Roland S-550

The Roland S-550 is the full-featured member of Roland’s 12-bit S-series sampler family. Released in 1987 alongside its compact sibling the S-330, the S-550 occupies 2U of rack space and expands on the S-330’s capabilities with more sample memory, a dedicated RGB monitor output, and additional I/O.

Specifications

SpecValue
Year1987
Format2U rack-mount
Resolution12-bit linear
Sample Rates15 kHz / 30 kHz
Polyphony16 voices
Multitimbral8 parts
Max Sample Time28.8 seconds (at 15 kHz), expandable
Memory512 KB, expandable to 2 MB
FilterResonant low-pass, 4-stage envelope (4 levels, 4 rates)
LFOSine and peak-hold waveforms
Outputs8 individual + stereo mix
DisplayDedicated RGB monitor output (640x200) + composite
Storage3.5” 2DD floppy disk
ControlMU-1 mouse, RC-100 remote, or MSX-compatible mouse

History and Design

The S-550 represented Roland’s professional-tier offering in the S-series lineup. While the S-330 targeted budget-conscious musicians with a stripped-down 1U package, the S-550 provided the full experience: expanded memory, a high-quality RGB video output for a dedicated monitor, and room for memory expansion.

The two samplers share the same core architecture — the same sampling engine, the same filter design, the same 12-bit converters, and the same disk format. Sound libraries created for one can be loaded into the other (within memory constraints). The primary differences are physical:

  • Memory: The S-550 ships with 512 KB and supports expansion up to 2 MB. The S-330 has a fixed, smaller memory allocation.
  • Video output: The S-550 includes a dedicated 8-pin DIN RGB output producing a color display at 640x200 resolution. The S-330 only has composite video (monochrome).
  • Form factor: 2U vs. 1U rack space.
  • Additional I/O: The S-550 includes more rear-panel connectivity options.

The S-550 Interface

Like all S-series devices, the S-550 was designed for mouse-driven graphical editing. Its RGB monitor output displays colorful menus, waveform editors, and envelope curves. Navigation uses the same MU-1 mouse or RC-100 remote controller as the S-330.

The S-550’s color display is a notable advantage over the S-330’s monochrome composite output. Parameter groups, selected items, and waveform data are color-coded, making complex editing sessions easier to follow.

Relationship to Other S-Series Devices

The S-550 sits at the center of the S-series ecosystem:

  • Roland S-330 — the compact, affordable version of the same engine
  • Roland S-770 — the next-generation 16-bit flagship that succeeded the S-series 12-bit line
  • Roland W-30 — a sampling workstation that pairs the S-330/S-550 engine with a keyboard and sequencer

The S-550 and S-330 are functionally interchangeable for most sampling tasks. Users who need more memory or a color display choose the S-550; those prioritizing rack space and budget choose the S-330.

See Also