Great Cheddar Noise

[mcwilson]

Quick question on the Great Cheddar. I got mine working no problems and it sounds great. My only issue with it is that it is a little bit noisy. It isn't too noticable when playing and the noise is gone in bypass. I would compare the hiss to be similar to my Japanese PH-1. Is this normal? I know it is a dirt box so it might just be how it is.

Thanks

[Bernardduur]

I have absolutely NO hiss with this pedal.

What kind of transistor do you use? Checked the voltages?

[mcwilson]

I haven't checked voltages yet. I used the transistors of the same type listed in the parts list from small bear.

[Gus]

Like posted above the effect should not have a lot of hiss. 

I have bought NEW transistors and the ones I tried in a bag of 100 have to much noise.

  It is not just the number but sometimes the brand or batch of transistors. 

I would try other transistors.  FWIW the way that circuit is designed most any small signal Si transistor should work.

Did you overheat them?  I would guess the transistors you bought from SB were good

[mcwilson]

Yeah, I am just not sure of the brand. I will measure the voltages when I get home. I will also try it out with a battery and see if that is the problem.

[R.G.]

A bipolar transistor has its noise performance degraded if its base-emitter juncion is reverse-zenered **even once**.  The amount of damage is cumulative with how much current passes through the junction in reverse breakover. Many spikes give a little worse each time.  High reverse current once is a lot of damage.

This applies even if the transistor was once immaculately low noise.

[Bernardduur]

If you are replacing the trannies, also check other transistors. I love the pedal filled with BC140 or BC141 (Hfe 100) transistors. Also, a great mod is to add a switch to remove the transistor / diode to ground.