AT what freq does the preamps boosts the high,low,mids in the stingray and highs and lows in the Aguilar pre amp in spectors?
It's not usually a single frequency on an on-board preamp. It is usually a whole bunch of frequencies at once.
The Aguilar 2 band boosts at 40Hz on the bass and 4kHz on the treble. Music Man, OTOH, is a mystery. I asked EB a couple of times when I was working music retail at an EB dealer. They never gave me a a solid or straight answer, which means they might not want anyone to know. I'm sure the terminally curious could bench-test one to get the 411, though.