Salas DCG3 preamp (line & headphone)

Actually will take me a day or two longer as I need to get some de-solder braid because I don't want to damage the PCB and want the MOSFETs for testing.

Anyway many thanks for your fast and really helpful support so far. I will report back.

Cheers
 
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.
 
Hi Salas

I am really pleased with my DCG3 and recently added an arduino rig to control the relays and the volume pots..... but I would like to even get better bass..... Would a change to BC327 help in this region ?

What are the real benefits of this mod ?
 
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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