In article ,
wrote:
You can use speaker volume controls. It's better and easier if you used
100V speakers - multi channels of 100V speaker level audio were carried
on a multicore cable to passive bedhead units with a vol control (multi
tap attenuator) and channel selector in hotels and hospitals - but you
could do it with low impedance (8 ohm) audio. The drawback with low imp
is that adjusting one speaker can affect the others.

100v line may be convenient for some things, but is never better. Decent
transformers ain't cheap. Maybe OK is just using very efficient speakers -
but most would be considering ordinary domestic speakers of one sort or
another.
Other thing is with less than perfect speakers, an individual amp can
apply bass boost etc to help them along, as well as setting the volume.
With one amp and 100v line, you could only do this if all the speakers are
the same.

If you want to distribute at line level and have local amps then you
could also distribute say a 24 volt power feed along with the signal
wires.

Beauty of my system is being able to use cheap and small cable. Running
enough low volt DC for a power amp would require heavier cable. And is
getting complicated.

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*IF YOU TRY TO FAIL, AND SUCCEED, WHICH HAVE YOU DONE?

Dave Plowman London SW
To e-mail, change noise into sound.