Articles / Gear

RCA Theremin and Replica Speaker To Be Auctioned November 22nd

RCA Theremin

Here is a rare opportunity to own an authentic, working and fully functional RCA Theremin!

Update - The auction is now live on eBay!

This historic instrument was part of the world-famous Milhous Collection, the only such instrument in that treasure-trove of rare and one-of-a-kind musical and mechanical artifacts.  It is RCA serial number 100065 -- the 65th unit to come from the General Electric production facility in Schenectady, New York in the fall/winter of 1929.  The original price of this instrument with vacuum tubes and speaker in 1929 was $232, the equivalent of more than $3000 today.

The electronic design of the RCA theremin was engineered by the inventor himself, Leon Theremin, and to this day remains the only manufactured theremin produced by any company at any time, that is of his own design.  It employs Theremin's signature arrangement of type 27 pitch oscillator tubes, working into a type 24A mixer; the same pitch oscillator circuitry as Clara Rockmore's famous custom-built theremin.

As noted above, this instrument is fully operational, and has the classic RCA theremin tone that more modern theremins can only attempt to emulate.  It retains nearly all of its original 1929 components, including the main instrument chassis and power supply chassis (not a Radiola replacement as is sometimes seen).

Nearly all of the often-missing parts are there and are original to this instrument:  Both antennas, the music shelf, the pilot lamp cylinder and jewel, the "Volume" and "Pitch" plates under the control panel, and the original set of "On / Off" and "Play / Off" toggle-switch escutcheons.  The control knobs are original. Both of the RCA tall resonance coils are in place and intact, comprising close to 2000 turns of incredibly fine, silk-covered wire.

The cabinet, which at one time had been painted a cream color, has been restored and refinished, with new doors.  A mid-height perimeter trim detail and internal stabilizing blocks were added as part of the cabinet restoration.  One defective switch has been replaced for reliability. The wiring harness has been augmented with a Jones-type plug to facilitate convenient removal and installation of the power supply and main theremin chassis.

Of particular interest is the speaker stand and speaker, both are rare contemporary units made in a very limited production.  The speaker stand was made by master craftsman and custom instrument maker Floyd Engels.  The stand, from its hardwood base to its diamond baffle and authentic-pattern woven grille is a stunning copy of Clara Rockmore's vintage diamond speaker, made from actual measurements taken directly from that unique survivor.

There are two features of this craftsman-built speaker stand that increase its adaptability, giving the buyer additional options for display and use:

* The back of the speaker baffle is drilled with an alternate set of accurately positioned mounting bracket holes, giving the owner a choice of the dramatic original 93" height (utilizing its full complement of four supporting members), or the convenience of an approximately four foot height using just two supports.

* The baffle panel is also drilled with four mounting holes perfectly positioned to accommodate a vintage RCA 106 dynamic speaker should the owner wish to play the theremin with that unit, which was RCA's recommended speaker for the instrument in 1929.

The speaker driver currently installed on the stand is one of less than ten "Claratone" speakers that were custom made by Weber Vintage Speakers.  It was designed to be a perfect complement to the RCA theremin triode audio output circuit.  The Claratone speaker is extremely sensitive, utilizing an expertly engineered combination of heavy ceramic magnet, lightweight cone and micro-gap voice coil.  The theremin comes with a Hammond audio transformer that perfectly matches the original amplifier's output to the Claratone speaker.

Other noteworthy details: The paint on the chassis and power supply is original.  The RCA inspector's hand-written marks remain intact on the audio transformer.  The power supply has an original 1929 style type UX-280 tube with the classic balloon shape and engraved Bakelite base.  Likewise, the pitch oscillator and mixer tubes are of the early ca. 1929 style. 

The power cord is an authentic reproduction, with braided bronze fabric.  Finally, this theremin has an original, factory-installed resistor on the mixer tube grid cap for enhanced tone quality -- a known RCA improvement that is seen on only some of the original production.

RCA Theremins seldom come up for sale in any condition. The relative few that survive are in prominent collections and notable museums around the world, and not all of these are in restored or working condition.  Don't miss this chance to obtain a truly rare and fully functional, working historic RCA theremin, that you can proudly display and play.

As soon as the auction is live, we will update this post with a link to the sale.  In the meantime, you can see several more pictures of the instrument and speaker in our photo gallery.