Acoustat Monitor 4 Speakers

Acoustat Monitor 4 Full Range Electrostatic Speaker
System

These beautiful, majestic, and rare speakers where manufactured by the Acoustat
Corporation, Ft. Lauderdale, FL circa 1980. 
Any fan of electrostatic speakers would appreciate the sound of these
speakers.  The larger 4-panel
configuration delivers a good bottom end often lacking on narrower di-pole
radiator designs. The Monitors stand just over 5 feet tall and 3 feet wide.

Includes two MK-121 Magne-Kinetic power supplies. (serial
numbers 201111 and 201112) to allow the Monitors to be driven by a standard
power amplifier.

The retail price according to 1979 Edition of Indian River
Life Magazine was $3000.

Known History of these speakers:

In 1987 while I worked at the Sound Gallery in Melbourne, FL
the previous owner brought these speakers in to have the Red Medallion
Transformer upgrade to the MK-121s from version A to the C.  I performed the upgrade.

Mid 1990s – I auditioned and purchased the speakers.

2014 – One MK121 exhibited reduce output.  A measurement of the 5kV supply indicated R5
(500M ohm, 15%) resistor was open.  R5
on both units were replaced with 100M ohm, 1%, 10kV thick film resistors.   A lower resistance was selected for faster,
more stable, charging of the panels.

The MK-121 power cords were showing signs of age.  These were replaced by 14 foot cords of
larger gauge.

Electrically and acoustically the speakers are in excellent
condition.  They still sound as
beautiful as any full range electrostatic speaker.   However, the speaker fabric is natural burlap and is
deteriorating and fragile.  Realize
these speakers are more than 35 years old. 
Great care must be taken when handling. 

Due to the size and delicate nature, these speakers will not
be shipped.

Accessories Included

• Night lights – two picture frame lights that sit on top of
  panels that softly illuminate the speakers.


• 15kV High voltage probe with carry case (for
  testing/troubleshooting power supply)


• 1979 Edition of Indian River Life Magazine Featuring the
  Acoustat Monitors.


• Related Manuals, MK121 schematics in electronic form found
  on the internet.


• Cover cloth – same color as grill cloth for covering
  acoustic absorption panels that sit behind the Acoustats.  (absorption panels not included)



• Bumper Sticker “Have you hugged your Acoustats
  today?”

Contact Info:

Located in Rockledge, FL

For more information/pictures: [email protected]