Not manufactured any more.

1984 guys... Mr Bass himself Brian Cheney of VMPS. I would love to bring back the 3 models I listed and 2 sizes of Bass columns, servo and non-servo.

I have a system that is pretty good direct coupled to 12K class ds. Well controlled bass system for the money.. 20-700hz flat as an arrow, by changing 2 of the 12 driver in the SATs. I'll hunt up some pics.. The short stack in on my Virtual Page.

I use First Watts Active OB XO it has a 40hz step baffle of 3, 6 or +12db (?)..

Regards

A few of the less seen versions pictured here, and a home project version a few years back. Where the Dr. Von Heil Air Motion Transformer (AMT) all started from here in Sacramento California. Fun thread, great memories digging these up. :)

ESS AMT1A (early model)

ESS AMT3 Rock Monitor

ESS AMT6 Professional Series

ESS AMT Monitors (late model) 80s

ESS Transar ATD

ESS Transar ATD

DEC-AMT28 my own custom version in 2018

Very interesting and many I have never heard of. Great to see these. 

When Jim Winey brought out Magnepan speakers it made most of these electrostatic and hybrids obsolete.

This is because that, while being more accurate than cones and boxes alone, they are shrill and cause listening fatigue after a short time. They are also prone to blowing out--try an early Phase Linear on them at any volume--and they are expensive and difficult to repair (I did it in my shop--not easy).

For contrast, my 1975 Tympani I-C speakers sound just as good today as they did when new, and I have NEVER had any issues with them at all no matter HOW LOUDLY or softly I play them with very good electronics, which are required for accurate speakers.

They were fun when new, and certainly helped lead the way to Maggies, but they did not make the long haul.  If I am not mistaken, Magnepan is still in business and innovating every year.  Try them IN YOUR ROOM and see for yourself.

Cheers!

decooney, nice work.. I like it. My hands got sore just thinking about the work.. :-)

Regards