Re: High Frequency Compression Driver Evaluation
Greg,
Back in the "olden days" we used RTA for measurement, I only saved a few printouts, but there were differences in both cones and HF drivers, some from the factory, some over time from road use and abuse.
I have a lot of Eminence Alpha 8A and Lab 12 cones, they all measure remarkably consistent (within 1 dB) regardless of age purchased.
The Eminence PSD2002 and APT tweeters are not as consistent, with unit to unit variations of more than 3 dB.
When designing passive crossovers for those drivers, I have had to use an average between units.
To reach more consistency I matched and numbered the four pairs of APT tweeters used in my stage monitors, that way at least each pair will work together with one EQ.
Art
