx stuff hisses like a preying snake. However!!!
If you use a BC547b for Q1 and drop the collector res to 51k - she's quiet.
Not idealy quiet, but better that with say a 2n2222.

Any ideas on how to make it more quiet? I want silence between notes, while there's still a conciderable amount of hiss.

Thank you all.

PS. And yes, fuzzy boobs...  :twisted:
Title: Quietest silicone transistor
Post by: Aharon on March 05, 2004, 09:00:22 AM
Did anybody try the 2N2369 when building a YAFF?
Aharon
Title: Quietest silicone transistor
Post by: Triffid on March 05, 2004, 09:26:02 AM
I built a Silicon Fuzz Face with BC108's and it is quite as can be.  Here is the thing though...

1. It wasn't quite until I put it in it's aluminum house
2. It got much better when I added input and output pulldown resistors
3. I can quite it up even more with the bias (50K input) pot that I added

Hope this helps
Title: Quietest silicone transistor
Post by: jrc4558 on March 05, 2004, 11:14:38 AM
Thank you!
Title: Quietest silicone transistor
Post by: jrc4558 on March 05, 2004, 11:15:12 AM
Thank you!
Title: Quietest silicone transistor
Post by: nightingale on March 05, 2004, 03:32:35 PM
ahron~
i built my 1st yaff with the  2N2369.. and it sounded really good. the ones i found had the big tin can package.. the fuzz was very touch sensetive, and "spongy" sounding...
only problem that it was barely louder than unity when switched on, but at that time i was playing it full time.. using the volume to clean/saturate my tones...
hth,
Title: Quietest silicone transistor
Post by: Aharon on March 05, 2004, 03:51:22 PM
Hi Nightingale.
Those tin can ones are the ones I got.
The other ones are MPS2369 I believe.
The cure for your problem is to add another stage,for example,put your MosBooster after the YAFF.
I call it the YADDA(YetAnotherDistortionDerivativeAgain!)
Aharon