Hello to all,

I am trying to find high quality CARBON potentiometers (linear) for a tube preamp (guitar preamp).

Currently I use Omeg pots (www.omeg.com), which overall are great-
but are made from polymer plastic and that affects the sound in a non-desirable way (they somehow sound sterile, "dry").

I noticed that carbon pots (even cheap ones) sound more natural, closer to a "vintage guitar amp sound" I am pursuing..But -especially when their price is low-their quality is not good, they produce noise after a month of operation..plus their resistance values may vary a lot etc etc (common carbon pot problems).

I need to find myself a company that produces HIGH QUALITY carbon pots, something that costs but endures heavy usage and has very low noise.

The values I need are 4.7K , 10K , 1M , 2.2M (all linear)
Also, I will install on them "push on" knobs, so the pot's "neck" must be appropriate.

I am willing of course to buy in quantity, not just a few of them.

I could try the "Honeywell Clarostat" pots, but I think they don't have some of the values I am asking.
Is anybody familiar of a similar solution?

Also, the shipment location would be Europe.

Any suggestions?

Thanks in advance for the help.

xmat.

 

I don't understand that.

This sounds like one of these physiological things.

Do you prefer valve/tube amplifiers?

Do you think vinyl sounds better than a CD?

Those polymer pots are lower noise and higher quality than carbon, I don't see the problem.

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Those polymer plastic pots sounds clearer, with less noise indeed.

But, when actually playing guitar through a tube preamp with Omeg pots (or plastic polymer pots in general),
the guitar "feels" a little "stiff" on the hands..sounds unnatural, plastic.

So, what I am trying to find are carbon potentiometers that may cost 3-5 times the price of Omeg pots and have the some low noise behavior (well I can settle with a little bit more noise than that!).

Good candidates are Alpha pots (they don't have 2.2M value and I'd like more quality),
or Clarostat pots (don't have the 2.2M value but very good in quality),
or even PEC ones (never test them myself)...
Sadly I don't know from where to order the last two brands..I am located in Europe.
Is there anybody here that can provide such info?

BTW, of course I think valve amplifiers sound better, but only when it comes to applications like guitar amplifiers..actually I think most guitar players feel the same way.

Thanx for the tips.

 

Here is a company that might be of help.
http://www.precisionelectronics.com/...s,%20Specs.htm

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Ok thanks I 'll take a look!

xmat

 

If you want the special carbon pot sound, be careful. Avoid those that are too good.

 

I would bet dollars to donuts you wouldn't be able to hear the difference in a blind test.

Carbon comp stuff has a bad voltage coefficient of resistance, bad enough to result in greater than 1% THD, but it has to be in a real high voltage stage of the amp for it to have that effect.

Conductive plastic and cermet are much better pots.

 

He doesn't want the sound to be clear. He likes and wants the distortion made by a lousy old carbon pot.

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Uncle $crooge

 

Oh really? Why is that? If you have an experience you can share with me, it'd be really useful.

In reply to the guy saying there is no noticeable difference between carbon and polymer pots,
I must admit it's something you mostly feel in the amp's response when you play guitar and certainly not something everybody can hear.

Some guitar amps are actually built to be susceptible to noise and/or produce noise artifacts, especially when the amp is used on distortion/overdrive mode..
This tends to be one of the trade-offs a guitar amp has to suffer from to be able to "scream",to produce "musical feedback" and characteristic "voicing".(sometimes, not a general rule)
So, yes I need some of the carbon pot noise..but certainly not the one cheap carbon pots have.

I also need something that has a very long life (at least 30000 turns), cheap carbon pots can't offer that.

BTW, I contacted the Canada company currently waiting for their response.

Thanks for the help guys, it's invaluable.

xmat

 

Geetar amps have terrible and distorted old fashioned circuitry.
The ones that are susceptible to noise have a peak in their high mid-range frequencies because the amp does not have a flat frequency response.
"Screaming" is just severe distortion when a circuit is over-driven.

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Uncle $crooge

 

I would be very interested to know the results of a double-blind test done using both kinds of pots. The problem with normal "playing and listening tests" is that the user (player) already knows what they're using, and their impression will be impacted accordingly.

I've noted that with one recording (done to tape) which I played on, people say that the audio sounds better and more natural than others I've played on using Pro-Tools (or RADAR). The problem is that this recording was done to ADAT, not analog tape.


Torben

 

I would suggest the only difference 'may' be in the mechanical feel of the pot, I doubt any pot sounds any different, particularly in a valve guitar amp with it's very low quality.

My daughter did her OCN Sound Engineering course using ADAT (they had three to give 24 channels), but they have since moved to HDD recording, and now (having changed venues) they are using computer recording instead.

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