Re: Marantz P400 cuts out at low volume



nathan_conder@xxxxxxxxxxx wrote:

Hi,
also not tubes (although i do dabble in the valve DIY) but perhaps
worthy still. please help

managed to pick this great amp up for free (with full system) but it
has started to play up.

one and sometimes both channels fuz and cut out itermitantly. It
seems to be worse at low volume settings and will usually cut in
during peaks such as kick drum beats or when the vocals start. my
best bet is perhaps a capacitor in the power amp stage has failed but
which one?

i have checked for dry joints as best i can and there also does not
seem to be any speaker protection relays that may be playing up.

any help?

Carefully re-solder all the joints you see in the set, and retry.
Sounds like a dry joint, and why you got the item for free.

So you can afford to take it to a tech, or afford to put up with some
long tedious and possibly silly advice here.

Maybe you can learn what we know, and fix it yourself,
but typical faults with old SS gear take some time to get used to, and
so be careful you don't fully stuff up the item in your attempts to fix
it
without any experience.

Got a full workshop manual with all schematics?

Patrick Turner.
.

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