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I have joined the cult of the Ensoniq DP/4
Old 30th May 2020
  #151
Quote:
Originally Posted by NEXUS-6 View Post
You know what's really sad...

I know exactly what each portion of this circuit board does. I've learned it the hard way. Few years ago, I've recapped my unit's PSU with slightly larger caps and kinda forgot about it. Sverel months later started using it, noticed a constant choking in the reverb feedback path if the reverb was longer than 5 seconds - it was driving me crazy. I tried everything to fix it, then one day i swapped capacitors to original value, and BAM! machine suddenly no longer had any choking in the reverb.

In other words, i was trying to service a fully functional unit for one good month and in this process i have learned how it works. I can now repair pretty much any DP4+, except i won't do that since i don't do repairs.
Old 30th May 2020
  #152
Gear Addict
 
goodweather's Avatar
@ Don Solaris
I'm close to get a revised DP4+ (can also get a DP4 but will first try the + version even if a bit more expensive) and as I don't know anything in audio electronics but that you seem to know well the DP4+, maybe you can advise me on the following aspects of the repair that has been done about one year ago on that machine.
They repaired the pre-amp circuit. I suppose it is for the mic, or?
They repaired the ADC-DAC converter. Can that still be done with original parts? Will such repair change the sound of the DP4+ or not?
They replaced the capacitors of the power supply. I think this can only be very good.
They repaired the circuits for the logic management (don't know what this is and how that could become broken)
They did a stress test and general controls.
It is great that I got the repair invoice with those details from the vendor but still I want to be sure to buy a well revised machine because this isn't peanuts money.
Thx in advance!
Old 30th May 2020
  #153
Gear Maniac
 
Mr. Syc's Avatar
 

I picked up a NM one that had been stored for 20 years with all docs last year for $500. They’re around
Old 30th May 2020
  #154
Quote:
Originally Posted by goodweather View Post
They repaired the ADC-DAC converter.
LOL! Sure they did.

The Phillips TDA-1541A converter chip that DP4+ uses is one of the most sought after converter chips among audiophiles - it can cost as much as the DP4 unit itself. You can not repair it - you can only replace it with genuine unit. A genuine one will set you back as much as 300 notes. And i doubt they gave that much, while the modern "replacement" ones are fake that don't work at all and just end up heating up like crazy.

Something's fishy in their story.

In general, with the + version, you have to replace all SMD capacitors, since many are all leaky by now, and the unit should be fine. You also need to inspect the I/O section PCM traces around those capacitors - because of the mentioned leakage can damage the traces.

If you never did repair, don't understand electronics, stay away from DP-4+ and go DP-4 which is thru hole and easier to fix. Also, the basic DP4 (non + version) does not use those leaky SMD caps and should therefore be way more reliable at the first place. Just let someone replace the PSU electrolytics and you are set to go. The "+" version is worst than a can of worms due to a lot of potential damage that can happen in the I/O section because there are a lot of leaky SMD caps in there.

Reliability:
DP4 > can of worms > DP4+
Old 31st May 2020
  #155
Gear Nut
 

Amen.
Old 31st May 2020
  #156
Gear Addict
 
goodweather's Avatar
They charged 150 EUR for the complete repair mentioned above. The fact they had to "repair" so much made me hesitating.
I will follow your advice as it is indeed easier to repair thru-hole components than SMD ones.
Thx a lot for sharing your experience!
Hopefully I can still get the DP4. Otherwise, it is just a matter of patience
Old 31st May 2020
  #157
Lives for gear
 
teknosmoker's Avatar
 

Quote:
Originally Posted by Don Solaris View Post
You know what's really sad...

I know exactly what each portion of this circuit board does......
Hey Don,

Thanks for sharing! Posted this question in the GS general forum a few days ago, but no responses so far. Perhaps you could point me in the right direction?



Have 2 units:

- a non-working Ensoniq DP/4+ (logic board is fried)
- and a mostly-working, regular (non-plus version) DP/4.

The 1st input on the DP/4 is kinda’ shot, as it creates distortion upon any signal that passes though it (removes high freqs, sounds a bit like sample rate reduction).


