This Sound On Sound article states that Emerson owned an Oberheim DPX-1.

List of equipment used by Klaus Schulze, from the February 1993 issue of Sound on Sound:

4x Akai S1000PB (32MB) 2x Akai S1000KB (32MB) Akai S900 Akai S612 Akai S7000 Moog Modular CIII 2x Moog MiniMoog Studio Electronics MIDIMini Mellotron Yamaha CS80 Yamaha CP70 Yamaha TX81Z Yamaha SY99 Korg M1 Korg M1 EX Korg T1 Korg T3 Korg DVP1 Roland U110 Roland U220 Roland D50 Roland S50 sampler & monitor Roland Planet S & editor Roland Super Jupiter & editor 2 Roland TR505 Roland Octopad Roland JD800 Roland Super JX10 4x Hohner HS2/E sampler 5x Hohner HS1/E sampler Hohner HS1KB sampler Waldorf Microwave GDS computer synth Misc. Crumar keyboards Fairlight CMI Series II SCI Prophet 2000 SCI Prophet 2002 Emu Proteus/2 Emu Proteus/3 World Emu Emulator II Kurzweil K1000 Kawai K4 EMS Synthi A PPG Wave 2.2 Linn 9000 4x Oberheim DPX1 Yamaha RY30 drum machine Sonor timpanies and octo toms Paiste gongs and cymbals Martin 12-string guitar

"I'm using a rack system, composed of two Oberheim DPX-1 sample players, which play Mirage, Prophet, and Emulator disks. I've also got a rack-mounted DX7, a Roland digital piano module, a Roland Super Jupiter module, and a Roland DP-5 multi-effects unit. It's all controlled by a Simmons computer mixer, which has about 64 programs in it. Through that mixer I change all the MIDI channels on all the modules. I control the mixer through a Roland MIDI MKB-200 keyboard controller. You can assign split points to the keyboard, so I do that for a lot of songs where there is, say, a piano, a koto, then a trumpet sound. Rather than take an Emulator and things like that on the road, I wanted a very easy live setup, so that I could do most of the work beforehand. That's another reason for having those two Oberheim sample players. An Emulator disk takes a long time to load, and you can't say, "Sorry, Madison Square Garden, I've gotta load this disk." We've worked out a system where we can keep switching back and forth [between the DPX-1s]. The only other alternative would be to use something like a hard disk, which I don't really want to do because the hard disk has to be installed in the Emulator and is notoriously unreliable on the road. The good thing about having a rack system is that it can be well protected. You can throw it off the back of the truck and nothing will happen to it."

Taken from an article authored by Richard Karsmakers in October of 1995.

Karl: What musical hardware do you use?

Jens: Oberheim Matrix12, matrix1000's, Matrix 6R, DPX-1. Korg PolySix (I have around 10 of those), Yamaha DX7+TX816 rack, Roland D20, DS-330, Hammond + Leslie (I have two actually), Korg CX3 as a "touring hammond", and a bunch of others. I also rent stuff a lot.

I'm not too crazy about the "new breed" of keyboards like the K2000 etc; they sound a bit thin to me. But whatever.

"I've been using Oberheim for donkey's years; but for this tour I wanted to go beyond what I had last time, so I got in touch with them and found they were developing the DPX. That was exactly the way that I was going, except that every time you want to change a sound, you had to put in another disk. In the beginning, I decided to get nine of them and put all the sounds in and allocate every preset to a different sound. About halfway through that process, Oberheim asked me what I wanted and I said, 'make me a hard disk version of the DPX1'. So they said 'OK' and built it. Now I have everything on two hard disk systems. I guess I could have had two Emulators, but having two little units in a rack is much better."

spotted in the video

Included in his studio are synthesizers such as the Roland MKS-70, two MKS-50s, a MKS-80 and D-50; Yamaha TX-81Z; four Oberheim Matrix 1000s, E-mu Orbit and Morpheus, and a Casio VZ-10M. Sample players include Kurzweil 1000AX+, Roland U-110, Oberheim DPX-1, E-mu Proformance Piano and Proteus (as well as the Proteus 2 and 3), Alesis NanoBass and samplers, including a Casio FZ-10M, two Akai S-1000s and three Akai CD-3000s. He also turns to E-mu Procussion, Roland R-8M, Alesis DM-5, Roland BD-1 and a Roland SPD-11 for drum sounds.

David Ferguson's equipment list:

Apple G3 266 computer, 96Mb RAM/4Gb HD. Akai S3000XL sampler. Alesis ADAT XT digital recorder/BRC remote. Alesis Microverb effects. Bit 99 synth. Drawmer DS201 Gate & LX20 compressor. Emagic Logic Platinum 2.6 sequencer. Emu Proteus 1, 2 & 3 sound modules. ("On the album, the 'Hall Strings' preset from Emu's first Proteus module is used a lot, because it's a great marcato string sound.") Emu Proformance piano module. Ensoniq VFX synth. FriendChip Timecode Refresher. Iomega Jaz drive. Korg 1212 PCI card. Korg DRV3000 effects. ("Weird and sometimes wonderful.") Korg Wavestation SR synth. Lexicon MPX1000 effects. Logan String Melody keyboard. ("The last of Random Hold.") Mackie 32:8:2 mixer. Oberheim DPX1 sample player. Roland D550 synth. Roland S760 samplers/SP700 playback unit. Sony 600Mb optical drive. Sony DTC690 DAT recorder. Spirit Absolute 2 monitors. SPL Vitalizer enhancer. Symetrix 511A noise reduction. Tascam DA30 MkII DAT recorder. TC M2000 Wizard effects. Yamaha AN1x synth. Yamaha SPX50 effects.

David Bergeaud confirmed his use of the Oberheim DPX-1 by listing it among his synthesizers on eBay, indicating its role in his various game projects. For further information, refer to the Facebook group post on Ratchet & Clank fans.

https://www.facebook.com/groups/ratchetclankfans/posts/8289617861060344/