Page 1 of 1

SOS! SP-555 audio stops working after 5 minutes-Overheating?

Posted: Fri Sep 13, 2013 1:02 am
by bennybones
Hi everyone,

So I traded in my Yamaha RM1x for an SP-555. I'm anxious to play with my new toy, but alas, it seems I might have gotten screwed.

Cosmetically, the unit is fine. It powers on, LEDs blink, and all pads are responsive. However, after I play with it for 5-10 minutes, the audio drops out. Almost completely. The unit is still playing, because I can *faintly* hear audio through both my headphones and the ouputs, but all but disappears. No distortion though.

I've tried different power adaptors to make sure it wasn't a current problem. I've wiggled and pushed the volume knob every which way, so I know it's not a bad pot connection.

When I turn the unit off and on again, the problem lingers. I usually leave it turned off for 5-10 minutes, and then it's normal again.

I'm assuming some component is overheating or something, since it works for a while and then stops. My guess is that it starts working again once it's had time to cool off. Have any of you encountered this before? I've done some DIY, but I'm no good at troubleshooting - if I can isolate the component, I can swap it out no problem.

I'm a poor student, so I want to avoid sending it in if possible...

Re: SOS! SP-555 audio stops working after 5 minutes-Overheat

Posted: Fri Sep 13, 2013 1:48 am
by Om_Audio
I opened mine up just now- did not remove down to front pcb yet but as I expected there are no heatsinks. More likely a bad capacitor or some other issue. I will check on the DIY guitar pedal forums I am on to see if there are any obvious plsces to look for issue like you describe.
C

Re: SOS! SP-555 audio stops working after 5 minutes-Overheat

Posted: Fri Sep 13, 2013 2:12 am
by bennybones
Thank Om!

I appreciate it! Is the Service Manual available anywhere? I found some for my older Roland gear, but the 555 is nowhere to be found...

Re: SOS! SP-555 audio stops working after 5 minutes-Overheat

Posted: Fri Sep 13, 2013 2:16 am
by Om_Audio
No the 555 is still in production I think. At least I have not seen a service manual for it. Join some DIY forums and post some questions- someone might say "oh ya things do that when you plug wrong power supply in and damage the pulldown resistor, etc blah blah..." tech talk that might be useful.
:)
C

Re: SOS! SP-555 audio stops working after 5 minutes-Overheat

Posted: Fri Sep 13, 2013 2:17 am
by Om_Audio
Also EE departments in schools sometimes look for things like this to teach students how to troubleshoot and repair. Maybe there is a school in your area.
C

Re: SOS! SP-555 audio stops working after 5 minutes-Overheat

Posted: Fri Sep 13, 2013 12:36 pm
by Om_Audio
Tear down and did headphone jack mod while I had it open.

viewtopic.php?f=13&t=16967

Re: SOS! SP-555 audio stops working after 5 minutes-Overheat

Posted: Fri Sep 13, 2013 9:21 pm
by bennybones
Trying my luck in the Muffwiggler DIY thread. I'll update here if I get anywhere...

Re: SOS! SP-555 audio stops working after 5 minutes-Overheat

Posted: Fri Sep 13, 2013 9:31 pm
by Om_Audio
bennybones wrote:Trying my luck in the Muffwiggler DIY thread. I'll update here if I get anywhere...


Prob better to start your own thread man. What forum did you choose? Good luck!
C

Re: SOS! SP-555 audio stops working after 5 minutes-Overheat

Posted: Mon Sep 30, 2013 7:22 am
by j0n4th4n
hey,

it might be the a broken cf card, try to use a compatible cf card, i experienced it before

good luck!