Prefix into NAC 'phono' input - what goes ?

Posted by: DIL on 02 July 2002

Hi,

I'll start with a quick question for anyone with a Prefix. ( I am about to aquire a s'cap for my 82 big grin , leaving my hi-cap looking for work confused . )

Do I assume correctly that my present phono cards sit behind Input 1 and that these get replaced with 'straight through' cards if a Prefix is used ? If so, does anyone remember if these are included in the cost of a Prefix ?

And for the rest of you, and not for the first time on this forum, any other suggestions given that I have a bare Cirkused LP12 (i.e. No 'Geddon/Lingo.) running an Ittok LVII / Klyde. To make matters interesting, my local Linn dealer has an Ekos - don't know if it is an early or late one - for ca. £650.

/david
Posted on: 02 July 2002 by DIL
I guessed that the line level output from a prefix could be fed into any of inputs 2 thru 6.

However, not being able to select my TT by pushing the button marked 'phono' (as opposed to VCR, Tape or whatever), rather offends my sense of design aesthetics. Same as having to adjust volume when switching between TT and CD player. Surely on a pre costing ca 5k (with s-cap) .....

Maybe I need the programable inputs of the 552 ? (If I understand things correctly).

/david
Posted on: 02 July 2002 by Martin Payne
David,

BNCs are the socket of choice for connections from the cartridge to the preamp.

The Prefix removes the need for this connection completely. It is either part of the preamp or a source component, depending how you look at it.

Either way, it's DIN sockets all the way from there to your 250. It will connect into any one of sockets 2-6.

Please note that sockets 2 & 3 sound much better than the others. Make sure the CD goes into one of these.

You may also like to try your Linn CD into the BNCs, although you will require straight-through boards (£20-ish) and a phono-to-BNC cable.

Please note, your LP12 is currently providing an earth for the system. With the prefix, it might not.

Your CD is probably not giving an earth, so this might be a major degradation for your whole system. If your CD quality degrades, you will need to provide an earth direct to the binding post on the back of the 82.

Regarding your LP12, I would suggest either an Aro or a power supply. If you go for a Lingo, ensure you do the Weekes mod. JV always recommended the Aro first, then the PS.

cheers, Martin
Posted on: 02 July 2002 by Martin Payne
quote:
Originally posted by Sue Needham:
You can prise off the labels (carefully!) with a Stanley knife and reposition them as you wish. Just push the blade under the bottom edge and flick it out. The labels are self adhesive.




"Sue" is quite right.

I have swapped the CD & tuner labels on my pre:-



Now I just need to swap the "phono" & "tuner" labels since getting my Stageline.

cheers, Martin
Posted on: 02 July 2002 by Jens
Hi Martin/Sue,

How risky is this procedure? Is it easy to stuff up? Since getting my Prefix the only source that is correctly labelled on my 82 is the CD player. As David says it would be nice to change the labels over. Have you got any tips for us to follow/avoid?

Cheers, Jens
Posted on: 03 July 2002 by Andrew L. Weekes
quote:
Please note that sockets 2 & 3 sound much better than the others. Make sure the CD goes into one of these.


I find it difficult to believe that what was, until recently, Naim's second-from-top of the range preamp, and a not exactly inexpensive piece of kit, is so badly designed that there are significant differences in quality between the inputs.

Oh, I know, it's actually so good that the differences can be heard wink

Tell me this is just some Naim user hyperbole, please!

A.

[This message was edited by Andrew L. Weekes on WEDNESDAY 03 July 2002 at 09:21.]
Posted on: 03 July 2002 by Andrew L. Weekes
quote:
The prefix has an earthing cable (two actually) that is connected in the usual manner to the NAC to provide system 0V.


Mine only had one!

The Prefix earth normally only earths the Prefix enclosure, and does not connect to the TT chassis.

I've just asked my dealer to make this connection for me, whilst my TT is in for a service, it's not a safety issue, just it provides a drain static buildup from the deck.

A.
Posted on: 03 July 2002 by P
If you speak to your dealer you might be able to get hold of a new set of sticky lables like this one.



I've had these for a while now so I'm not sure if the Part Number(as per the JPEG) is the same

HTH

P
Posted on: 03 July 2002 by Martin Payne
quote:
Please note that sockets 2 & 3 sound _much_ better than the others.


quote:
Tell me this is just some Naim user hyperbole, please!



Andrew,

hmm, yes, think the wine was talking a bit yesterday.

But they do sound somewhat better - apparently an unavoidable result of the extra record-out pins in the sockets themselves. (Someone from NANA posted to this effect within the last couple of months. I rememver Dev contributing to the thread, too).

Note that on my (v. early) 52 sockets 5 & 6 also pass through plug-in boards. Later revisions dropped this facility. Actually, I can't really see why anyone would need it.

cheers, Martin
Posted on: 04 July 2002 by Martin Payne
quote:
Originally posted by James:
Not quite, the 250 input socket is a 3-pin XLR.



James,

See, I have twelve of them...



cheers, Martin