Do you know if it is possible to rip the analog input section from my non-functional DP/4+ and use it to replace the bad analog stage of input #1 on my working DP/4? ....or are the units too different from each other? (I miss my DP/4's! )





-T
Old 21st June 2020
  #158
Lives for gear
 
TobyToby's Avatar
 

Quote:
Originally Posted by jrakarl View Post
Nice work Nexus-6. I've noticed the DP4 prices skyrocket over the last 5 or so years. They all seem to go >$1000 now.. Soon they'll be the price they were new!
I picked up a DP4+ for AU$500 about 10 years ago. I can't remember the last time I saw a DP4+ for sale, let alone for under a grand.
I've bought them for about £150 [the last one 8 years ago or so]. From my cost-to-benefit-ratio perspective I would never pay more than £250 today if I have to purchase one. The DP4 doesn't have a single function that would help to make a production sound better than with other devices. The lockdown might have caused a bit of brain damage to the ones who are asking £875 on ebay UK or $999.oo on ebay US
Old 24th June 2020
  #159
Gear Maniac
My friend offered me his Ensoniq DP-4 for $400

Should I buy it? Is that a good price?

I already have some effects processors and I never paid over $100 for any one of these:
Alesis Microverb 4
Alesis Midiverb II
Behringer Virtualizer Pro FX
Digitech RP500
Electrix MoFx
Electrix Warp Factory
Lexicon MPX 500
Lexicon Alex
Peavey Univerb II
Peavey Kosmos V2
Roland SDE-330
T.C. Electronic M-One original
T.C. Electronics M-One XL
TOA 310D Digital Delay
Yamaha SPX990
Yamaha D1030 Digital Delay Line Equalizer
Zoom MS-70 CDR
and about 20 other guitar effects pedals...

I'm thinking the Ensoniq will fill a void/niche but $400 would be 4x what I paid for any of these other units.

I kind of agree with TobyToby above. The DP4 seems like it should sell $250-$300 on the market compared to what else you can get. The prices I see online for some of them is insane. People are paying $500+ So I suppose $400 is a good price but I'm wondering if I'm just piling in on the hype or if it is truly something special compared to the list of bargain effects units I already have.
Old 24th June 2020
  #160
Gear Maniac
 
Mr. Syc's Avatar
 

I haven’t tried a lot of those other FX but I do feel like Ensoniq has a distinct flanger, that’s one reason I own one. What’s that worth? I don’t know, not $500. It’s also kinda huge
Old 29th June 2020
  #161
Gear Maniac
I convinced myself to buy one. Someone in the comment section to Espen Kraft's youtube review mentioned that spending about $100 per channel for effects is a good rule of thumb.

So $100x4 for 4 channels of effects was the justification I needed.

However, I ended up paying about $450.

The Ensoniq DP-4 is lighter weight than I expected. I expected it to be heavier. It's a large box (depth in the rack) with a large motherboard inside, but not stacked with lots of heatsinks and heavy parts inside.

The screen, at first, flickered a few times, showing some signs of erratic behavior that ensoniq is notorious for. After a little bit of warm up the screen settled in fine. Could be a loose ribbon connector or a very early sign of a power supply needing to be recapped.

The effects sound great. I have several ASR-10's and it does give it a similar sound. For example, I like the 32 voice chorus effect (patch #46 ) and it sounds very much like my ASR-10. Yes. I realize that there isn't the A to D and D to A sample conversion going on.

The unit is indeed noisy. With no sound feeding through, with input and output at about 1 o'clock, there's a noticeable hiss/noise in the signal. I'm not sure how others deal with this. Also, if I power up the Ensoniq DP-4 after I've already powered up my mixer and amp, I get a loud pop turning it on. So the Ensoniq DP-4 is a picky device that needs to be powered up before the amp and mixer. Not sure, technically, why this is or how it could be modded and fixed.

With the noise, and the power supplies usually needing to be recapped, and some of the erratic behavior from time to time, it's hard to justify some of the nearly $1,000 prices I see online.

Even at $450 I feel like I splurged a bit. The good thing is that it will probably become my go to effects and probably be on often.

I did a side job yesterday and made about $150 for 6 hours of work. So I recovered a portion of what I spent.

Also, that's a good rule of thumb for some gear heads here. Try to support your hobby with supplemental income. Don't spend income from your regular 40 hour per week primary job. Make extra money on the side for gear and then you don't have to feel guilty about splurging time to time.
Old 2nd July 2020
  #162
Gear Addict
 
goodweather's Avatar
OK I also took the plunge
I missed the revised DP/4+ (I could discuss with the person who did the repair, was explaining all he did) but when coming back to the seller, the unit was gone (or he didn't want to send it).
Then surprisingly, the guy selling his DP/4 and that didn't contact me back waked up and after another month or two I got the unit.
I could only only test it functionally with nothing connected.

Was super happy till I connected it to my mixer send/returns... There is constantly a "siren" noise going up and down then silent for 1 min then coming back.
Hope that some of you can help solving this.

