Ensoniq Asr-10 power supply replacement.

So I didn’t pull up anything on the search of the forums, but I haven’t used my asr in months now and just went through everything.

At first my scsi2hd wasn’t loading right, amongst the many cold starts I had to deal with. Then after it warmed up it still wouldn’t load my scsi2hd but loaded off of disk. It worked normal for awhile but then I hooked up the output expander and after that got no sound.

Now going into many more cold starts I got it up and running again but no sound and the inputs are indicating they are peaked out with nothing running into them.

Scsi2 had isn’t working right, and no sound after like 10 cold starts. I knew I needed another power supply but have been putting it off. I think the output expander might have killed my analog board too.

I’m ordering a new power supply and I hope it just finally shit out and won’t let anything run, my scsi and now output. Worst case I am thinking I need a new power supply and analog board.

Just documenting this for others who may have these issues in the future.

When the new power supply comes I’ll try to take pictures so people know what they are getting into. If that doesn’t solve everything I’ll post up some pics of changing out the analog board.

The 1/2 hour I was messing with it before it stopped putting out audio made me fall I. Love with this thing again.

Sad there is no modern alternative to this system. Hands down the best synth I have ever touched.

Where did you order the "new" power supply from? As far as I have seen online, all the "new" ones online are basically refurbished. So they end up swapping out the caps and an equivalent mosfet, putting some new thermal compound on it and calling it a day.

Is your SCSI2SD installed internally? If so - Have you at all tried running it external to see if you are experiencing the same issues?

Yea, I ordered a refurbished one where I have to send my old one. I am comfortable changing out parts but not so much soldering. I just want it to be an easy swap out.

No, scsi2sd is a external 3D printed little box powered by usb. It’s always been solid and until yesterday I never had problems with it. When the asr was working right last night I tried to get into it and it would come up with errors or say scsi is disconnected. Not sure if the power supply issue can cause that to fail too.

Not sure what is going with it seems like everything failed on it yesterday.

if the meters are constantly red showing that it is peaked then it may also be short or a blown analog board.

If you run into a dead end and can't repair it, I'll buy it from you and try to bring it back to life. I have an asr-10 disassembled now. Working on the keybed to fix a calibration problem.

The guy redoing power supplies out of Virginia seems to know what he's doing, and suggested to me that refurbing the power supply may reduce the heat output.

If you are going to recap your ASR-10 power supply I read in the FB user group you should buy:

6 of these: 4700 uF 25v https://www.mouser.com/ProductDetail/pa ... Y4Z-LuCcG0

and 2 of these: 3300uF 35V https://www.mouser.com/ProductDetail/pa ... ZjRB0siPcs

I haven't looked at my psu to verify.

Yea, I don’t trust myself to recap stuff. Maybe I should get some DIY pedal stuff to learn on first before I go messing up the n
Boards more.

So got word from the dude I shipped my power supply, analog board, and analog jack board to. He stated I definitely needed a new power supply, some how my expander part of my jack board was “grounded” and I blew a op amp on the analog board. I knew more was wrong with it than just the power supply.

Dude seems pretty straight up and only charging me 40 for the refurb power supply, and 45 for other two boards refurbished. He said that I more than likely had a power surge to cause that damage. I am sure the compromised power supply didn’t make things better. I tested it again before I send the boards off and it was in the worst shape I seen it in. Really hope that I didn’t fry anything else.

Not sure if we has sending back right away today but I have a bunch of pics I can post once I get it all figured out. More than likely when I get back from vacation next week.

Well got the parts in.... got everything hooked up and blew a fuse. Went back and forth with the guy who refurbed my boards and it seems that there is some funny stuff going on with my molex connections being reversed from the pics he sent me. Meaning someone was really Gerry rigging and messing with my board. I am not sure what to think it worked fine until the other night when it just shit out. I had it a few years and besides it taking awhile to start up it worked fine. Although according to him the way they are were connected is wrong and it should have been blowing fuses...


The red wire should have gone to pin 1, but on mine the red wire connected to the bottom pin. It’s like they had something flipped around and went with a molex connector that was opposite to the way it should be.

LOL don’t ask me....

I would post my pictures but they are “wrong” and I don’t want to confuse anyone.

So moral of story. Some of this vintage stuff is really slapped together for someone to make a quick buck. Seen a sp-1200 with the fuse bypassed, amongst some of the vintage gear I ran across.

I’ll try to find a way to boil this down into something more presentable for my case. I’m just going to send this thing off I think. Too much goofy stuff going on for my limited experience with this stuff.