Twin oscillator mono synth with arpeggiator and sequencer
The Prophet 5 has established itself as today's most popular programmable polyphonic synth. The American designers have used the same expertise and in many cases the same layouts and components to make a mono synth at a budget price. Vince Clarke explains why the Pro One makes him a happy man:
"For a start it's very light and the layout is easy to understand. There are two oscillators and the whole thing is really simply made. The front panel is moulded plastic and there are two wooden panels at the end.
I took mine apart once and every screw does two or three jobs — the one for the side panel holds a circuit board as well. It's a clever design; they've got the maximum out of it to keep the price down.
"Oscillator A has got sawtooth and square waves, oscillator B has sawtooth, square and triangular waves, and it acts as another form of modulation. The keyboard is three octave C-to-C, a sensible note to start on. The noise source is really strong and the volume for that also controls the audio in.
"You can feed an external signal into the back of the synth and use it to trigger the Pro One — it's not true synthesis, you can't alter the pitch, but it can make some strange effects.
"There's a sync switch to lock the two oscillators together and portamento with an automode switch, that's quite handy. You only get portamento when you hold down two notes at once so you can bring it in just when you need it.
"The modulation can do a lot, but it's complicated. You wouldn't want to play around with it too much on stage. Its sources are the filter envelope, oscillator B and an LFO, and they can be sent individually or all together, either direct to the rest of the synth or via the modulation wheel.
"You can affect the frequency or pulse width of both oscillators and the sweep of the filter. All the modulation controls are in their own section down the left-hand side of the front panel.
"On the oscillators, the best things are the square and triangular waves. The triangular is really pure and hollow. It's not very loud, so you have to back it up with the square wave which has a lovely flutey, pipey sound that I really like. They already sound big without any pulse width modulation. You don't have to detune them to get a thick sound, it's there from the start.
"All the controls have a lot of variety and the filter has a wide range on it. Sometimes I use the filter alone for a bass drum sound adjusting the attack to give you the right amount of click. It's not a brilliant bass drum, but it's better than on a lot of rhythm boxes. It's a 'fast' sounding synthesiser, all the sounds get going very quickly, they've got a lot of attack to them.
"I like the arpeggiator because it just plays the notes you're holding down. It won't run up and down a chord putting in an automatic scale, but it can bounce between two bass notes and I find that more useful.
"Also there's a latching switch so you can take your fingers off the keys and it carries on playing the arpeggio you've fed in.
"You have to be careful if you want to change it while it's operating, because if an extra note slips through it will throw you out of time with what else is going on. It can run up the notes you're holding, or up and down.
"As well as the arpeggiator there's a sequencer, but it's limited. It can only take up to 40 notes in two lots of 20 and it's difficult to program. All the notes are the same length, like clockwork, and if you want to put in a space you have to turn the record button off and count.
"The other funny thing is, I've found when I trigger a sequence in the Pro One from my Roland MC4 it never plays the first note. You have to start the MC4 from the last note of the previous sequence... I don't know why."
"Well, the inherent sound is really strong, really big. The modulation section can do a lot, but I can't always understand why it's doing it. The keyboard is light and springy, you couldn't thump it too hard.
"When I first got mine the fuse went; I've heard a lot of people say they had the same problems.
"The case is flimsy, so you'd have to get a flight case if you were going to carry it around a lot. I don't think I'd use it on stage — I panic too much — but if you had one or two sounds set up, maybe used by a guitarist who was doubling on synth, it would be great.
"In the studio I've used it for nearly everything. I've very rarely found a sound it can't get."
Review by Vince Clarke
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