Some points:
- my DP/4 is from 1994-01-11
- I'm in Belgium 220V 50 Hz. The unit I bought is equipped with a big external transformer 220-50 to 120-60. Can someone confirm that units sold in Europe are delivered like that? I mean the DP/4 is in 120V 60Hz but supplied with that big transformer. Maybe that I have an US unit that someone brought and not an Europe one
- the room where I have my gear is not equipped with earth (yeah, bad... old house from the end of the seventies)
- I will redo a test in another room with a separate modern electrical network (and of course earth) and let you know the result

Some question then:
- how can I test the audio out of the DP/4 without any headphone? Is the only way to use a mixer and powered speakers? Don't want to move all my stuff to that other room ;-)
- what could that noise be related to?

I will of course also re-contact the seller but he told me that everything was working fine and just didn't know if the unit has been restored.
Paid 500 EUR which is on the high side for a DP/4 here in Europe. Don't want to feel this wasted and still very eager to have a nice DP/4...

Thx in advance!
Old 3rd July 2020
  #163
Lives for gear
 
Bignatius's Avatar
Only the 4+ has CV, right, not the 4 or 2?

I barely missed a sale on a DP/2 the other day for $275. That seemed fair/a decent value.
Old 3rd July 2020
  #164
Lives for gear
 
aleyas's Avatar
 

Quote:
Originally Posted by Bignatius View Post
Only the 4+ has CV, right, not the 4 or 2?

I barely missed a sale on a DP/2 the other day for $275. That seemed fair/a decent value.
My DP/4 has a CV input. Lucked out on it for $125 locally about 5 years ago. I’d probably pay up to $300 for another one, but I don’t think I’d jump on a DP/2 for that price. Ymmv of course
Old 7th July 2020
  #165
Lives for gear
 

Quote:
Originally Posted by aleyas View Post
My DP/4 has a CV input. Lucked out on it for $125 locally about 5 years ago. I’d probably pay up to $300 for another one, but I don’t think I’d jump on a DP/2 for that price. Ymmv of course
DP4 has a cv/pedal input
Old 14th August 2020
  #166
666
Lives for gear
 
666's Avatar
I just got a DP4 and i'm very excited to run it through its paces. Just put a Linndrum through a patch called Fast Gates and holy smokes it sounds amazing. Just sucks the gaps out and adds a little weird shine to it. Already love it!

Few issues & Questions;

Input dial is broken off, but I have a replacement potentiometer so that's all good
Output 4 doesn't work. Inputs all work and all the other outs work. Is this a common problem? Easy fix?
Any tricks to getting the silver Input / Output knobs off? dont wanna break off any more shafts.
Is there any good patch editing software?
Old 16th August 2020
  #167
Introductory guide

I don't think H3000 have become more affordable lately ... just as the prices of DP4's have started to go up, H3000's have appreciated by greater $$ - some people are asking $2K for them now.

So, I've made an introductory video for the DP4, to hopefully give people the lay of the land with this unit. For experienced users this is probably all a bit basic, however for people who want to know how it works and how to get around it, this will have something for you. https://youtu.be/ooE1Y9C1Qtw

I've also made a very short 3 minute primer here: https://youtu.be/L4La3xaakLU

I'm still working my way around video production and presenting, so be gentle!
Old 16th August 2020
  #168
Quote:
Originally Posted by 666 View Post
I just got a DP4 and i'm very excited to run it through its paces. Just put a Linndrum through a patch called Fast Gates and holy smokes it sounds amazing. Just sucks the gaps out and adds a little weird shine to it. Already love it!

Few issues & Questions;

Input dial is broken off, but I have a replacement potentiometer so that's all good
Output 4 doesn't work. Inputs all work and all the other outs work. Is this a common problem? Easy fix?
Any tricks to getting the silver Input / Output knobs off? dont wanna break off any more shafts.
Is there any good patch editing software?
Hi 666 - when output 4 isn't working ... are you in 4 source mode - ie: all four units are working independently and you are running an input into input (unit) 4?

If you are doing effects on a single source with all four units (ie: input 1, or 1 and 2 for stereo) then even though all units are working, the effects will come out in stereo through outputs 1 and 2.

Cheers,
Jules
Old 17th August 2020
  #169
666
Lives for gear
 
666's Avatar
Quote:
Originally Posted by jrakarl View Post
Hi 666 - when output 4 isn't working ... are you in 4 source mode - ie: all four units are working independently and you are running an input into input (unit) 4?

If you are doing effects on a single source with all four units (ie: input 1, or 1 and 2 for stereo) then even though all units are working, the effects will come out in stereo through outputs 1 and 2.

