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Can you help with this problem?

Audiogoners can you help a friend who has the following problem.

Here's my set-up:
NAD 304 amplifier
NAD 514 CD player
Energy bookshelf speakers
Decent high-end cables... don't know the brand because I bought them
used from a stereo shop that was remodelling, but they are supposed to
be better than Monster.

I have a turntable, cassette player and mini-disc as well, but those
are the components involved in the problem.

Every so often, my left speaker will start to "sputter" and sort of
"fuzz out". I used to have the same problem with an entirely different
system (big, honkin' 1970s model Sony amp, Bose 901 speakers). I know
it's not the speaker cause I've swapped them over, and it doesn't seem
to be the connections at either the speaker or amp ends.
The only consistent thing I can tell you about it is that it often does
it with certain bass players... Charlie Haden will often cause it to
happen.
Is this something to do with the amount of power being put out to the
speakers, the frequency of the music or what?

Needless to say, it never happens when you want it to, so it's really
difficult to get anyone else to hear it.

TIA

Ben
ben_campbell
rar1's avatar
rar1
1,769 posts
 
Ben:

Another place to look and it is a long shot, but it has happened to me. Does the cutting out situation occur when you are either:
1. increasing the playback volume and/or
2. the frequency of the music being played is causing the speaker cables to vibrate/move.

If this is the case ... the exposed portion of the speaker wire leads may be touching each other and causing a momentary cut-out (the amp's speaker protection circuitry is kicking in). For me, it was the Left & Right sides of the same speaker cable touching each other.

I still shake my head ... but it happened to me. I would check for this before I started to clean the unit.

Regards, Rich
zaikesman
3,017 posts
 
Ben - You say it's not the speakers because you've 'swapped them over'. If this means that you physically moved the speakers each to the other side and the problem remained on the left, then you are correct. But if this means that you only swapped the speaker connections left for right at the amplifier end, and the problem remained on the left side, then the left speaker could still be your culprit (likely a fault in the LF driver, its crossover, or its connections).

But if you did in fact rule out the speakers (and speaker cables, tested separately) by physically swapping them side for side, then the CD player, its interconnects, or its assigned amp inputs would be suspect, since you imply that your other sources do not show the same problem, and these possibilities could be tested for by likewise performing separate channel swaps or gear substitutions for each.

But there is another remote possibility: the player's output could simply be just a bit too "hot" for the amp's input stage to handle cleanly on certain LF peaks, and these may be channel-specific in the program material. The only reason I characterize this possibility as unlikely is not because it doesn't ever happen (I've experienced it myself, though it affected both channels equally), but rather because your player and amp are both made by the same manufacturer, and should not exhibit this degree of incompatability.
ben_campbell OP
1,169 posts
 
Guys thanks for the replies,if you read my original post you'll see the set up is not mine.
I posted the exact wording my friend stated-I'll direct him here and let him add more info or I'll post his reaction/findings.Thanks again.
tubular_joe
3 posts
 
Ben-It does sound like poor switch or pot (control) contact(s). A bass note requires more current to pass successfully, and making sure all of them are clean is the ticket. I recommend LPS 1 spray. A light shot will do, then work the pot or switch a bit. It is not organic, therefore non-ionic, and does not attract dust and impurities. It helps lubricate, like other sprays, but will not damage deposited carbon elements in pots as oil and silicon-based sprays might. To go a step further, there is a special spray available for pots made by Cramolin, which is even better for them.
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