SACD multi-channel and NAIM

Posted by: Hans 67 on 19 October 2003

Hello all,

first of all I want to say that I prefer mono. But most stereo recordings are not mono compatible thus I use a stereo setup with a Nait5.

Nowadays SACD is becomming more and more important (still not important). And SACD has besides stereo also an multi-channel part. Now I am afraid that the future will be multi-channel.

SACD has no digital-out, thus there are 5 analog channels comming out of the player. I think that the Naim AV2 can not handle 5 analog channels (if I am wrong then explain me why and how I must connect them). Thus then I need an analog 5-channel preamp. And I can not connect a Naim power amplifier directly to the ... preamp. Thus needing preamplifiers from Naim to connect between??? This will get really expensive!

It is just a thought. I hope that I never need a surround system.

But, if I upgrade my stereo setup now with Naim then I am not flexible for the future.
Question is, shall I upgrade my system with Naim or am I leaving Naim for more flexibility?

I also want to know what kind of products Naim is planning regarding multi-channel.
And how about earthing with an AV2?

Greetings, Hans
Posted on: 19 October 2003 by Geoff P
Hans

The AV2 CAN handle 5 analog channels in. through the two so called "versatile" Din sockets Vl1 & Vl2 which can be "ganged" together. It requires a pair of special Din to RCA leads but can take up to 7 channels in.

These inputs take line level inputs direct from the output RCA's on the back of SACD & DVD-A players so no pre-amp is needed, that happens inside the AV2. Of course you can then connect naim amplification to the AV2 selecting the amps of your choice from the NAIM range.

You can also use the AV2 as a stereo pre-amp for a naim stereo system with no unwanted circuits involved inside the AV2. It is rated somewhere between a Nait5 and a 112 intermas of quality as a pre-amp.

As far as earthing is concerned I am not sure what you mean. The mains power lead coming out of the AV2 has the only earth you need in it.

Are you are talking about the euro situation of 2 pin mains sockets with no earth?
I have that situation
(WARNING THE FOLLOWING IS NOT IN ANYWAY GARUANTEED ELECTRICALLY SAFE BY ME)
I have all my HiFi kit plugged into two pin sockets and have no problems with "hum" due to lack of hard wired mains earth.

regards GEOFFP
Posted on: 19 October 2003 by Hans 67
Hello,

Geoff, thanks. I did not know this. Now I have understood the manual.

With earthing I mean the star-earth that Naim is known for. With the 2 DIN cables this is not perfect (like 2 RCA's). I must think a while about this.

Greetings, Hans
Posted on: 19 October 2003 by Geoff P
Hans

Do you know you can download an AV2 manual in several different languages from here:

http://216.149.62.210/products/intro_manuals.html

Also in the AV2 manaul the pin conncetions for the Din sockets are shown. Both of the Din plugs used for SACD in have an earth pin. presumably when the din to RCA cable is made up they connect the sheilds from the RCA "ënds" to this pin. I assume that like other pre-amps the AV2 has a "star earth" on the PWB where the din earths all meet up.

regards
GEOFFP
Posted on: 20 October 2003 by Hans 67
Hello,

I do not understand something. See quotes from the manual of the AV2.

"More! Using inputs One and Two in combined mode enables the connection of source components that may already offer multi-channel outputs - DVD Audio and Super Audio CD for example. When operating in combined mode the input channels available on the two DIN sockets are routed, via the av2 output volume control, direct to the output connectors bypassing any internal signal decoding processing."

"More! The "direct" option available to analog inputs routes the signal directly to the output volume control, switching off and bypassing any signal decoding. This is distinct from the "stereo" decode option which digitises the incoming signal and uses internal processing to control speaker channel routing."

Combine these 2 quotes with the table on page 18 of the manual ("direct" means only left and right) and then I am lost.

Does this mean that you can only use multi-channel SACD through the internal ADC and DAC?

If yes, then I do not want a AV2. I want a analog multi-channel preamp.

Greetings, Hans
Posted on: 20 October 2003 by Geoff P
quote:
"More! Using inputs One and Two in combined mode enables the connection of source components that may already offer multi-channel outputs - DVD Audio and Super Audio CD for example. When operating in combined mode the input channels available on the two DIN sockets are routed, via the av2 output volume control, direct to the output connectors bypassing any internal signal decoding processing."


I understand this to mean the signal is not processed and arrives at the AV2 pre-out's as it was output by the SACD or DVD-A source, which is exactly what you want.

quote:
More! The "direct" option available to analog inputs routes the signal directly to the output volume control, switching off and bypassing any signal decoding. This is distinct from the "stereo" decode option which digitises the incoming signal and uses internal processing to control speaker channel routing."


I believe this means if you put a stereo signal from say a CDP into the AV2 and switch on "direct" mode you get that signal delivered to your power amp untouched which again is what you want for pure stereo.
If on the other hand you are playing a 5.1 channel source the DSP in the AV2 can "downmix" that to stereo if you do not have a surrond system or you have another reason for wanting to "downmix" a 5.1 DIGITAL signal (coax or optical in).

quote:
Does this mean that you can only use multi-channel SACD through the internal ADC and DAC?


I think the opposite is true. You cannot apply ADC DAC to the analog inputs from SACD or DVD-A, which again is what you want since signal seperation has already been done at source.

The only small drawback is that BASS management can only be done at source, but this not special to the AV2 it is a fact of life in the way "copy protection" is used for these formats

Hope this helps, Hans. For what it's worth IMHO the AV2 is one of the best soluitons around for the money.

regards

GEOFFP
Posted on: 21 October 2003 by Martin Payne
quote:
Originally posted by Hans 67:
I also want to know what kind of products Naim is planning regarding multi-channel.
And how about earthing with an AV2?



Hans,

you may like to note this paragraph in the specs for the 552.


quote:
A 552 product plan to enable future requirements for multi-channel use has also been incorporated within this project.



It doesn't seem to mention anything similar re the 252, though, and I haven't checked any of the other preamps.

cheers, Martin

E-mail:- MartinPayne at Dial.Pipex.com