Kenwood KA-907 amplifier problems

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Hi,
I have a Kenwood KA-907 amp that has recently developed problems
(seemingly unrelated). First off, one channel (I believe it's the right
if I hooked it up correctly) has been cutting in and out and never
works at all unless the DC Coupling switch is thrown. The second
problem appears to be a mechanical problem with the on/off switch. For
a while, the off position wouldn't turn the amp totally off. I would
get no output but the power indicator light would be on. Now the switch
will physically not move down. This has all happened while the amp was
stationary and actually used rather rarely. My question is: are these
problems easily repairable and if so by who?

Additionally I'm running it through JBL L112 speakers which are killing
but the foam of the woofers of which is rapidly deteriorating (how's
that for syntax?). I've done some Googling which seems to suggest
replacing the foam might be more trouble than it's worth (I'm not
helpless with such repairs but I'm not exactly handy either). Do any
experts have opinions on whether it's worth it? If not, what are some
comparable modern speakers?

Thanks!

-Adam

[Mark D. Zacharias]

wrote:
> Hi,
> I have a Kenwood KA-907 amp that has recently developed problems
> (seemingly unrelated). First off, one channel (I believe it's the
> right if I hooked it up correctly) has been cutting in and out and
> never works at all unless the DC Coupling switch is thrown. The second
> problem appears to be a mechanical problem with the on/off switch. For
> a while, the off position wouldn't turn the amp totally off. I would
> get no output but the power indicator light would be on. Now the
> switch will physically not move down. This has all happened while the
> amp was stationary and actually used rather rarely. My question is:
> are these problems easily repairable and if so by who?
>
> Additionally I'm running it through JBL L112 speakers which are
> killing but the foam of the woofers of which is rapidly deteriorating
> (how's that for syntax?). I've done some Googling which seems to
> suggest replacing the foam might be more trouble than it's worth (I'm
> not helpless with such repairs but I'm not exactly handy either). Do
> any experts have opinions on whether it's worth it? If not, what are
> some comparable modern speakers?
>
> Thanks!
>
> -Adam

Sounds like fairly routine maintenance for a tech type. If you aren't
qualified however, you should stay out of it - especially the power switch.
Having said that, sounds like the power switch has a physical lubrication
problem, the DC coupling switch needs contacts cleaned / lubed. If this is
the case, there are likely other switches in this unit that could also
benefit from cleaning.

Mark Z.