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[audio] dumb ohm-age question (or square peg & round hole)



well...

[electronics technician hat]

coils - in series - allow bass to pass (as opposed to trebble) - called a
low-pass filter
the coil is an inductor, which opposes rapid changes in current. slow
changes (bass) can make it through.

caps - in series - allow trebble to pass (as opposed to bass) - called a
low-pass filter
the capacitor opposes rapid changes in voltage, thus acting like a short to
rapid changes, which results in those rapid changes (trebble) being passed
on to the speaker. slow changes (bass) only result in the capacitor rapidly
charging/discharging, therefore absorbing the bass. another note here is
that its important to NEVER use electrolytic caps for this purpose, as they
are polarity-based (where sound goes both + and -).

both of these methods are safe because in both cases, the filter prevents
the signal from getting to the speaker. there are also such things as
capacitor-high-pass and indictor-low-pass filters, but these filters are in
parallel with the input (from the amp), effectively shorting it out to cause
the filter action. so... ALWAYS use the filters IN SERIES with the load
(speaker), or you risk total destriction of the amplifier.

[/important safety tip]

HTH
Allyn Malventano, ETC(SS), USN - who teaches crap like this every day :)