Amp channels kick in at slightly different times

Caporegime
Joined
13 May 2003
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Location
Warwickshire
Hi all

My old NAD3040 sounds great and works pretty much perfectly. There's one very minor niggle, which is that the L+R channels kick in at slightly different times when I switch the amp on (the gap is about two seconds).

Is this a sign that I need to open it up and give it a service? Any ideas what might be causing this? If it's something that will develop into something more serious, I'd like to catch it early.

Cheers.
 
Man of Honour
Joined
29 May 2010
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Cheshire
Are you sure this has only just started happening? If so then the most likely culprit is the big power reserve capacitors are drying out and so taking longer to charge.

Replacing these isn't a highly technical task but does involve stripping the amp and then doing some soldering work. The caps are also one of the most expensive components. Like-for-like replacements could be as much as £20~£40 each and you might be replacing 4. On that basis you might decide to live with it until a channel dies, then replace the amp.
 
Caporegime
OP
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13 May 2003
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33,939
Location
Warwickshire
It's happened since I bought it about 5 months ago and I noticed it straight away. The price was low so I might just live with it until it dies like you say.

Wouldn't know where to begin soldering caps etc.

Cheers.
 
Man of Honour
Joined
29 May 2010
Posts
6,351
Location
Cheshire
Right, so you're saying you bought it "as is" and you don't know if it did this from new because you weren't the original owner.

None of the NAD reviews I've ever read have mentioned the amps coming on one channel at a time. But since most of us turn the volume down before powering on then it's possible (though very unlikely) that this could have been missed. However, it's more likely that this is a fault. The only other issue that was common in dual channel amps was that on increasing volume one channel would sound a little sooner than the other, but that was an issue of channel balance at the lowest part of the volume dial where the percentage error is at its highest.

NAD amps - good amps - but when so many are available for very little money then it's hard to argue the economy of recapping.
 
Associate
Joined
23 Nov 2004
Posts
301
I would not worry about it too much. I very much doubt it will develop into anything more serious.

I'll have a look at the circuit in my service manual and see if anything come to mind.

One small correction: a dried out capacitor won't take longer to charge. Its capacitance would have reduced so it will in fact charge quicker.
 
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