Seperates do make a difference...NAD integrated made me frown. (1 Viewer)

[Aaron Howell]

Well I bought my NAD integrated this past winter. FWIW, I have loved every minute with this unit until this event occured.

This past weekend I moved my NAD C370 integrated. For S&G's I decided to play with different cables and see if I could hear any differences.I had tried different things and came to the conclusion that as long as they had good sheilding, I couldn't really tell a difference.

Then I came to the rca "clips" that connect the Preamp to the Amp. These are basically "U" clips since the rca's for the preamp out and amp in are right next to each other. I looked at them and thought, "Wow, no sheilding at all...this should make huge a difference." Well, when I took them out something strange happened.

I STILL HEARD MUSIC!!!!

It wasn't loud, but with the volume at 3/4 it was audible. My Ratshack spl meter could not detect it, but I could hear it....even though the preamp and amp where physically disconnected from each other.

It also didn't make a difference if I used sheilded cables going into the preamp or not. That tells me the internals are not sheilded enough from each other. I was starting to think about sheilding the internals better, but came to the conclusion that it's not really worth it. I was just sad cuz this was the first flaw I found with the unit. :frowning:

Has anyone else had this happen with their integrated amps?

 

[John Garcia]

I noticed the same thing on my friend's Marantz 9200 when installing it. I had removed all the jumpers during moving and forgot to install two to test it out, but there was still a little signal getting through. It was faint, and I had to crank the receiver nearly to max to hear it, but it was there. To be honest, I don't think this is really a problem, it's more or less normal. If you could disconnect the pre and amp section in most receivers, I bet you'd be even more disappointed. The thing is, when you disconnect the jumpers, that signal has nowhere to go, and the output stage will pick it up, but if it IS connected, I don't think it's an issue.

What cables did you try, and what methods, just out of curiousity?

 

[Jack Gilvey]

Why exactly has your apparent discovery of a little internal crosstalk ruined your enjoyment of your amp?

 

[Adil M]

Probably b/c he is imagining a compromised noise floor and dynamics. He has probably always been curious at the advantages of "separates."

 

[Lee Distad]

I'm intrigued by this. So, out of interest, I went to our CAD$649.99 Yamaha AX596 2-channel integrated, and unplugged it's EQ-loop jumpers. Only with the volume dial absolutes pinned was there even the faintest volume coming via cross-talk.

I got no real point here, I just decided to monkey around on a slow day.

p.s. a better title for this thread would be "NAD makes me sad!!! :frowning: "

...nothing against NAD, I just like the rhyme.

 

[Aaron Howell]

It hasn't ruined my enjoyment of the amp at all. It was just the first time it wasn't perfect. But I know it is a minor issue, and I don't really care...but it did give me a small frown at the time. If it really bothered me I would be doing something about it.

For the record, I have loved every minute with it since to.

 

[Chu Gai]

If you've got a couple of spare, junk, RCAs, short them and place them on the pre-outs with those little jumpers disconnected. If you don't have those, get some aluminum foil and tightly wrap the pre-outs. Still hear anything?

 

[Aaron Howell]

You mean just cut the ends off some cheap rca's and put them on the rca connectors to see if that sheilds them any better?

Edit:
Now that I think of it, I will hook up two sets of some mediocre(the best I have, tributante or something like that) rcas to the preouts. One set to each pair, but not connected. That will truly determine if the crosstalk is occuring from inside or outside of the unit.

 

[Jack Gilvey]

Ahh, ok, good. I took the "until" from your first post to mean..."until".

 

[Chris PC]

As was mentioned, when the regular signal is reaching its destination through the proper connection, whatever tiny bit of residual signal probably won't affect the sound output quality. Even if there were conflicts, in that the tiny signal made its way to the ampilifer section along with the normal signal, wouldn't it not only be dwarfed by the main signal, but possibly even diminished further through feedback noise cancelation.

 

[Chu Gai]

The question is if the reason for this signal is due to internal leakage or is it because of the proximity of the pre-outs to the amp-in in which case we could hypothesize something entirely different. Apart from blocking, I'd imagine that you could just attach a pair of analog or video interconnects and keep the other end far away. Something I'll try later this evening.