Someone might have already tried to recap the unit. The two caps are definitely wrong polarized. Better check if there are more of them put inside the wrong way
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Looking for Ensoniq DP Pro Service Manual / Schematics
- Thread starter 58Glammer
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beyond the gallbladder!
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I purchased it new about 25 years ago, never had an issue, aside from the battery.Someone might have already tried to recap the unit. The two caps are definitely wrong polarized. Better check if there are more of them put inside the wrong way
In the end, the way your caps sitting on the board is right and they had a missprint on the board
.. I got to check my units again. The battery btw always seems to be an issue in this model. I also realized lately when I put batteryholders into all of my 3 units, that in one of them, even if I put in a new battery the low battery message still comes up.
Would be great to have the schematics to look that up..A friend of mine has a DP Pro as well. I will take a look into his unit.
Maybe it‘s printed wrong on the board and the position in your unit is right.
I‘ll check and report soon.
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I got the DP Pro from a friend to recap the unit.
I had a check on the elcos I thought are wrong polarized in your unit.
And guess what.. the same in his unit.
So it really seems like it‘s written wrong on the PCB...
I barely remember it was the same in my units and I thought it‘s wrong.
I mean, my units all work.
But I think, I will revisit my other units.
This time I went all „hole through elcos“ .. This is the unit I was writing about before. It still worked, but had the typical battery low message. I left the new caps in the same polarisation like they were before. Including the two that are marked the wrong way. They are close to the section, where you adjust the digital distortion level of the left and right channel. Them work both way.. On the other units I installed them like marked on the board.
Anyways. With the through hole caps the unit sounds great
I used larger voltage values. E.g. instead of 10/16v I used 10/35v.. All Panasonic FC
Anyways. With the through hole caps the unit sounds great
I used larger voltage values. E.g. instead of 10/16v I used 10/35v.. All Panasonic FC
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I'm also looking for the schematics/ service manual for the Ensoniq DP Pro. The only issue I'm having is that the left input is attenuated when compared to the right input, by about -20db. I'm going to try to reflow the area that I assume is the input opamp & associated bits, but I really would like to check out the schematics!
I really recommend to recap the unit.. these smd caps were bad. Meanwhile I recommend to use the "pressure and twist" method to get the old SMD caps off. But you should watch some tutorial videos and practice on a scrap board to get into it.
Best method IMO. ..
With my work on several DP4+ units, leaked caps had often an effect on the opamps ..
But also check underneath the in and output XLR s if there are solderblobs.. I had solderblobs on 2 units in that area...
What happens if
Just looked for the technical documents again and could not find it.
What happens when you use the +4 / -10 db switch on the backside of the unit?
Just looked for the technical documents again and could not find it.
Obsoletemachines
Member
I got another DP/Pro after a long time. No sign of cap leakage visual and probing reveals no noise increase. It all depends how its been racked and whether its been in use at all. This was a house comp in a church. It's my third DP/Pro but this one I'll keep.
+4/-10 is whether your mixer sends are set to pro level +4 or -10. in most cases -10db.
DP/Pro doesn't suffer from same cap leakage as the DP/pro - there is a good deal less heat. Switch Mode power supply instead of linear power. Sorry but thats errant info. Inside DP4+ even with passive cooling can hit 75C near caps. The DP/Pro will not get anywhere that hot.
No service manual, this is the point where Ensoniq got merged into E-mu and they quickly realised a 60pc return rate, faulty, on products wasn't a way to a run a business. E-mu shut Ensoniq down pretty quickly and the last products ASR-X pro, Fizmo and DP/pro came out - all sporting the thin wafer VLSI ESP2 chip. Note the algorithms are not the same as the DP4, DP4+ or ASR-10 but still very good and they had top engineers/producers make the presets like Chuck Zwicky.
You don't need a service manual.
For the attenuated input look at the 'input pot' - it's a mechanical consideration and there will be more resistance on one side. Take the input pot out altogether to isolate the issue.
+4/-10 is whether your mixer sends are set to pro level +4 or -10. in most cases -10db.
DP/Pro doesn't suffer from same cap leakage as the DP/pro - there is a good deal less heat. Switch Mode power supply instead of linear power. Sorry but thats errant info. Inside DP4+ even with passive cooling can hit 75C near caps. The DP/Pro will not get anywhere that hot.
No service manual, this is the point where Ensoniq got merged into E-mu and they quickly realised a 60pc return rate, faulty, on products wasn't a way to a run a business. E-mu shut Ensoniq down pretty quickly and the last products ASR-X pro, Fizmo and DP/pro came out - all sporting the thin wafer VLSI ESP2 chip. Note the algorithms are not the same as the DP4, DP4+ or ASR-10 but still very good and they had top engineers/producers make the presets like Chuck Zwicky.
You don't need a service manual.
For the attenuated input look at the 'input pot' - it's a mechanical consideration and there will be more resistance on one side. Take the input pot out altogether to isolate the issue.
