I have just acquired a s/hand NAC 72 for use at work which is marked on the rear/box as a 72N(it had MM originally). It has 323/5 phono boards which I know are moving coil boards but I don't know if they are S or K type.

Can anyone tell me how to spot the difference by looking at the boards themselves?

K boards have a little gold circular sticker on the board itself with a black 'K' on it.

From Frequently Asked Questions:
http://forums.naim-audio.com/eve/forums/a/tpc/f/3452929996/m/9242922307

If you look at the above linked pictures, the differences are in the input capacitor: on the bottom left corner:
IIRC: K boards 2N2, S board 6N8. if you want an affirmative answer, you'll have to wait untill Monday, i'll look at the schematics.

quote:

Originally posted by Dave996:
K boards have a little gold circular sticker on the board itself with a black 'K' on it.

Dave,

but the stickers do fall off sometimes.

cheers, Martin

Later 72 "K" boards have the round K sticker on the end of the capacitor.

Keith