Help Please - Crackling in One Channel

[krevans]

Can anyone give me an idea why such a fine unit as the NAD 3150 would be crackling in one channel? Sometimes it cuts out entirely, and I can get it back by increasing the volume. I've cleaned and lubed the volume potentiometer, but it still comes back.

The crackling is intermittent, but seems to come out more with heavier bass.

Thanks,

Ken

[RGA]

Does it happen out of both speakers? If only one speaker switch the two speakers. So if the crackle comes out the left channel and you switch and the crackle is coming out the same speaker then it's a speaker issue. Try and make sure where the trouble actually is. Check your speaker wires...are they bare wire...are they all connected and not oxidized?

It could be a capacitor etc. Amps do often require servicing around the 15-20 year mark.

[krevans]

I checked the speakers and their connections, switched them, etc. It's a problem with the amp. The crackle comes from the left channel only. It can disappear for a while - or at least become imperceptable - but can come back during a low-bass music passage. I don't hear the crackling in headphones.

[RGA]

I checked the speakers and their connections, switched them, etc. It's a problem with the amp. The crackle comes from the left channel only. It can disappear for a while - or at least become imperceptable - but can come back during a low-bass music passage. I don't hear the crackling in headphones.

That's frustrating...Unfortunately you'll probably have to take it in for a check, because it's intermittant and more noticeable on low frequencies.

Sorry I can't help, I'm surprised the engineers on the board have not been answering the post.

I would try your post at http://www.audioasylum.com/forums/amp/bbs.html You don't need to register but there are more technical folks over there.

It's more of a high end forum than this mid-low fi forum as well.

[300A]

Krevans, first check out Interconnects for intermittents. Then any other connections/wires.

If problem is the amp, either broken or intermittent solder connections around the input/speaker jacks, switches, controls (usually stress related) or heat sources on the PC board, around hot resistors or SS devices;

or a part, usually a transistor, is intermittent.

Either of these would require a tech to service.

[Kursun]

Does the crackling sound come or increase when you touch and turn the volume, or any other control, switch? If so that control (volume pontentiometer) has to be replaced. I believe NADs also have problems with their time-delay relays (the relay that mutes the speakers for the first 3-5 seconds so the voltages inside the internal circuitry stabilizes).