I tried searching for this and couldn’t find anything, which was a bit of a surprise…
Anyway, I’m thinking of adding a Prophet 5 module to my P5 keyboard, with the idea of creating a monster true stereo Prophet 5. As it is now, I end up double tracking it all the time to get really nice wide pads, which sounds stunning - but it would be a blast to be able to play and tweak both layers at the same time.
In practice, I assume the module would respond to anything I do from the keyboard controls, so they’d always be “in sync” - and then for any subtle variations, I would further tweak the module directly.
Anything I’m missing with this approach? I know it might sound excessive, but the P5 is my favorite analog poly, so why not. Having 2 of them layered, subtly detuned, and panned apart is absolutely glorious - way better than simulating stereo with a chorus pedal or plugin.
Thoughts?
I think my opinion would be influenced by whether or not two P5s can be polychained. I'm not sure if they can or not, but whether they can would be the first question I'd be interested in. If they can, the cost of adding a P5 desktop to existing keyboard begins to look pretty good because it means that for only $1700 or so more than an P5 expansion board you've not only turned the P5 into a P10, but you've achieved your stereo setup wants with the configuration you've described above.
The other side of the coin -- on many of the albums the Prophet 5 is historically famous for, the P5 is multi-tracked (as you mentioned you're already doing). This may seem like "poor man's stereo", but much of the time, this approach was actually responsible for much of why the P5 sounded so good. A common technique was to mono record a part and pan to the left channel, then record the part again, with very slight natural variations in playing (perhaps also slightly different patch settings, and with sequencers maybe quantization differences), and then pan that new recording right. There is a certain dynamic to the result of this technique that is not quite the same as having a single synth output to L and R simultaneously, and of course it's relatively economical to work this way.
But, that's coming from someone who doesn't play live and is looking at things from a studio musician perspective only. Also, my current FX chain for the P10 looks like this: Boss CE-2W > Strymon Mobius > Strymon Timeline > OTO Bam .... which sounds great with the tone of the P10, but would be an expensive setup if that only represented one stereo channel and I needed 2 of each pedal.... I would more likely route both mono signals into the same pedals, which would mostly negate the benefit of having 2 synths going to each channel.
I can also see some arguments in favor of doing it -- having two P5s would give you a unique setup that probably not a lot of people have, there would be a time savings involved in not needing to double track parts, and maybe most of all you know best what sort of setup you want and that's important for inspiration. For me, I'm a big fan of the poly unison mode of the P10, so I'd be happy with an expansion card for a P5 but it's really a very subjective matter.