foreplay III input crosstalk

[khingila]

i've been happily using an extended foreplay III for the last year or so, and just today have gotten around to changing the padding resistors on one input to balance the output levels between my njoe tjoeb cd player and the other stuff i have plugged into it. while checking to see how it turned out, i realised i am getting significant crosstalk between input 1 and input 2, when there is no connection made to input 2, and as well when there is, whether or not it is playing. i'm also getting less obvious but still audible bleed-through to input 3. i don't know if this was the case before, because i'm not in the habit of playing more than one source at a time. i did nothing but replace 2 resistors, and my resistance readings all check. is this to be expected?   

[Paul Joppa]

Raising the resistance makes capacitive coupling stronger between nearby wires. With shunt-mode controls like these, there is also some increase when the signal is disconnected from the level control.

Connect the loudest source at the opposite end from the quietest one. You can try to keep the input wires spaced from each other, as much as practical. You could insulate each series resistor with heatshrink, then use shield weave around them. Ground the shields - a bit of a challenge since so many things are grounded at terminal 28 already! In extreme cases, a different switching arrangement can be used, with grounded (dead) positions between each signal.

But it's a lot easier to just silence the source you're not listening to.  :^)

[khingila]

easy enough! thanks very much; just wanted to be sure i hadn't screwed up something.