Roland S-50 / S-550

Roland S-50 Image

Roland S-50

Among Roland's line of early keyboard samplers—the S-series—the S-50 can be thought of as the professional model. Still, by today's standards it would be considered limited and lo-fi. However for its time it was a powerful instrument which can still prove useful for many music applications today. It offered a full 61 note keyboard with velocity and aftertouch sensitivity and 16 voice polyphony which was great for live and studio performances. It's easy to use, has an external CRT monitor support for large graphic editing and disk-loadable samples and operating systems (version 2.0 or later is best).

Though editing is a breeze, it is quite sophisticated and can be much easier when using an external CRT monitor and the DT-100 Digitizer Tablet. You get to draw waveforms, auto-loop, tune, edit the multi-stage envelopes, edit digital filters and quickly adjust loops and samples. There is also a SYS-503 sequencer package software which offers basic drum machine type sequencing. Of course most edit parameters, excluding the sequencer, can be modified and tweaked via the Alpha-Juno type alpha-dial.

It's too bad that such a nice looking and well designed synthesizer is home to a tiny 512k-WORD sample memory (756k-byte sample memory). And with 15 to 30kHz variable sampling rates at a 12-bit resolution, the sound quality is almost nice. Roland has a vast sample library of sounds ready to be loaded via the built in 3.5 inch disk drive. Samples of your own (up to 28.8 seconds at 15kHz) can also be saved to disk. The S-50 version 1.0 allowed for 16 samples or "tones". Version 2.0 expanded to 32 samples or "tones". Sampling modes include manual, auto and previous.

Roland S-550 Image

Roland S-550

A rack-mounted version of the S-50 came in the form of the S-550, which also had double the sample memory (1.5 Mb) and more importantly, real-time filters (called time-variant filters) derived from LAS-type synthesizers like the D-50. A slimmed down, consumer friendly version of the S-550 was also available as the S-330. The S-50 supports the DT-100 Digitizer Tablet and an external CRT monitor, but if you would like to connect the DT-100 to the S-550 (or a S-330) you will need a RC-100 first. The S-50/S-550 has been used by Vangelis, Duran Duran and Jimi Tenor.

Lookup Roland S-50 / S-550 Prices

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Are you looking to buy or sell a Roland S-50 / S-550? Post an ad in Gear For Sale or a request in Gear Wanted. For spare parts and repair services check out Gear Services & Other Goods. Our forums also has a Buyer’s Guide section where you can ask for advice on buying synthesizers.

35 Visitor comments
jim atwood
January 19, 2012 @ 9:02 pm
@louis Thanks for the great info. In my case it was not the relay rather it was the CPU board that needed replacing. The IC14 chip was bad. My original Jack board which houses the relay is still intact. I recently fixed my Casio CZ5000 with a similar problem and that turned out to be the relay so indeed the relays can cause problems. The CPU board was ultimately the problem with the voices dropping out and the static distortion. Thanks again for the info.
January 18, 2012 @ 7:08 am
@ted/jim; output distortion on the S50 can be caused by dirty contacts of the relay that switches the outputs on power up. Due to the outputs being hard wired to voices, it will then only appear on certain voice groups. In my S50 the first 8 voices where fine but the second 8 sounded distorted. If your relay is slightly better it can also be the upper 4 or 2 voices that are affected.
This was fixed by cleaning the relay and resoldering its contacts to the board.
January 11, 2012 @ 12:11 pm
If anyone needs S50 - S330 or S550 disk library here can find them, included the utilisy Sdisk necessary to build the diskettes. Not sure if Sdisk would work on WinXP or needs earlier operatinf systems but you can try.

Have fun! Carlo
December 16, 2011 @ 4:30 am
I have an s50 roland. bought it as used from Japan. when i on , it says to insert system disk. i tried in the net to down load. But i can't get. Please help me to get the system file to operate the s 50. no function keys working, exept the message " insert system disk "
Jim Atwood
November 29, 2011 @ 11:32 pm
@ted - I have an update on my Roland S-50 distorted output problem. I've been able to isolate the problem to distortion happening on the 15th and 16th notes being played. The S-50 has polyphony of 16 voices. The first 14 sound fine. The last two distort. I have no idea what generates the voice output or how it's dispersed. Many think this is an output board problem but it could be chip related. I'm posting updates on my blog as I discover new info. Hopefully one day we'll find the problem that seems to be increasing with the S-50.
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  • Check Price
  • The link above will take you to an eBay search for this synth to see active listings. If you don't find it there, try looking in our forum marketplace or post a wanted classified.
  • Specifications
  • Polyphony - 16 voices
  • Sampler - 12-bit, 30kHz, variable
  • Multitimbral - 4-parts, 4 outputs
  • Memory - 756kb, 28.8 seconds total sample time
  • Filter - Hi-pass, Low-pass digital filters
  • Arpeg/Seq - SYS503 sequencing software
  • Keyboard - 61 keys with velocity and aftertouch
  • Control - MIDI
  • Date Produced - 1986 - 1987
  • Resources & Credits
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