Roland D50 Output problems

Hello fellow synth enthusiasts!

This is my first topic, and I’d like to cut right to the chase. I brought out the old D50, replaced the internal battery, reloaded the factory patches using Bome SendSX, and she started right up - to my dismay, the volume is impossibly low coming out of the R/L and headphone outs. I opened her up trying to find a leaky capacitor or something of the sort, but I can’t find anything.

Has anyone else had this problem? If so, how did you fix it?

Thanks in advance everyone, this is my pride and joy over here.

I am guessing that you are experiencing a faulty op amp in the output circuitry. And I’m guessing the culprit is IC5, which is (unexpectedly) on the bender board - it amplifies the signal going to the outputs and the Headphones.

But first, make sure the Volume slider hasn’t crapped out, by making sure that it attenuates the sound properly as you move it. This is not likely the fault, but it’s quick and easy to check.

I guess that’ where the sound goes to get bent??? :slight_smile: Thanks so much Sam, I’ll be picking up a new IC5.

P.S. big fan of the youtube series!

Hi - thought I’d follow up on this thread as I have just purchased a used D-50 which I love.
Output jack issues that I’d like some guidance because I open it up for surgery: connecting the cable to the Right output, sound come out properly. Once I plug cable on the Left channel, right channel goes totally mute and sound comes out only from Left.
Tried diff cables, mixer and even direct connection to speaker so it should be a D-50 problem.
Appreciate any insight in where to start for fixing. Thanks!

The D50 outputs jacks have a switch built in, so that if just one jack is used, it receives both L and R signals. When plugs are inserted into both jacks, these switches preclude the signals from summing, so that the R output goes only to the R jack, and L to the L jack. If you are losing signal in the right jack with two plugs inserted, then I think the R signal is not there (and with only one jack plugged in, you are always hearing just the L signal, regardless of which output jack you are plugged into).

So try using headphones, and see if you are hearing both sides of the output there. If you do hear both sides, then the problem is isolated to the jack board or the wiring connector to it. That should be an easy fix.

If one side is missing in the headphones, then I would take a look at IC6 on the bender board (a 4570 op amp) and see if you are getting the right output at pin 1. For comparison, the left output will be at pin 7.

1 Like

Line signal is IC6 - phones are line signal amplified by IC5

On Jack Board (right) if only Lower connected then signal summed - if only Upper connected then NOT summed

hope this helps

Hi Sam Very pleased to discover your youtube channel today and then the forum. I have a Roland D50 and with some sounds like famous industrial, after few seconds normal, it is asif noise generator added like withe noise I don’t kown how to call it. Is it a common issue ?

Thanks for this thread. I just bought a D50, same issues with both outputs work, but not together, plug in headphone and only hearing one side. Sooo, IC5 and/or IC6 needs to be replaced (likely). My question is where might one source 5216 and 4570 (or equivalent)? I see that they aren’t listed on the syntaur site. Thanks again for the help!!


Hello all!

So I replaced IC5 with this op-amp but my problem remained - still no output.

I began poking around with my oscilloscope leads to find the point where the signal stops, and as if by magic the signal came back as it should. I’ll update when I fix it completely.

Thanks @Sam

Wiggling the volume fader fixed it for me. I’ll clean it later. I like your youtube channel!

Hello. New here. But with the same problem, only with D550. Having red above, I replaced 4750HA. The problem still remains. Any other ideas what may be the issue?