Potentiometer's effect on signal purity

How much effect can a potentiometer of a given quality really have on the signal?
I know that technically, if I turn the pot to max, it is less an intrusive part of the circuit and the signal should pass it preferably unimpeded. There are many who claim that yes, a high quality pot will give better sound and won’t cause unnecessary harm at any turn.
My Electrocompaniet integrated’s pot causes some shizzling when it’s adjusted. Should I replace it?
Actually I feel that I do get softer, better sound with the pot maxed and DAC attenuated lower (just below the amp’s input sensitivity, of course), there’s just the problem of increased hum probably due to my AC quality. Or maybe the amp needs some replacing of caps, etc… Or maybe its transformers have suffered from shorts. Dunno.

I’m not, like, neurotic about the potentiometer but if it’s fact that a premium pot will improve the signal and not marginally, I’ll buy one.

Is it pcb mounted or hand wired?
I’d expect it to have a quality pot anyway, but if not you could always swap it for an ALPS “blue beauty” not too expensive and a good reputation (and feel).
Me I like my power amps that have a level control as well, very useful!

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That’s PCB-mounted right. Well of course it is.
What a hassle to replace… How do I get under there?

If the potentiometer is making a bit of noise when adjusted, that’s typically a symptom of needing to be cleaned. Looking at your PCB, leave well enough alone unless you’re prepared for major disassembly to get to the solder pads on the backside. Invest in a spray can of contact cleaner. It should come with a nozzle to direct it right to the spot you need it. You don’t need to disassemble or otherwise disturb anything. You can let wicking action do the job with a couple of squirts into the front of the potentiometer where the shaft is (yes, you can do it even with it connected to the extension shaft to the front panel). Give it a bit of time to penetrate and repeatedly rotate the potentiometer through its’ full range to let the wiper, combined with the contact cleaner, do the job of clearing the contact surface. Do this with 2 or 3 applications of the contact cleaner. That’s what I would do.

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Thank you kindly.

Other than that, have any of you guys “listened” to different potentiometers?
I’m somehow really interested in dedications to discretely listening to selected parts in the signal path, listening to and swapping capacitors, pots, what have you. I don’t have money to do this, but like reading about it.

It also depends on the topology of the potentiometer.

Analog potentiometers come in 3 dominate topologies and each effects the impedance differently down stream. The 3 types are Shunt, Series, and Ladder.

Series - Series of resistors forming one long voltage divider, and input impedance remains constant, however signal has to run through a series of multiple resisters unless volume is 100%. Mechanical sweeper volume controls are this type.

Shunt - Inexpensive, signal flows through only 2 resistors; but the signal source see a variable impedance.

Ladder - Most expensive to implement, however least resistors in signal path. Each step contains only 2 resistors which present a set impedance. Most consider Ladder the best sonic implementation.

This is where you want to be: diyAudio

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Well, considering I’ve heard Paul explicitly state this:
A potentiometer sounds best when maxed because it’s less a resistive (and by mandatory extension, reactive) component in the signal chain.
What’s the consensus? I know, the pot can be of sufficient quality for the detriment to be inaudible, sure, but technically is there any reason not to max the pot while keeping input voltage suitably low?