re: Radio or speaker problem

[Phil Rose <pjrose@servtech.com>]

>Date: Thu, 30 Jul 1998 20:33:18 -0400
>From: Mike Arman <armanmik@n-jcenter.com>
>Subject: Radio or speaker problem
>

>This noise is called "motorboating" and usually appears when one of the
>power supply filter capacitors has gone open. This applies to AC-line
>powered radios, and I don't know what's inside the Bose - it might have an
>inverter and some rectifiers if anything in the radio needs more than 12
>volts.
>
>It isn't a speaker problem - sounds like a bad power amp chip if it is on
>one side or one end of the car only, but if it is everywhere, it's the
>power supply.
>
>Upgrade time . . . (boo!)

Mike,
Yes, "motorboating" is exactly the word I thought to use in my original
post. You say "it isn't a speaker problem", but do you mean to rule out (as
the problem) the amplifiers that are built into each speaker? If so, why?

Anyway, the noise is localized to the rear, but I haven't been able to tell
yet if one or both sides are thundering (being at such low frequencies, it
is hard to pinpoint the source 'till I disconnect some things).

BTW, I'm on record as being among the undiscriminating few who are
reasonably satisfied with the OEM sound (gasp!) So I really don't welcome
the thought of going through an "upgrade", although I have no doubt that
the sound would be improved. (I'd rather see the upgrade money go into
Eurolights or a chip).

Phil

Phil Rose		Rochester, NY
'89 100
'91 200q		pjrose@servtech.com