S‑50 Noise, Static And Distortion Fix


Open Mirror from Australia has installed this new PCB and Relay setup into his S‑50 and reports excellent results

The distortion he was experiencing has disappeared

Here are some Before & After sound comparisons -plus- images of his installation


Before & After Sound Comparisons
(click on the audio format you want to hear)


S-50 Coil              S-50 Coil




S-50 Coil

S-50 Coil

S-50 Coil

S-50 Coil

S-50 Coil

S-50 Coil

S-50 Coil

S-50 Coil

S-50 Coil

S-50 Coil

S-50 Coil


Tom Arnold, another S‑50 owner, has supplied an excellent solution which has been verified by several online visitors here. He designed a very small PCB which is used to replace the single relay coil by using three inexpensive, low current and easy to source relays. The big advantage to this solution is these new relays are easily swapped out when they fail. According to Arnold, the S‑50 design is prone to failure because the original single relay coil and replacement relays will eventually fail over time. Since it's very difficult to remove and clean the factory installed relay coil, swapping out three 0.85 relay coils makes more sense because they are socketed on this new PCB

"This is a 3DPDT relay board to replace the 6PDT relay in the Roland S‑50. Two holes in the middle are for hold‑down screws. I recommend putting in sockets so you can replace the relays more easily as they will go out again the way they are being used."

The best price I've seen for these new relays is only 0.85 each from Allied Electronics. You'll need to buy three 16‑pin IC sockets and three 5V relays (Zettler P/N#: AZ822‑2C‑5DSE)

The bad news is that OSHPark has a minimum purchase of three PCB's. The good news is they only cost $3/each

               S50/S550 DOWNLOAD PCB's designed dy Tom Arnold are available from OSHPark here

               S50/S550 DOWNLOAD 5V Relays From Allied Electronics - here


   S-50 / S-550 ZONE