[enemigo]

I am using the Alps (50mW Carbon Control Potentiometers, Log, 10k. RS-Components# 249-9159) for my amps. I'm listening to two different ones now. One seems to have higher level on the left channel when turned to almost maximum resistance, the other pot seems to have higher level on the right channel. When I turn up the volume, the channel levels even out for both amps. Both amps got gain of 10-11, so I can't turn my pots up much with lowZ cans. Is this a tolerance problem with the Alps, or am I causing this by a bad solder joint or such?

Knut

 

[morsel]

Poor left/right channel tracking is a common problem with cheap pots. That's why people pay premium prices for Alps RK27, Noble AP25, or stepped attenuators.

 

[enemigo]

Thanks.

The Alps RK27 (STRK27101 - 10k log) sure was "premium priced", equivalent to almost $40 from RS Components Norway!!

How about the Vishay-Sfernice (10k) reccomended in the cmoy article at tangentsoft.net? It is better priced, but still fairly steep at almost $30.

Any other, cheaper pots I should consider? I'm fitting it in a mint sized amp, so size is of importance.

Knut

 

[aeriyn]

Quote:

Originally Posted by enemigo Any other, cheaper pots I should consider? I'm fitting it in a mint sized amp, so size is of importance.

Panasonic's EVJ log curve pot is a good inexpensive pot. Not nearly as sexy as an ALPS RK27, but it is pretty small and will fit in mint-tin sized amps. Digikey carries them but I don't know how you'd go about getting them outside the USA.

Edit: The pana EVJ does have tracking issues at very low volumes (remembering from the last amp I had that used it) but lowering your gain to allow you to use more of the pot's range would probably be advisable.

My PIMETA has a gain of 3 and I still only use the bottom 1/3rd of my ALPS RK27 pot. Thankfully the RK27 doesn't have major tracking issues at any volume, but it's not really an option for portable amps due to its large size (it's nearly a 25mm cube).