seperate power supply

[Chrisr3521]

having wanted to give my old nakamichi amp 1 a little boost i was looking to put seperate power supplys for all the various bits (power, pre amp, eq boards etc) but not wanting to skimp i'm looking at 600va torrids which will not fit in my chassis, hence why im asking you guys about a completly seperate power supply for the amp.

And was also wondering on the best way to implement this as regards to the way of getting the volts between the boxes, would it be better to house just the torrids in a seperate chassis and have the rectifer, caps etc in the original amp chassis so to leave the dc lines as short as possibe?

i' ve hope i made sence

thanks

chris

 

[gmphadte]

It would be better to replace the rectifiers with higher current rated devices. The toroid and the diodes better be away from the amp. I would also suggest to wire some filtering caps in that box. but not the existing ones. Let them be where they are.
The opposite polarity wires should be twisted.

Gajanan Phadte

 

[AndrewT]

Hi,
keep the transformer and rectifier and first stage smoothing capacitors in a compact tight loop. This demands that they MUST be kept together.

Retain the decoupling caps inside the power amp. Even replace them with higher quality and possibly higher value if they were compromised in the original. The sound quality is more influenced by the second stage smoothing/decoupling than the remote caps.

Run separate DC at a higher voltage for the other PCBs. Use local regulation for each low current supply.

Consider mains voltage safety and how you apply a Safety Earth to each of your separated enclosures.
The exposed conductive parts MUST be connected to Safety Earth. That includes RCA input sockets and speaker terminals if anyone can touch the metal parts. That's why Cyrus and others adopted enclosed/shrouded speaker terminals on their double insulated enclosures. I don't know how their RCAs comply!!