Rerurn to Romy the Cat's Site

Congratulations, Romy, I think you just re-invented the ISOBARIK loudspeaker.

Although, Linn's Isobarik implementation of two drivers moving in parallel separated in a small chamber which would be nearly in constant volume (and pressure) couldn't really work as the trademarked name implied it was an interesting point of departure.

At one time, I thought to take the idea of using an internal self-contained loudspeaker to keep a constant volume/pressure chamber as way of  "killing two birds with one stone."

It would allow the primary driver to work nearly at free-air resonance but in a smaller enclosure. The price of inefficiency would be paid by the internal driver and efficient amp. A servomechanism would maintain the constant internal pressure. A servo would work well here as it would be homeostatic and not a motional feedback system where the linearity and phase of the servo would be critical. It would also not be in the signal path of the primary driver.

The second advantage would be to isolate the external cabinet from the high pressures which cause the panels to radiate. I also suspect that high internal cabinet pressures (i.e. both high and low pressure extremes) cause speaker cone bending different from that caused by the driving voicecoil and suspension. Avoiding this cone-bending/shape-distortion gives, I suspect, an advantage to high volume or infinite baffle woofers - an ease to their sound.

In somewhat picturesque terms, think of your highly regarded Aura 1808 driver in a modest non-vibrating enclosure operating at free-air resonance. An internal speaker such as small ContraBass Servomotor Driven Subwoofer (which uses a radial motor instead of a linear motor and is capable of formidable excursion) would be used to maintain the constant internal pressure.

I now live in a home with an attic and basement, either of which I might use for an infinite baffle woofer. This has made my earlier idea unnecessary for me personally.

Regards to all,
Robert

P.S.  Markus's post and Romy's reply came while I was writing this.

Rerurn to Romy the Cat's Site