The Singing Bush

Just Now! both PSU units are tested and ready to go! CLC filtering om both positive and negative, and classic CL60 inrush limiters.

The rest of the PSU-capacitors will be divided in each of the power amplifiers. 🙂

The Form factor of the PSUs chosen for this build are exactly a vinyl record box set, with rubber feets. 🎺🙂🎸

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I was looking for the rectifiers and think I found them (if not you would probably have experienced a loud "bang").
It is a single supply with a DC filter choke in what normally could be Gnd?
Ok.....audio ground will be in the amp chassis at bank of capacitors (at the + as it is a negative supply voltage?).
I was wondering a bit about the safety ground if you transfer this to the amp chassis and also if you have a reference from audio ground to chassis?
My concern was to avoid ground loops........caused by the yellow/green wire to both chassis........with the special DC filter choke arrangement. But I should probably not be concerned 🙂 .......it looks very good! ......and the small toroid is maybe for the "future"......to drive some relays.....as discussed.
 
I made a quick hand drawing of what I think the concept is. It is late night so I could have made big mistakes.......but if the concept is like the hand drawing with only one reference from audio gnd to chassis and audio gnd is defined in amp chassis only I am not concerned.
The reference from audio gnd to chassis could be resistor, CL60, galvanic, bridge etc......the resistor symbol is just made to indicate the reference.
 

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yeah

in short:

PSU case must be connected to safety GND

Amp case must be connected to safety GND

PSU is floating (totally) in PSU case

in amp case, connect (finally) established GND to case through whatever - NTC or NTC//Bridge or NTC//Bridge//cap

there are few other ways to it, while still totally safe, but only this way there are no surprises if by chance PSU case touches AMP case
 
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Yes like you both are explaining it, is how it is being and, and is planned to be built. This would be equal to the configuration in my current Aleph Js, with the amplifiers audio ground point lifted with the NTCs, from the case safety ground. 🙂👍
 
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One thing I maybe would be a bit concerned about is the filter caps placement directly on chassis. Usually the aluminium can itself is "minus" (you can measure)?
The can has plastic insulation but the bottom is not fully insolated. The chassis has "plus" reference so if a can is bugling a bit out "something" could happen. Now aluminium has natural oxidation which will help the electrical insulation but I just wanted to mention it 🙂
Also the amp chassis gets quite hot which could soften the insulation a bit.
 
Yea, thats true. And I will surely learn/try PCB creation and design some day, in some future build.

But i really like the solid look and feel of the really old school point to point wireing.

Its just a personal nerdy thing. 🙂🙂🙂
 
Power supply done mounted in the chassis, both channels done. I just need to finish mounting one channel to its heatsink then it's time to wire up each channel and bias. I'm not quite sure what I was thinking about when I put this massive amplifier and supply in a single 5U chassis.......this thing is heavy and I put the chokes in the back to help the C.G. (center of gravity) 🙄 I ordered some massive rubber pucks to replace the Modushop feet as I think this amp would have shattered them.....

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