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"Todd Carney" wrote in message ...
Folks,

I've Googled until I was blue in the face about this problem, and a
few times came close, but no cigar!

My problem:

1. I have an Aiwa receiver that came with two-way speakers and has
only two-way speaker connections--"low" and "high."
2. There are no one-way connections at all.
3. BUT, I want to have a couple of sets of remote speakers that I'd
switch to on demand.
4. I know how to do the switching, so I covered there.
5. I already have those speakers, and they are all one-way.
6. SO, my problem is how to recombine the "high" and "low" speaker
outputs and then switch them to the remotes.

7. I DON'T know how to safely combine the receiver speaker output.

A few details:

1. According to its manual, each frequency range has its own
amplifier.
2. I have no idea how isolated (or not) the amps are. I don't know if
they share a common return or not.
3. The unit has speaker outputs for "surround" sound. They are one-
way. I will not be using these.

Here's the solution I've come up with using my woefully-inadequate
savvy. Please see my sketch drawing here (Google Docs with shortened
URL): http://bit.ly/mRxzgB.

What do you all think? Will this work? Is it safe for the amps?

Many thanks! ---Todd

https://docs.google.com/document/d/1.../edit?hl=en_US

Todd, that won't work. Although the amps are isolated with respect to DC, they are not with respect to AC. The
amps' feedback circuits will see each other's signal as an error, and one or both amps will blow themselves up
trying to correct that error.

You're going to need a separate stereo amplifier to feed the remote speakers. There are several ways to
get a full range signal to drive that amp; the best would be to tap into the line level signal inside the Aiwa, ahead
of the crossover circuitry that's feeding the Aiwa's amps, and bring that signal out via a pair of jacks to feed
the remote amp. How difficult this would be to do depends on the circuitry in the Aiwa. You would first need
to find a schematic of the Aiwa and then go from there. It could be necessary to add an op-amp to the input
of your remote amp for some extra gain if the signal levels in the Aiwa are too low to drive the remote amp to
the levels you need.

Good luck

Fred