GForce Sequential Prophet-5 – the Synth and Software Review
A software version of the classic digitally-controlled synth that led to MIDI, with additional 2026 features
The Sequential Prophet-5 was an important instrument the history of synths, but even more importantly it still stands up today – which is why Sequential re-issued a hardware version a couple of years ago. It’s also why several software companies have released models of it.
GForce’s is the latest, and it’s billed as having “teamed up with Sequential for the official Prophet-5 plug-in.” Often that language just dresses up a licensing agreement, but we’ve seen video of Tom Oberheim’s enthusiastic endorsement of GForce’s fabulous Oberheim OB-E and SEM, and this seems like more than that too.
Hopefully no one will be too furious if we’re wrong, but according to our research: upon its release in 1978, the 5-voice Prophet-5 was the first polyphonic digitally-controlled analog synth that could store and recall all its parameters. (The Oberheim 4-voice couldn’t recall all its parameters, and the OB-1 was monophonic.) That made it a lot more practical to perform with than anything that came before it, and the list of famous musicians who used it goes halfway to the moon.
Because it and many subsequent synths were under digital microprocessor control, several manufacturers – that is, five: Sequential, Korg, Yamaha, Kawai, and Roland – got together and agreed on a spec for instruments to talk to one another. In 1983, five years later, MIDI was adopted, and the Prophet-5 was an early step along that path.
GForce walked a line between being pedantically (haha) authentic and creating an instrument that’s current. Their Prophet-5 has a “vintage” knob to dial in the amount of parameter drift, but the instrument also includes two 10-voice layers, several different effects processors, the ability to modulate almost every parameter with its own sophisticated envelope and LFO (called the XMod), voice panning, an arpeggiator, chord memory, of course MIDI control over everything, and MPE.
It also has models of the four different versions of the Prophet-5, with different envelope characters and filter designs as it evolved. And filter Q compensation for resonance to keep the sound level consistent.
Out of the box
GForce included the 40 original programs as well as a library of – we’re taking their word for this – 460 additional ones. A pleasantly surprising percentage of the programs in this instrument is very usable, almost out of the box.
At a minimum, many if not most of the original Sequential programs will want some reverb added (because they’re bone dry). And GForce’s built-in reverb is tuned very well to this instrument – it doesn’t sound plastic, it sticks to the analog synth sounds, and it doesn’t have the unpleasant sparkles we all hate in cheap reverb.
In the other direction, many of the included programs have a lot of reverb and garishly slow amplitude release segments. That sounds big and impressive, but those of us who prefer not to have notes ringing all over the place will want to adjust the programs and save them.
Heads up if you’re first experimenting with the instrument and haven’t read the very clear manual (which is both complete and concise): the reverb defaults to being per patch, but there’s a little lock icon to make it global. Same with all the effects.
Once adjusted, that big and impressive sound becomes really satisfying. The default program when you insert the Prophet-5 is called “It’s a Prophet 5.” Yes it is – a big and impressive, buzzy, rich analog synth sound we all love, complete with aftertouch opening up the filter.
It’s all about me
On a personal note, playing some of the patches and poking around the Prophet-5 brought back pleasant memories of one of my first film scoring gigs, right after college. This was before we all had our own instruments, let alone project studios, and I’d hired a synth player who brought his Prophet-5 to the recording studio and overdubbed written-out parts on their 2″ tape machine.
One of the sounds I described to the synthesist (I had no idea how to program a synth then) had a pssssh component to it. The G-Force Prophet-5 has a white noise generator to create that sound, which was surely what he used.
At first the white noise didn’t blend seamlessly with the sound the way I remember it doing, and it doesn’t have a filter of its own. The reason is that it’s on/off, so it can just sound like added noise rather than a part of the sound.
There are several ways to go about this, but the one I chose was to lower the instrument’s filter cutoff for a bright sound, set a pretty healthy filter envelope amount, then shorten the filter envelope with a low sustain and fast release so the noise is only heard at full throat during the attack.
Computer resources
We ran the Prophet-5 on two different Macs, using the stand-alone program, the AU plug-in inside Logic Pro, and the AAX plug-in inside Pro Tools. The machines are an M1 Mac Studio Max and an M4 Pro MacBook Pro.
Even with a 64-sample buffer (which is very low) this instrument doesn’t make a significant dent on the CPU. And with that small a buffer setting it’s very responsive.
Random comments
There are always far more things to say about a synth than anyone would care to read about in a review, and GForce has a time-limited demo available. But one of the things to understand about the Prophet-5 is that its voice architecture has two oscillators (that can be synced and mixed).
Oscillator 1 has a choice of sawtooth, pulse (with pulse width), and Oscillator 2 adds a triangle wave. What’s interesting is that you can use any or all of these waveforms, and combining them creates a bright sound that’s hard to describe. This is similar to the Oberheim OB-X8.
Another interesting feature is the layer voice modes in the GForce Prophet-5. There’s a choice of Layer A and/or B, or you can split the keyboard. But there’s also an alternating mode between the two layers, so each successive note plays a different sound. And that’s in addition to being able to program round-robins.
We praised the reverb previously, but the strength of the other effects shows how far we’ve come in the past 48 years. The third and fourth effects slots are fixed with stereo delay and reverb, but the other two can hold a chorus, distortion, a phaser, another filter, tremolo, and compression.
They’re all for real, but it’s the distortion that’s most notable. Host-based versions of that effect in particular have a history of sounding… not good. This one is impressive.
Ergo
Even if you already have a plug-in Prophet-5, this one has excellent effects and a big selection of usable programs. Fellow fans of plug-in models of classic synths should like this one a lot, as will fans of softsynths that are simply very satisfying to play.
GForce is pretty good at this.
Price: $119 (currently on sale for $84)
