Balance Control Operation?

[eickmewg]

So, how does a typical balance control work? Does it have something like two wipers that are used simply to attenuate the right of left channel signal voltage by shunting some voltage to ground depending upon knob position? I.e., when turned to the right, attenuating the left channel signal leaving the right channel signal unaffected and vice versa? Or does it simultaneously amplify the right channel signal while attenuating the left channel signal? Seems like the first scenario is the simpler of the two.
The reason I ask is that my current preamp has no balance control but my room configuration favors the left channel in addition to some hearing loss in my right ear. I want to use a simple add-on line-level volume control but only insert it to the left channel to attenuate the left channel signal leaving the right channel signal unaffected. Will this mimic how a regular balance control would work but be limited to the single left channel?

 

[lini]

Implementations vary, but the two usual ones are either a mono pot with the two ends between the two channels, wiper contact to ground, or a stereo pot basically wired just like a volume control, but with one channel wired in reverse, either using a regular stereo pot or a special pot with half of the taper of each channel being a solid metal contact with nearly constant near zero resistance. So with such a stereo pot variant only one channel would be reduced in level, whereas with a regular stereo pot one would be reduced and the other increased, at least relatively (absolutely one would be more and the other less reduced).

Your variant intended variant would be similar to the second variant, using the special pot, but only one of its channels. However, that wouldn't seem an all too great idea to me, 'cause, as seen by the output, the load in the channel with the extra pot would, pot turned up to the maximum, be the pot resistance in parallel to the input impedance of the next stage compared to just the input impedance of the next stage for the other channel.

Greetings from Munich!

Manfred / lini

 

[rlisin]

It usually only attenuates one channel and leaves the other unaffected. I only remember one or two amps in which balance control attenuated one channel while increasing volume level in the other. So your solution is consistent with how balance pot normally works.

But: then you will have an additional device (line level volume control) in one channel but not in the other. I would add identical controls in both channels, but only adjust the left channel.

 

[the skipper]

Your solution should work although it's cumbersome and shouldn't be necessary.

Now, the "audiophiles " here will want to crucify me, but here goes.

Why they ever decided to do away with balance controls is beyond me. Not many people can place their speakers and listening position perfectly. A balance control comes in mighty handy to compensate for those situations, which affect most people. I'm sure he mastering engineers know where we're sitting in relation to the speakers and room acoustics, don't they?

Heck, why not do away with volume controls, too. They must know how loud we should listen to it too, right?

FWIW, I feel the same way about ton controls. I rarely use them but on rare occasions, a poor recording can benefit from a tweak at the extremes.