Selecting drivers is an art more than a science,
although it uses some science. I selected drivers by picking from
spec sheets, and knowing manufacturers. I first picked the Vifa
PL18WO-09 and the LPG 38T.
I picked the Vifa because the specs on it are virtually
perfect for a monitor. Good high end, great power handling, and
adequate bottom end. It's a bit bigger than usual for a smaller
speaker but the above average high end works well in this design.
I picked the LPG because I wanted a larger-than-usual
tweeter to allow for better power handling and to simplify the crossover
If you've read the earlier pages you will note that
the original testing knocked the LPG out of contention. Measurements
were so-so and listening tests were similarly so-so. I originally
switched to the Vifa D27 (a tweeter I've used before) but when my
driver supplier (AudioLab of Georgia) got in the Vifa XT25 I tested
it as well and ended up using that tweeter.
So, the final driver complement in the monitors is
2 Vifa PL18WO-09 and 1 Vifa XT25TG-30. The drivers alone cost approximately
$180 per speaker. These are the high-end drivers from Vifa. The
middle-class Vifa drivers would cost about $60 per speaker and work
just about as well (with a bit less bottom end and a bit hairier
To make this simpler to read/understand all of the
discussion in this section assumes the final driver complement and
ignores the mistakes / retries (those are written in earlier pages).