Arfa Daily wrote in message
...
"N Cook" wrote in message
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Ron(UK) wrote in message
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N Cook wrote:
Has anyone tried it, for high power testing without blowing a speaker
?
Perhaps tying one speaker enclosure over the one under test with a
microphone midway to monitor standing wave.
Same generator feeding both but adjusting power and phase by some
means
to
the added one to cancel a lot of the overall noise in a confined
space.
--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
I don't really understand what you are trying to do here, are you
trying
to generate an antiphase signal to cancel out the sound from the
speaker
under test?
Ron(UK)
Giving the speaker, under test, with a thorough work-out in the workshop
without driving youself nuts and any neighbours.
Or even testing out an amp with a speaker rather than a dummy load if
there
is likely to be reactance/oscillation problems at high level say.
You do have some interesting problems and potential solutions !! I've
never
had a problem running an amp into a dummy for high power testing. I built
myself one a long time back. I incorporated a power meter, a small speaker
with a volume control to monitor with, a pass-through jack so that you can
go on out to a speaker, but keep the power meter section connected, a BNC
output for a 'scope, and a fall back impedance switching system, with
bright
LED indicators. If I do want to test into a speaker, I have a piece of
thick
high density foam on which I place the cabinet face down, on a concrete
floor. You can then run that fairly hard, without kicking up too much
noise.
Arfa
Foam directly between floor and face of speaker with no extra air volume for
the moved air to compress into at very high power levels and for extended
time. ?
I would have thought that was a definite no-no or are you just doing so, for
no more than 10 seconds say. ?
I tie an old folded up duvet to the front of the cabinet for low to medium
power but I've never dared to turn up the wick to full like that with just a
cone's worth of volume to compress into.
--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/