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Chamberlin | 25-35-45 Rhythmate


The first sample-based drum machine, the Rhythmate was invented by Harry Chamberlin in 1949. Chamberlin recorded 16 acoustic drum patterns to individual 1-inch tape loops. The Rhythmate user can choose between the loops with a slider or can mix two adjacent loops together by placing the slider between them. Pair it with an organ, and you’re ready to soundtrack a boardwalk amusement park or a ‘60s Holiday Inn cocktail lounge.

If the Rhythmate’s tape-playback mechanism seems reminiscent of the Mellotron—the keyboard famously used by the Beatles, The Moody Blues, and countless others to play pre-recorded strings, flutes, and choral tones—that’s because Chamberlin was the inventor behind the Mellotron as well.

Chamberlin brand keyboards were a sensation at NAMM in 1956, but reached greater fame under the Mellotron name after a Chamberlin salesman stole the original patents and sold the idea as his own to a UK company. Chamberlin worked out a deal with the UK-based Mellotronics, enjoying payments from that firm as well as the growing popularity of his Chamberlin products.

Though he had made fewer than 10 Rhythmates originally, Chamberlin capitalized on his newfound success, tweaking the idea and manufacturing various versions of his drum machine during the '60s, though it is believed he never produced more than 100 total.

Model25-35-45 Rhythmate
Engine TypeAnalog
Extra info10+ made
Produced:1960 - 1969
Legend: Obvious Y: Yes, N: No, N/A: Not Applicable
VCO Voltage Controlled Oscillator DCO Digital Controlled Oscillator
LFO Low Frequency Oscillator Sub Sub Oscillator
VCF Voltage Controlled Filter VCA Voltage Controlled Amplifier
Velocity As with a piano, the harder you hit a key, the louder the sound, unlike most organs which always produce the same loudness no matter how hard you hit a key. Aftertouch Pressing a key after you activated it. Channel Aftertouch, no matter which key, it will send a Channel message. Poly Aftertouch, sends the pressure per key instead of the whole channel.
Values for OSC, LFO, Filter, Envelope are per voice unless stated otherwise.

Manuals, patches etc.


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