MPP

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Joined 2006
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I am using the 6800pF caps and 130k for starters.

As for the 15k I will use 15k // 16k2 and trim the 40.8 cap accordingly.

If it has too much treble (subjectively) I will add some picos to the 13.6nF cap also.

If I feel that the sound is too bass heavy and lacks bite, I will parallel something to the 65kr ... I will let you know.
 
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Joined 2006
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I have now stuffed the SMDs to Michaels board. The values i got are :
Channel 1 : 13,97nF , 41,6nF
Channel 2 : 14,01nF , 41,5nF
The caps all measured slightly high so i assume that my cheep LCR meter errs in the positive direction too, so the values will be somewhat lower in praxis.

IMO, the trebble caps are very good.

In your case I would try to use 7650r in series with the 41.5 caps

That can be done by using 15k // 15k6... that way you have Time C = 318.2 (Freq 500.1), very near the ideal 318 (500.5Hz)
 
The caps solder easy. I put a small "point" of solder on one pad, then i place the SMD cap and push it down where it should be. Then i heat the "point" or call it "spot". The cap is notw fixed to one side, although only in a little space. Then i solder the other side and then i finish the side where the "spot" fixing is. I make sure that the solder joints look shiny and give a "minimal" surface that looks like the roof of the Olympia stadium in Munich.
 
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Joined 2006
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Just completed all connections and fired the rig.

Right Channel:

Shunt outputs are
+24V (I can adjust it with the trimmer)
-35.7V (I can NOT adjust it)

Input offset -2.5mV to -1.9mV oscilating (When I switch off, this offset starts rising until it reaches 30mV and than goes down)

Output offset Wild oscilation between +12 and -10V

On switch on, opamp leds light imediately... after a while the negative shunt leds light up and 5 seconds latter finally the positive shunt leds light

Left channel:

Shunt outputs are
+21.4V (I can not adjust it and the leds are very dim)
-24V (I can adjust this value with the trimmer)

Input offset: 9.6V steady
Output offset: 12.75V steady

Leds on the opamp flicker.

This is going to be harder than I was hopin for :(