I wonder if a typical plate amp could use a dirtied up tube input stage to flood the amp with 2nd harmonic distortion for this.Taking aside the 2nd harmonic cancellation of the sub box/driver design what if you power said sub design that has a amplifier power source that is maybe designed deliberately to re-inforce said 2nd order harmonics? Does this give you the perfect sub?
I'm in the middle of completing some folded open baffle bass bins/speaker stands.
Maybe while waiting for the last parts' delivery, I'll dig out a tube buffer and insert it to line level feed the plate amp.
is this the ‘harmonics’ ?(example)
(Fb)300cm - 28.8 hz
2Fb (150cm ) - 57.6 hz
3Fb (100cm) - 86.4hz
4 Fb (75cm) - 115.2hz
5 Fb(60cm) -144hz
(Fb)300cm - 28.8 hz
2Fb (150cm ) - 57.6 hz
3Fb (100cm) - 86.4hz
4 Fb (75cm) - 115.2hz
5 Fb(60cm) -144hz