Original Sequential Circuits Prophet 10 (1016)

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via this VEMIA listing

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VEMIA is Peter Forrest's auction house. He is the author of The A-Z of Analogue Synthesizer Books. Pic of the inside below.

"Vintage Sequential Circuits Prophet 10 Dual Manual Keyboard Synthesizer with Flight Case This Prophet 10 is in very good condition, and is fully functional, although the Braemer tape drive has not been tested. Has factory MIDI and sequencer, and the original blue Prophet-10 flight case on wheels. This may be one of the last Prophet-10s made, as the S/N is 0444. It's big and heavy!! Includes power cord, electronic copies of the operation manual and service information, and one original Sequential footswitch. The flight case foam is serviceable, but could use replacement. The synth is wrapped in plastic within the flight case. Full pictures are here [captured below]. By far the most prevalent of the original Prophet 10 models, the Prophet 10 Rev3 was a better built version than the previous 2 iterations for more consistent and reliable performance. It used Curtis Electronics Manufacturing chips, and featured 2 VCOs per voice, a low pass resonant filter with ADSR, LFO, & cv/gate controls. This rarely seen monster analog synth is by far one of the fattest and nicest vintage synthesizers. The Prophet 10 is in effect two fabulous Prophet 5 synthesizers packaged together, giving 10 voices with 20 of Sequential's unique analog VCO oscillators at 2 per voice for a big fat analog dream! After the first 2 versions of the Prophet 10, finally, in 1980 a reliably working 10-voice, 20-oscillator, double-manual keyboard, Revision 3 Prophet-10 made it into production. One of the largest analog synths available at the time, the Prophet-10 featured much of the same architecture as the Rev. 3 Prophet-5. Like the Prophet-5, each voice consisted of two VCO's (voltage controlled oscillators) and a white noise source, all of which can be mixed into a resonant low-pass VCF (voltage controlled filter). The filter modifies the voice timbre under control of its four-stage envelope generator. The filter may also be resonated and serve as a sound source. Following each filter, a VCA (voltage controlled amplifier), also controlled by a four-stage envelope generator, shapes the voice amplitude. Supplementing the basic voices are polyphonic modulation (POLY-MOD) signal routings within each voice that allow VCO2 and the filter envelope generator to function as modulation sources applied to VCO1 frequency, pulse width, or the filter frequency. Finally, there is a single LFO (low-frequency oscillator) and a pink noise source which can be mixed to modulate all voices, as adjusted by the MOD wheel. All of the voice settings, along with settings for volume and tuning, could be saved and instantly recalled on a total of 32 memory locations (4 banks of 8). The Prophet-10 features two complete sets of program switches with corresponding LEDs that light up to show you which voice is playing. To the right of the program switches are the master volume knobs and tuning aids, including an A-440 tone module, a master tune knob, and the autotune button. To the right of what otherwise looks much like a Prophet-5 front panel is an extra section. Here are the programmable volume and tuning knobs, and switches for routing the input from two available footpedals. Destinations are pitch, cut-off, VCA, or mono modulation. As in the Prophet-5, there is also a release switch. Above the two groups of program control switches are the keyboard mode switches. The two keyboards can be configured to the following modes: * Normal Mode - This mode set the Prophet-10 up with two separate 5-voice polyphonic keyboards. * Single - This mode created a 10-voice polyphonic instrument which could be played on either or both keyboards. * Double - This mode creates a 5-note polyphonic layered sound using both patches. This 4-VCO sound can be played on either or both keyboards. * Alternate - This mode alternates between the two patches chosen. One note would be the first patch and the next note played, on either keyboard, will be the second patch. On the back of the Prophet-10 are two sets of outputs, three XLR (balanced) outputs and a three 1/4' jack outputs. The three outputs correspond to Left, Right, and Mono. Also on the back are two CV (Control Voltage) pedal inputs, and a little matrix of four jack sockets for CV and gate outputs (with last note priority), CV and trigger in (for voice 5 on the upper keyboard), and switch sockets for release, program increments, and sequencer control. The Sequencer on the Prophet-10 was originally optional. It could be installed in the factory before the unit was shipped or it could be retro-fitted at a later date. The sequencer recorded up to 10,200 events the contents of which could be stored onto a Braemer micro-cassette drive located on the side of the instrument. It’s a fiddly process but it was a big step up from the previous Exatron wafer drives which could only store 2500 events and had a brilliant trick of destroying themselves when they jammed. It does appear that some used Braemer tapes may be available here: https://sequentialcircuits.com/prophet10parts.html"

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