Cheap JVC subwoofer mod

Someone was throwing away a JVC SP-PW37-SUB.
After I hooked it up and listened to it I instantly knew why.

It was a sealed design, cheap speaker. Probably part of a theater-in-a-box system.

I found an inexpensive 8" sub on PE, SD215A, that would work great by converting the cabinet to ported.

0.8 cu. ft., tuned to 31Hz, 2" x 9.5" port.

Since I only have stereo output available, and the amp on this unit is for sub-out, I built the summing circuit found here at post #8:

Used the sub amps power supply to feed +/- 12V regulators for the summing circuit.

Sounds much, much, better after the mod. Not sure what the crossover is set for on this unit but it seems to match well with my setup. I had the parts for the summing circuit, so it was well worth the 30 bucks or so that I spent.


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