I have a new stereo system, bought in February (B&W 603 s2, Sony CD player, Cyrus 5 amp, forget what the cables and interconnects are) which has started behaving strangely since it moved house with me. It was absolutely tip-top before we moved, but when I set it up in the new place I noticed something very odd.
When playing certain CDs I notice that one or two tracks in some songs are missing. It might be a lead line (“got myself a good man” by Pucho and the latin Soul Brothers now has no lead trumpet line, “6 Underground” by the Sneaker Pimps now does not have that guy saying “A-one two a-one two” throughout the song, arguably an improvement, but that’s not the point) or it might not, and it is only noticeable on certain tracks. The effect is very strange, it is as if someone at a mixing desk has just cut the track right back, and if you listen very closely, you can hear the line as if it’s being played in an echo chamber 3 miles away. I’m pretty confident its not the speakers – a mate who is an engineer for B&W checked them out. I replicated the effect using a CD discman, same tracks missing from the same songs. Headphones connected to the CD or the amp reveal the missing line in all its glory, but cut out other lines instead – but I think the headphones are dodgy anyway. My suspicion therefore falls to the amp.
My question – has anyone heard of this before? My audiophile friends are scratching their heads and on the basis of a telephone conversation the guy at the shop is mystified too. The gear is warrantied and I will be taking it back to get it fixed, but rather than take back all my kit, can I whittle down the suspects?
Sounds like you’re only hearing one of the stereo channels.
Thanks, mangetout.
I thought of that but can’t square it with the effect. The symptoms sound identical through both speakers and are totally specific to the one track in each song that is affected. Surely if it was the case as you suggest more than one track would be affected, or it would only be noticeable on one speaker?
j.
I’m no expert when it comes to exactly how stereo info is encoded on a CD, so I couldn’t say, but maybe it’s just that the tracks where the effect isn’t noticeable simply don’t have that much difference between the two recorded channels.
Perhaps someone on the board here could suggest a song that has very noticeable stereo effects (like maybe the male and female parts of a duet on separate channels?) that you could use to test it.
I can think of a couple of tracks with extreme stereo separation, i shall try that.
cheers,
J.
That really sounds like an open ground. I came across that quite often when repairing consumer electronics. Now, where could the bad joint be? Most commonly at the speaker terminals or the line input jack. Do you also hear this in the headphones? If so, it’s probably the input jacks. Is it specific to one input? CD only? Then guess which jack it is 
Permenant fix: Open the thing & resolder all ground joints near the input terminals. Cold (broken) solder joints are usually pretty easy to spot.
Jury rig: Use an aligator clip to make a redundant ground between the RCA cable shield & the chassis.
Don’t do the jury rig at the speaker terminals, unless you are absolutely certain which of the output lugs is supposed to be ground. And even then, they might not be chassis ground. Grounding a point that is not supposed to be grounded can result in a trip to intensive care for your amp.
I agree with some of the other posters: either both channels are playing the CD’s left track, or both are playing the right track. The “some instruments are in the background” is a classic symptom of this.
For the ultimate in stereo separation, play the Ramones’ first album. The bass guitar was recorded on the left channel only, and the rhythm guitar was recorded on the right channel only. (Or is it the other way around? I forget.)