If the answer is blindingly obvious then forgive me. I've asked the dealer who sold me the kit and he doesn't know either..............
If I add a add a power supply to my 92 preamp, I'm adding a second 24V rail.
Question. Where or what does that second supply power? Does the blanking plug (in the 5 pin socket) play any part in bridging a rail perhaps?
Do the supplies go left and right? Phono and the rest??
And this is the comic spooky bit..... How does it know it has a second supply coming in; and how does it split a rail that was previously powered by just one supply to take advantage of the second supply.
Or is it all a load of b@ll@x and Naim's just taking us all for a ride 
Confused of Hants
Posted on: 18 December 2001 by Mike Hanson
If you are using your power amp (NAP90?) to supply the 92, then the single rail of power is provided via the 4-pin SNAIC. The shorting plug is connected to the 5-pin socket on your 92, and it bridges the two rails there, so that the single rail supply from the 90 is shared by both rails.
When you add an external supply, it uses a 5-pin SNAIC and it plugs into the socket currently occupied by the shorting plug. The 4-pin socket will be vacant. The 4-pin SNAIC from the power-amp plugs into the Hi-Cap or Flat-Cap instead of the 92.
-=> Mike Hanson <=-
Posted on: 18 December 2001 by pm
Thanks Mike,
I half answered my own question after I put a multimeter on the plug and found continuity on the two 24V pins.
However, (without dismantling the pcb to look underneath at the tracks), I can't see what the separate rails power. Any ideas?
Posted on: 18 December 2001 by David Dever
Left (or 4-pin rail): phono boards + input buffer
Right rail: output stage, relays (24V in Series 3 stuff), front panel switching circuits
Dave Dever, NANA
P.S. Note that, in a HICAP, the left voltage rail has fractionally lower noise--good for sensitive circuits as listed above.
