Inputs
Outputs
The Pro-1 is a clone of the popular retro classic Sequential Circuits Pro-One which was once conceived to be a monophonic Prophet-5. Those familiar with recordings by Depeche Mode and Yazoo will enjoy a recognition moment or two with the Pro-1.
The two assertive oscillators, each based on a CEM3340 chip, each have sawtooth and square waveforms, an octave switch, fine tuning and pulse width controls. Oscillator A can be synchronized to oscillator B, the second tone generator is additionally equipped with the triangle waveform and can be switched to low mode as well as disconnected from the pitch control. Both VCOs are combined in the mixer, here you also find the noise generator, which can be replaced by an external signal. The nice basic sound is processed with a characterful 24dB lowpass filter, which is also known as Curtis VCF. It behaves similar to a Moog filter, but sounds different from the transistor cascade due to the IC CEM3320 used. The two crunchy ADSR envelopes are permanently assigned to filter and VCA. An LFO with three waveforms is connected to the destinations via the modulation bus. Among the special features of this instrument are the waveforms that can be activated simultaneously in both oscillators and the LFO.
The modulations are assigned on the left of the control panel. The filter envelope, oscillator B and the LFO are available as parallel sources, each with its own attenuator. Via switches these are assigned to the destinations frequency oscillator A+B, pulse width oscillator A+B as well as cutoff directly or via the modulation wheel (or midi controller). Used carefully, wild oscillator drifts, sync sounds, sirens, FM for filter and/or oscillator A as well as pulse width modulation are possible. Turn it all up at once and it gets really wild! The modulation bus is the hottest feature besides the sound of the Pro-1.
The ingeniously simple sequencer grants access to two patterns, each of which can be up to 40 steps long; pauses can also be programmed. The notes for this are played in via a connected MIDI keyboard. After input, the patterns can be transposed with the keyboard. The arpeggiator primarily offers the playback modes Up and Up&Down, but can also be integrated into the pattern. The synchronization to other equipment is done via the analog clock input or MIDI/USB.
I was very pleased with this synth. It's sound is very, very close to the original, construction is better than expected for the price and it is fantastic value. I did find the quick guide a bit wanting and there doesn't seem to be a proper manual online. It's pretty straightforward to use if you have experience but a novice would need better explanations of some of the controls. Overall though, highly recommended.
Having used the original back in the 80s, it’s slightly smaller control wise. But the look and feel is the same. Sounds exactly like the original. This was the best price I’ve seen. Delivery was fast. Happy with this purchase.
I have only just received the Pro-1 but already I can see its potential with respect to sound design. I'm not sure how it compares to the original but this unit sure sounds good. I can highly recommend this synth.