I measured the output of SA-2 while I routed Pro Tools Signal Generator to its input. Watching the gain reduction meters deflect downward to maximum as I finely "tuned" the sine wave frequency coming into each of the five sections, I could determined the center frequency of each of the five bands. Of course there is overlap so I muted all other bands except the one I was measuring.

The center frequency of the each of the band I measured are: Band 1 is 3kHz; Band 2 is 5kHz; Band 3 is 7kHz; Band 4 is 9kHz; and Band 5 at 11kHz. Each of the five bands has its own gain reduction meter that will indicate up to 12dB of gain reduction. By pushing more level into the plug-in using the input fader, I was able to get more activity on any of the bands--but under normal operation, this is not necessary.

SA-2 has a couple of settings that govern how strong or gentle the processing is. The top Mode control selects between three different combinations of compression ratio, attack and release times named: Assault, Normal and Gentle. As named, these set the amount and character of compression. Below the Mode switch is the Band Mode button to select (globally) the bandwidth of frequencies (Q of the filters) covered by each of the five bands. They are Narrow, Normal, Wide and Vari or Variable--proportionate Q--the deeper the processing the narrower the bandwidth of the filter becomes.

I had great fun trying SA-2 on vocals--where it is an excellent and nearly transparent de-esser because of the five frequency bands available are useful to 'zero in' on the frequencies of most energy. It also worked well for drum overheads for taming overly loud cymbals or any overly shrill and bright source that just needed mellowing out. I would mute or bypass individual sections to strike a compromise between over-dulling the sound and adequate and musical control. Awesome!