Building a symmetrical PSU B1 buffer

Check out this page for some direction on mains wiring. You certainly need to understand exactly what you are doing with this part of diy. The fun can come to a screeching halt real quick if you don't. And please be sure to use heatshrink tubing on all of the exposed terminals and connections.

Power Supply Wiring Guidelines

These are good assuming you can reach round the back of your DCB1 to turn on and off.

MULTICOMP|JR-101-1-FRSG-02|INLET, IEC, DPST, WITH FUSE HOLDER | Farnell United Kingdom

Thanks! I have a good direction now.
 
I....guess....this could even be considered an alternative for your power switch.

(Be careful. Wiring "mains" circuits can be deadly. Have an experieced friend assist you--and have them double-check your work)
 

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Salas,

If I want to hod rod the DCB1, would the heat sink on the BOM sufficient?

Would the measurement any different between standard and hot-rod ones (like DC offset)?

Thanks!


No its not sufficient. Get 1C/W common sink per rail Mosfets or use a sturdy metal plate enclosure floor and mount Mosfets like in some power amps under PCB (like they do sit ups). Isolation pads are necessary when the Mosfets backs are on common metal resting place, else...smoke. Yes, they will measure a little different for current setting some times because Vgs of Mosfets changes with current and temperature. Also the audio Jfets can change offset a bit in a hotter environment. Anything under 5mV is not alarming.
 
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Thanks Salas,

Hope so, I want to combine it with the F5 (also in progress). LS are Dynaudio S25. I know they are supposed to be thirsty but at the moment I am using them with a 14 yr old class A amp, 2 x 18 watt, loud enough.

The problem is mainly voltage gain. The F5 will need 2.5VRMS to give its rated power. With a buffer all this must be available from your source. Your other amp may well be more input sensitive although 7W weaker on 8R load. Do you know your source's voltage output?
 
@Salas,

I am using a previous version of the Linn Akurate DS. Here some specs from their website, since I don't know how to measure this:

Output voltage 2 V R R MS (0 dBFS , vol. 80)

The present amp is A-18, Hawk, designed by John van der Sluis, Netherlands, see scheme. No pre-amp just a 100k log pot.
 

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If the amp schema had values we could figure out the gain, has enough open loop gain to allow set it conventionally as far as the topology hints. To check any CDP's RMS output, a 0dB sine wave from a test CD (preferably below 1kHz) and a DMM set at VAC would show.