I had never built an electronic crossover (EXover) before
but do understand how they work. This EXover would be simple as it was to just work
with stereo sub-woofers and reject frequencies above 60Hz. The single cct. brd.
contains the differential PS required to power the LM833 OPAMPs left over from
other projects. Due to the fact that this EXover was as simple as an OPAMP
preamp a single cct. brd. solution was easy.
The cct. brd. is vero-board or strip board and fitted into a
standard enclosure I use for headphone amps. The input\output RCAs were mounted
on the top of the enclosure and power socket on the rear. A small ex-power
drill charger suppliers 18V @ 400mA for the EXover which only requires a very
small amount of current. As stated above
this is converted to +\- 9V by the power supply on the cct. brd.
The design was meant to produce a rollover at 60Hz but under
test the rollover occurs at 52Hz. The slope is only -12db\octave. This gentle
roll-off allows lower mid frequencies into the sub-woofers drivers but also
allows for easy integration into my 2-ways speakers. The EXover performs well
with inexpensive parts and is dead quiet in operation.
