# 2N2222 PN2222 and noise hiss zener issues



## keeperofthegood (Apr 30, 2008)

Hey oh

I'm hobbled for the time being with limited net access so felt like asking here rather than trying to google ellusive traces of information. I recall reading on various forums comments along the linens "the xN2222/x is known for noise" and that they are fine when noise or hiss is not an issue. I have a box of various low power transistors including both the 2N and PN 2222 animals with various fuzz intentions for their use so for me the noise is not an issue. However, in talking about this with a friend he said "since when are they noisy?" but my google as I said is limited at this time. So hoping that someone here has an idea where to look that explains how these transistors could/would be noisy/hissy.


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## keto (May 23, 2006)

I've used them a fair bit and not found that. What I have found is that they vary in sound rather dramatically from batch to batch - I have 3 different kinds here and they all have distinctly different sonic qualities used in fuzzes, but hiss and noise isn't particularly one of them. Actually I have some 2N2222 (2 kinds) and some 2N2222A (3 kinds), which are higher gain. I find the basic 2N2222 to be pretty uninspiring, and of the 'A's, the first batch I bought are easily the best and and I can't find more of them 

They're not a zener (at least as far as I know), not sure why that is in your title.


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## mhammer (Nov 30, 2007)

1) Some transistors ARE intrinsically lower noise than others, and are selected as such for high end audio applications, but the noise you hear is nearly always a product of the entire configuration, rather than the transistor per se. The same is true with op-amps. Some op-amps that kick the ass of another kind under one set of circumstances get their own ass kicked under a different set of circumstances, and the same is probably true of trannies.

2) Earlier this year I bought myself an old Heath guitar amp. It uses 2N3391 transistors in the preamp section. These are not known as being either noisy or quiet. I was rather dismayed by the constant hiss. I had bought the amp because a buddy in high school had built one and I was always envious of him. This did not seem to live up to my memories at all. Then I read somewhere about transistors suffering the effects of time and use (what!!??) and how one owner of this amp had cured their hiss issues by simply replacing the 2N3391s. I did the same, using the fairly generic (and not identified as low-noise) 2N5088, and the hiss went bye-bye.

Is it possible that some sort of mythology has emerged about 2N2222s being hissy? Possibly. But then, these babies have been around for a *long* time (easily 45 years), and are about as generic a small-signal transistor as the equally ubiquitous 2N3904. As with a lot of these thngs, people either fail to consider, or fail to document or articulate the circumstances under which a given component was found to be less than ideal, and people just start accepting that the component is problematic under ANY circumstances.

3) Its a *fuzz*, for crying out loud. The amount of hiss generated by taking your guitar signal and applying gobs of gain to it to produce distortion will exceed whatever the transistor itself inserts. It's a bit like the way people used to think eggs had all this cholesterol, conveniently neglecting the fact that they fried them up and ate them with bacon and cheese and served them with buttered toast. The eggs were NOT the culprit. Similarly, if a Univox Superfuzz or fender Blender used a half dozen or so of them and was a hissy effect, it wasn't because they used 2N2222s.


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## keeperofthegood (Apr 30, 2008)

thank you Keto and Mark. Yes, for me it wont matter a hill of beans. My friend is building himself a TV transmitter 'super simple' style and that is where the topic of noise in the system arose. Yes, myth does become a way of life at times so I am glad I asked about this.

Keto, if you reverse bias the base-emitter you get breakdowns including zener. Nice bit of long posting on that facet is http://www.edaboard.co.uk/2n2222-zener-noise-t486829.html full of the typical 'im smarter than your drivel' comments of course but in general it does give some interesting information to follow. So, in that consideration I put the zener in the title incase what was floating about really was more that effect than the 'proper' function of the transistor.


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## GuitarsCanada (Dec 30, 2005)

Welcome back Keeps


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## keeperofthegood (Apr 30, 2008)

GuitarsCanada said:


> Welcome back Keeps


Thank you Scott!! Been too long, or at least feels like too long. Just lucked into the ability to get this thing today from Tiger Direct. Not a Ferrari by any standard, more like a Geo  but it will get the job done for me!


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