[bg4533]

What is the difference between a source driving a 32ohm (or whatever) pair of headphones and a 50k pot? I mean if the source is strong enough to drive the headphones why must the value of the pot be so high? I am guessing they appear differently to the source, but how so?

Is there a way to determine which value of pot is ideal? It is probably safe to assume that portables would prefer a higher value pot than stand alone sources, but are there any specific methods available to the average DIYer?

I have heard that noise goes up and channel seperation goes down as the pot value goes up. To what extent is this the case? Could a 10k pot actually sound better given a powerful source?

 

[AndrewFischer]

Quote:

Originally Posted by bg4533 What is the difference between a source driving a 32ohm (or whatever) pair of headphones and a 50k pot? I mean if the source is strong enough to drive the headphones why must the value of the pot be so high? I am guessing they appear differently to the source, but how so? Is there a way to determine which value of pot is ideal? It is probably safe to assume that portables would prefer a higher value pot than stand alone sources, but are there any specific methods available to the average DIYer? I have heard that noise goes up and channel seperation goes down as the pot value goes up. To what extent is this the case? Could a 10k pot actually sound better given a powerful source?

50K is compatible with a wide range of sources.

10K should be fine hooked up to the headphone jack of a PCDP. 10K is a bit low for a 12AX7 tube output from a Tube-Dac or an all tube pre amp.

 

[tangent]

Quote:

if the source is strong enough to drive the headphones why must the value of the pot be so high?

First, that's a big "if". You're clearly only considering portables with headphone outputs only.

Second, the higher the input impedance the lower the load on the previous stage, and so the lower the distortion. If we made the input impedance 32 ohms, then you'd have a nearly complete "weakest link" situation: the amp would be loading the source almost exactly like headphones, so it wouldn't be taking the load off it, so it wouldn't be reducing overall distortion. We'd put the input impedance of our amps up in the megohms if we could get away with it.