Thank you Chris,
The electronic crossover with fixed settings shows Roy is not driving the bus. He knows what functions are needed. Most likely the settings are from the testing chamber. Selling fixed simplifies initial setup. Luckily there are software solutions to address this.
I was shocked seeing a screen shot of settings used in someone’s Jubilee system. Seeing +20dB boost at 20Hz is scary. Luckily there is not much music that has content in that frequency range.
I learned this the hard way 40 years ago. Friend worked at the Country Music Hall of Fame. Was recording some of the 78’s from the early days. Said one issue was no standard for playback EQ then. Had to play flat, then adjusted to find an EQ curve that fit what was on discs. Used a signal generator to test the curves to see where the poles were.
Gave me an idea. My Altecs were far from flat. Used signal generator and scopes at work. and had an unused graphic equalizer. Borrowed a microphone and preamp that was “flat”. Extended frequency range.
Ran some room sweeps. Then made adjustments. Then more sweeps. Watched until the response looked okay, not flat but better than unequalized. Huge bottom boost. Neighbor lived like a 100 feet away. Asked me what I was doing, his windows were rattling.
Played a few records. The results were okay, the graphic equalizer had a high noise floor, never used it, was in tape loop.
Thought maybe I just needed to crank it up. Get some real volume going. Heard the woofers crack and voice coils start rubbing.
Had to fight with Altec in OKC for replacements, Got them down to 250 each. That was a lot in the early 80’s.
Put the equalizer back in the closet, for good. Those old 15’s in the Altecs were like 30 watts. Did not take long to break them with huge bass boost.
Never used bass boost since. That is why they make subwoofers,
