(incept date 2025.06)
Preface
I’ve retired from doing live sound gigs, but I still get asked to provide sound for smaller dance events a few times a year. I use a nicely portable Yamaha PAS-400 PA for the small gigs, but the medium sized ones have involved hauling around too much large and heavy gear.
According to legend, the Bose pro-line 800 series were originally prototyped using turned-around 901’s. As I have a spare set of 901’s laying around, I thought I’d see how well a pair 901’s would work for the medium sized venues. (A bonus is they are effectively mini monitors for the dancers to hear better.)
The initial concept is to see how well a dbx drive rack PA2 can be used to effectively replace the Bose processor box. The extra headroom of the pro level +4 dbV signal path will be helpful here, especially when fed to the QSC PLX 3102 (rated at 600 watts/chn) amp I have.
This experiment will first quantify the speaker itself to generate the speaker “flatten” parametric curve. Unlike the home use EQ, I’ll be separating the speaker EQ from the Bose house curve, as that curve is likely wrong for PA use.
I plan to use the dbx output PEQ (+/- 20dB parametric) to first cut/flatten that large midrange hump, then use the Auto PEQ to trim up the overall in-room frequency response. That leaves the GEQ (+/- 12dB GEQ for touchups and applying a PA house curve.
Also, I’ll crossover to subwoofer at 80 Hz or so, as distortion in the 901 speaker goes up rapidly below that point and the dbx subharmonic synth would bottom out the 901 cones far too easily anyways.
Other experiments include adding a linaeum tweeter, and evaluating suitability as L/R fronts in a 5.1 system with a Bose 101 as a center speaker.
2025.09
I got sidetracked by some health issues for a while, but I’m back now.
I investigated using 901s turned around make a great “small and wide room” PA, i.e. when the speakers are rather far apart compared to the throw to to the audience. In my case, the speakers are about 20 feet apart, but only 6 feet to the first row of ears. The broad horizontal dispersion works very nicely here, still yielding a pleasant stereo image without completely blasting the front row. Sweet.
Last Updated on 2025-09-09 by Daev Roehr