How Important Is Having A Well Balanced Pot For A LarMar?

[rp]

As I need to source one for my Rocket. I just noticed on the posts it seems to matter much to some, but my PI tube isn't checked for balanced so I'm not sure why it's critical for some. I'm fine with splurging ~$20 for an Alps Blue but if I can can use $3 Alpha and it's no big matter I'll do that. I might sell the amp so I should consider containing costs.

[Reeltarded]

If it is off by more than 10% through the range I moved to another. I have installed only 2. Those were not matched perfectly either, both Alpha.

[rp]

10% is a lot in 2013, I hope the Alpha QC isn't that bad. So what's the effect of the tracking being off by more than 10%, what'll you hear, real or theoretical?

[Reeltarded]

With imbalance built in at the PI, and tolerance of most components around there at 10-20% I figured there was a 50% chance that the lowest side would end up controling the lowest side around 4-7ish. I had five to choose from. Two were very close, one was pretty close and the others were near enough to each other at the ends of travel but not so much on the middle.

No other reason.

I like Alphas though. I have never experienced a failure that I can remember, and their 500ks are lovely as guitar controls.. ehh..

[martin manning]

You'll get unequal drive signal, but an unmatched PI tube will do the same thing. Unbalanced means second harmonic distortionso maybe it will sound better, or maybe you won't be able to tell. A simple experiment could be done to see.

[rp]

hmm, for the price of a Blue Beauty I could get like 5 Alphas.

I like Alphas too, and best feel out there considering the cheap price. If they tripled the price people would appreciate them more.

[Diablo1]

Use a linear dual gang pot instead of an audio taper pot. Linears are much more accurate. If you like to tinker, you can tweak the outputs for even better balance with a couple of precision resistors in parallel.

[Gaz]

I like a linear pot better anyway, like the original Ken Fischer mod. Volume comes on way too slow for me with the audio taper. I like to have a finer sweep in the louder stage volume area, so I can just take down the volume a hair at a time. Better balance is also a bonus, but I have never worried about it for the aforementioned reasons.

[Diablo1]

I just received and checked ten Alpha 250-K linear dual ganged pots. I've got three that match within 1%. The rest are about 10% off over the entire sweep of the pots.

[Gaz]

You can compensate for the difference with a linear pot by using different value 'safety' resistors. This is a bit annoying if you don't have a lot of resistor values on hand though.