I had just 1 channel (for example, the left channel) from my preamp running in to my amp and I could hear the signal coming out of the left channel!!! While this amp works very well normally, I cannot help but think this is a major flaw, especially since this is supposed to be a dual mono design.

Is there any other explanation for what's happening? I would very much appreciate it if other A3Cr amp owners would try running only 1 channel in to their amps and see if they can hear both channels.

 Re: Help! Musical Fidelity A3Cr amp owners! - DKC 04:44:11 09/06/02 (0)
 I know the answer. - Wordsmith 22:37:47 08/31/02 (8)
 Re: I know the answer. - Greg Cz 19:20:24 09/02/02 (0)

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 Re: Help! Musical Fidelity A3Cr amp owners! - DKC 04:44:11 09/06/02 (0)
 I know the answer. - Wordsmith 22:37:47 08/31/02 (8)
 Re: I know the answer. - Greg Cz 19:20:24 09/02/02 (0)
 Re: I know the answer. - nousaeous 12:08:12 09/01/02 (4)
 Are you testing fro crosstalk properly ? - john dem 13:25:22 09/01/02 (3)
 Re: Are you testing fro crosstalk properly ? - nousaeous 14:44:15 09/01/02 (2)
 Well, dual mono usually means - john dem 15:44:32 09/01/02 (1)
 Any well designed amp should be dead quiet... - Gepetto 19:09:09 09/01/02 (0)
 I guess it really is a DUAL MONO amplifier then... - Gepetto 09:17:25 09/01/02 (0)
 Re: I know the answer. - Porkless 03:57:31 09/01/02 (0)
 correction: Re: Help! Musical Fidelity A3Cr amp owners! - nousaeous 19:08:11 08/31/02 (0)

"I had just 1 channel (for example, the left channel) from my preamp running in to my amp and I could hear the signal coming out of the left channel!!!"

should be

"I had just 1 channel (for example, the left channel) from my preamp running in to my amp and I could hear the signal coming out of the other channel!!!"

Reposted corrected version below:

While rejiggering my system, I noticed some pretty obvious channel crosstalk.

I had just 1 channel (for example, the left channel) from my preamp running in to my amp and I could hear the signal coming out of the other channel!!! While this amp works very well normally, I cannot help but think this is a major flaw, especially since this is supposed to be a dual mono design.

Is there any other explanation for what's happening? I would very much appreciate it if other A3Cr amp owners would try running only 1 channel in to their amps and see if they can hear both channels.

Other Asylees have mentioned the same problem, and this was one of the main reasons I did not buy the A300 a couple of years ago. I just could not adjust to the idea that I was not going to hear each channel where it should be and nowhere else.

Also, if you have two sources attached and turned on but only one playing, you may be able to hear it when selecting another source - another case of breakthrough.

You are right about it being a major flaw. This is simply a case of poor design - particluarly when they make a lot about their stuff being dual-mono amp's.

Best regards,
Wordsmith

What's surprising is that this amp got great press. Why is it that a supposed major design flaw has not been exposed or even much discussed?

Is there something I'm not getting?

Shouldn't you check for crosstalk with the unused input shorted ?

Maybe one of the helpful engineers here can assist with a simple test for crosstalk which will reassure you that your amp is within its spec.

Shorting plugs on unused inputs is a good idea anyway- check the Tweakers Asylum archives for more info.

good luck

john dem, fresh from some very cross talk at the Vinyl Asylum

The proximity of the leads/tracks from L and R however can be very tight on a particular input, or throughout an amp- I'm sure one of the designers here could give some more detail on how proper design and layout can minimize problems, but with one unconnected input on your power amp picking up and amplifying signals from the nearby active channel(s)- you may expect some crosstalk to be audible.

I have a test cd somewhere from Denon with test tones on each channel for crosstalk measurements- maybe you can hunt up a similar CD and check the crosstalk with some degree of certainty.