He uses 5 D-550 racks on Michael Jackson's "Dangerous" album. Here's a picture of him on Timbaland's Masterclass at 1:26.

As if this isn't enough, Jones' collection of sound sources is breathtaking. Inhale deeply for an (incomplete) overview: Fairlight Series III; Yamaha TX816 rack; Akai S1000; Roland Super JX, MKS50, D50, Jupiter 8, Juno 60, D550, and MKS20 digital piano; Korg Wavestation; Prophet T8; MiniMoog; Vocoder VP330; Yamaha KX88 and TG77; and somewhere in a corner his old 808 drum machine. Still there?

"I bought the new D550 rack unit because it does have great potential for new sounds in the future, although, funnily enough, a lot of the current sounds remind me of my Series II."

This article states that Jerry's studio includes "Clavia Nord Electro 2, Clavia Nord Lead, E-mu ESI-32, E-mu Proteus 1, E-mu XP, Korg Wavestation, Roland D-550, Sequential Circuits Prophet T8, Voce V3, Waldorf Microwave, Yamaha DX7, and Yamaha TX-816."

List of equipment used on the album Universal:

SYNTHS • Emu Proteus 1 (x2) • Emu Proteus 2 (x2) • Emu Proteus World • Emu Classic Keys • Korg M1R • Korg O3R/W • Oberheim Matrix 6R • Oberheim Matrix 1000 • Quasimidi Quasar • Roland Alpha Juno 2 • Roland D550 • Roland JD800 • Roland JV1080 (with Orchestral, Vintage Synth, Piano, and World expansion boards) • Roland JX8P • Roland MKS30 • Yamaha DX7S • Yamaha TX81Z (x2)

SAMPLERS • Akai S1100 • Akai S1100EX

RECORDING • Alesis Quadraverb • Digitech Vocalist (hired) • Fairchild compressors • Focusrite EQ • Opcode Studio 4 MIDI interface • Pultec EQP1A EQ • Urei 1176 compressors

COMPUTERS & SOFTWARE • Apple Macintosh Quadra 650 • Digidesign Pro Tools II & 442 interface • Digidesign Sound Tools II • Emagic Logic Audio v2.5.3

As cited in the gear list of this May '92 feature in Music Tech magazine

"I used a Korg T3 which belonged to Dead Or Alive, and that has a lot of good string sounds. Cubase was the main software package, although it wasn't used throughout, as there's not even timecode on some tracks. The Yamaha grand piano was there, and a Korg M1. I had a Fishman pickup on the viola, which is a fantastic English design, and a Barcus-Berry violin. I used my old Oberheim polysynth, and an Akai S900 sampler with a lot of 8-bit violin samples done for the first solo album, which were still perfectly good thank you very much! Then there's a D550 module, an Oberheim Matrix 1000, a lot of drum samples on an Akai S1000, some from an Alesis drum machine, some Prophet VS, a few bits from a Yamaha TX816 rack, and an OSCar solo on 'Ukraine'. I still use the Yamaha KX88 as the master keyboard because I like the touch, but it could do with more splits and it's not very easy to program. But there's less equipment here than on my first solo album — I hadn't really rushed out to buy any new equipment."

In a Sound On Sound article, Tom Lord-Alge is listed as using the Roland D-550 synthesizer in his gear collection.

"Ciani is no newcomer to synthesis, or to Roland instruments. “I have used Roland gear for about 25 years now,” she says, “going back to the MC-4 and the MC-8 used on my first recording, Seven Waves. In fact, I love ‘vintage’ synths. and used the Roland D-550 extensively on Silver Ship as well.”"

Aztec Camera's Slow Build from Musician, November 1990 by Scott Isler

At home he has a Yamaha DX7 and Akai S-900; on this tour he has access to a D-550 module and Korg piano, all of which he plays badly. He's also been singing ideas into a Sony microcassette recorder.

Jerome Froese lists the Roland D-550 synthesizer as part of his gear collection on his official website, Jerome Froese / Moonpop - Gear Studio.

In an article by KeyboardMag, David Sancious mentions using a Roland D-550 in his 19-inch rack setup.