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Intractable Problem

I am having a problem and hoping that I might get some useful advice here. Thank you in advance to anyone that might offer helpful suggestions.
My two channel system is not playing equally out of both channels. Specifically, one channel plays probably at 5% the volume of the other.
My preamp is an Ayre K-5xe. My power amp is Parasound 2250. Speakers are
B&W 803-D. Interconnects are Nordost Blue Heaven. There are two digital sources--Oppo 105 and a Denon "Anniversary Edition" SACD/CD Player. TT is Clearaudio Concept from a Music First Phone Preamp.
The problem occurs with all of the sources. I took both the Ayre and the Parasound to their respective dealers and they checked out fine. Changing the interconnects doesn't help.
I put in an old Pioneer Elite receiver and left the speaker wire arrangement (it was tacked into walls by an installer and has worked fine for a year) unchanged. The receiver plays equally out of both channels and all the sources work well with it. This would seem to eliminate the speaker wire/connections as being at fault.
The Parasound dealer loaned me another amp. It immediately blew two fuses when I put it in the system with the Ayre. I think this may be due to the fact that I was using bare wire at the amp connection, and with all the switching in an out of different pieces of gear, I had let some loose ends of wire be exposed. After this happened I bought some Tributary plugs and have carefully trimmed the wire down. When the Parasound was returned it didn't short, at least, but I'm still only getting 1 channel out of the system.
I am pretty frustrated--it's been 3 straight weekends of messing with this, trips to different dealers, etc....and I'm starting to see the wisdom of Integrated Amps or receivers vs. separates. I'm thinking of trading in the pre and power amps and using the $ for an Integrated and be done with it.
Any suggestions appreciated.
richardfinegold
rodman99999
6,158 posts
 
You said that the bad channel is playing at 5% the volume of
the other. If you worded that correctly; there's a 95%
reduction in volume, which could indicate a blown rail fuse,
in the power amp(one of numerous possibilies, but- the
easiest
to correct). BTW: Is your bridging switch fully in the,
"STEREO" position?
almarg's avatar
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almarg
9,670 posts
 
Lots of good thoughts by the others above. Like several of them, I too am not clear on a number of things, especially whether you have performed the usual troubleshooting procedure for problems that affect a single channel. Namely interchanging connections between the two channels at various points in the signal path (with power off while the connections are being changed, of course), to isolate where in the signal path the problem is arising. Also, as Newbee asked, when you said:
When the Parasound was returned it didn't short, at least, but I'm still only getting 1 channel out of the system.
Which amp were you referring to, the loaner or your own?

Another question: When the dealer checked out the Ayre preamp, do you have confidence that they checked the RCA outputs (which I presume you are using), or might they have just tested the XLR outputs?

Also, if by any chance, and for whatever reason, you are using the Ayre's XLR outputs in conjunction with XLR-to-RCA adapters let us know, as the output stage of the preamp might be unhappy with the fact that most adapters short the inverted signal on pin 3 to ground (pin 1). If you are using such an adapter it would quite possibly explain why the preamp works for the dealer but not for you.

Another thought to keep in mind, in addition to those that have been suggested: Perhaps one channel of the Ayre is not functioning at all, due to a failure at some point in its internal signal path, and the 5% signal you are hearing in that channel is crosstalk (leakage) into that channel from the other channel, occurring either in the power amp or at some point in the Ayre's internal signal path that is downstream of the problem location.

Regards,
-- Al
richardfinegold OP
196 posts
 
Up date

1) First of all, when I switched interconnects between the pre and the pro, it didn't change anything. Nor did switching the ic from left to right channels change anything. Reversing the speaker wires from 1 channel to anothe didn't help either.
A friend loaned me a Cary Pre amp to try. It also could only make the Parasound play out of 1 channel (for the first few minutes I thought it was both channels, but then 1 channel stopped playing). The Parasound played perfectly at the dealership-- I heard them play it without difficulty from both channels.
The receiver continues to play music equally from both channels.
The problem must be in the power amp, but why did it play perfectly at the dealership? I didn't get the loaner power amp back after I had blown the two fuses in it. I tried making the receiver do a pre amp out into the power amp but I can't figure out how to do it on the remote.
zd542
5,339 posts
 
"I tried making the receiver do a pre amp out into the power amp but I can't figure out how to do it on the remote."

To check the amp by itself, turn the gain controls on the back of your amp all the way off and then plug a CD player directly into the amp. Then just use the gain controls for volume. (I'm assuming that you tried what I recommended in my first post and it didn't help. If not, do that first.)

To check the preamp by itself, plug it into a headphone amp if you have one. If not, plug it into one of the inputs on your receiver. If the receiver has a pure direct mode, use it. If it doesn't, just make sure that everything is set flat. Be sure to start off with both volume controls turned all the way down and bring them up slowly
truemaineiac's avatar
truemaineiac
249 posts
 
This is just a wild hunch but I would try another set of speaker cables with your amp to those speakers. It seems like it is something with the speaker wire if you switched speaker wire between channels and nothing changed (same speaker playing at 5%?).
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