Keppinger Vacuum Tube Theremin FS

Posted: 10/6/2008 7:42:14 PM

From: Boulder, Colorado

Joined: 8/17/2005

I am preparing to sell my Keppinger theremin.

Keppinger's photo page here:

Photos of my Keppinger and my RCA (Maunette) here:

My Keppinger has additional external trim pots added by Steven Hasten. This was his personal Keppinger.

Mark Keppinger wrote me the following about his theremin's built:
There were only eight of these fine instruments built. I still have the first one. The second went to the Jon Spencer Blues Explosion. When
word got out, Steven Hasten contacted me, and wanted to be a part of what I was doing. I had parts for six more, and told him that if he
built them for me, he could have one for himself. Naturally, he 'cherry picked' the one that he liked the most, and gave the utmost attention
to it's adjustments. That's the one you have.

So where the others? Well, like I said, I have one. Jon Spencer has one. A collector in Holland has one. A recording studio in Honolulu has
one. The president of a company that does special effects engineering for a large Anaheim corporation (also Florida, France, Japan, etc) has
one. You have one. I'm not sure about the others..."

Any serious offers above $1999 will be considered, else I will place this Keppinger on Ebay. I have a robust custom wooden crate for shipping the Keppinger.

I want to give the Theremin community the first opportunity.

Here are some sound samples of my Keppinger theremin, and my RCA theremin through the same loudspeaker (Low cost 10 inch polypropylene in an infinite baffle), with the same microphone and position (EV-RE20 at about 12 inches from speaker), recorded at 44.1khz, 16bit, converted to mp3 at 190kbps.

When I first powered up my RCA I was surprised to get no sound. I haven't had it on in a few months (shame on me).

I found one of the type 27 tubes not working. I've got a box full of tubes, so I tried several combination of 27 tubes, as these have been noted for changing the timbre of the RCA.

Indeed they do, as evidenced by the R samples.

The Keppinger emits a strong tone within about 45 seconds after power up. It is pitch stable within 3-5 minutes.

Steven Hasten built the Keppinger, and restored the RCA, so he tuned both to his liking. Both are capable of producing pitches above what they are designed to, and when played too high generate birdies (spurious tones). I believe that is a function of how he tuned them, and I have not tried to resolve that. I like the extended range, even if it is with artifacts (they're kinda fun, and start above the normal pitch range).

Sound Samples


There may be some sympathetic vibration heard from various objects in the room as the tone reaches their resonant frequency. I tried to keep that at bay.

Posted: 10/18/2008 10:53:31 PM

Joined: 8/16/2008

Hello Bret,

Please contact me

Posted: 10/19/2008 2:13:59 AM

From: Boulder, Colorado

Joined: 8/17/2005


My Keppinger has been sold.

thank you,
Posted: 10/20/2008 12:55:10 PM

From: Richmond Hill, Georgia

Joined: 9/18/2005


If you have any questions, please post to Levnet, where myself, Mark, and others hang out...or email me at ka4koe at arrl dot net

Philip Neidlinger
Richmond Hill GA

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