Salas DCG3 preamp (line & headphone)

This is probably bit off topic, but do you have any suggestions for reasonably priced audio grade rotary input selector switch and stepped attenuator for volume control? Input RCA terminals will be at the back, but the input selector and volume control at the front. Planning to use extension shaft.
I am trying to make things as simple as possible for now, so no additional boards with relays etc.
 
Just what I needed. Thank you Salas!

So this is probably an obvious thing to most here :) I'll need to match DN2540 mosfet, what is the procedure/schematics to measure Vgs? Ordering from mouser, how many do you think I'll need to get matched pair? According to Hikari in post 839 it came very well matched, so planning to get only 5.
 
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Heat sink came today so hopefully will be able to solder the Mosfets on and test.

Spent a while tonight cranking the fets so they will align flush with the heatsink

Mosfets not soldered here so they aren't straight yet....then I have to drill and tap the thing nicely!
 

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I state that I have not read all the 350 pages, but only the first 50 pages.
from the diagram on the first page I see that we have used a chip for the servo circuit for the DC.
To control DC is not able to do otherwise?
always avoiding the use of capacitors in output, okay !
the question because I have always noticed that the presence of a servo circuit affects much on the low range, even if placed in parallel the signal

the absolute selection of the input j fet couple and place them in close contact with each other to even out the temperature variationdoes own allow to control the offset too?
and not even placing a multiturn trimmer between the emitters of the 2 j fets in input?
I ask
 
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