Cheers,
Jules
Hey Jules,

Yeah I was testing the in outs for each channel so was going into input 4 and output 4. I was running it so each channel had an independent effect. Input / output 3 was working so I don’t think it’s the stereo out issue. Granted, I’m very new to the unit so I could be missing something. I’m going to go through your video, amazing timing!
Old 17th August 2020
  #170
666
Lives for gear
 
666's Avatar
Anyone have any tips for removing the silver knobs safely? Don’t want to break any more pentiometer shafts
Old 17th August 2020
  #171
Quote:
Originally Posted by goodweather View Post
OK I also took the plunge
Was super happy till I connected it to my mixer send/returns... There is constantly a "siren" noise going up and down then silent for 1 min then coming back.
Hope that some of you can help solving this.

Some points:
- my DP/4 is from 1994-01-11
- I'm in Belgium 220V 50 Hz. The unit I bought is equipped with a big external transformer 220-50 to 120-60. Can someone confirm that units sold in Europe are delivered like that? I mean the DP/4 is in 120V 60Hz but supplied with that big transformer. Maybe that I have an US unit that someone brought and not an Europe one
- the room where I have my gear is not equipped with earth (yeah, bad... old house from the end of the seventies)
- I will redo a test in another room with a separate modern electrical network (and of course earth) and let you know the result
You must always earth your unit and provide it with the power it expects. The DP4 shipped with EITHER a transformer for 120v (in the US) OR 240v (in Australia). Even though you are in Europe, I do not believe any unit came with a universal transformer like you are describing.


Quote:
Originally Posted by goodweather View Post
Some question then:
- how can I test the audio out of the DP/4 without any headphone? Is the only way to use a mixer and powered speakers? Don't want to move all my stuff to that other room ;-)
- what could that noise be related to?

I will of course also re-contact the seller but he told me that everything was working fine and just didn't know if the unit has been restored.
Paid 500 EUR which is on the high side for a DP/4 here in Europe. Don't want to feel this wasted and still very eager to have a nice DP/4...

Thx in advance!
You should be able to test your DP4 with some standard phone plugs from the output of the unit to the phono (unbalanced) inputs on your sound card.

Without getting clean power into the unit and having it confirmed that the unit is getting the correct voltage that it expects, its very hard to diagnose issues. We're also not sure what your set up looks like, so it could be anything related to the rest of your set up.
Old 17th August 2020
  #172
Input output shafts

Quote:
Originally Posted by 666 View Post
Anyone have any tips for removing the silver knobs safely? Don’t want to break any more pentiometer shafts
There are two grub screws on the underside of each knob, which need to be loosened in order to take off the knobs. Looking at them, they look like very small alan-key style grub-screws.

If you loosen both of them, you should be able to slide the knob off relatively easily.

Approx 1.55mm hex/alan key - I've just done this on mine to make sure I know what I'm talking about. It wasn't an issue at all. They're nice and loose once you undo those two little grub-screws.

Last edited by jrakarl; 17th August 2020 at 06:12 AM.. Reason: additional info and test
Old 19th August 2020
  #173
666
Lives for gear
 
666's Avatar
Thanks! Mine dont have any screws, the large knob does but not the 8 input & output knobs. They must just pull off.

Been spending some time learning this thing and holy smokes it's great! Such a great sound for an old digital box. Wasn't really expecting too much but i'm beyond happy with it.
Old 19th August 2020
  #174
Lives for gear
 
Barfunkel's Avatar
 

Quote:
Originally Posted by 666 View Post
Thanks! Mine dont have any screws, the large knob does but not the 8 input & output knobs. They must just pull off.

Been spending some time learning this thing and holy smokes it's great! Such a great sound for an old digital box. Wasn't really expecting too much but i'm beyond happy with it.
Yeah DP/4's are great. Shame about the current prices, I think I paid 200€ for my unit (which I have since sold though). If I was still mixing OTB and wanted quality effects without the budget for a high end Lexicon or Eventide, Ensoniq's would be a good choice.
Old 19th August 2020
  #175
666
Lives for gear
 
666's Avatar
Quote:
Originally Posted by Barfunkel View Post
Yeah DP/4's are great. Shame about the current prices, I think I paid 200€ for my unit (which I have since sold though). If I was still mixing OTB and wanted quality effects without the budget for a high end Lexicon or Eventide, Ensoniq's would be a good choice.
Yeah a H3000 is my dream digital box, but this one fell in my lap for a good price. The 4 in & out makes this really unique. That Funk Phaser & the delay options are great!
Old 19th August 2020
  #176
Gear Addict
 

Quote:
Originally Posted by Don Solaris View Post
You know what's really sad...

I know exactly what each portion of this circuit board does. I've learned it the hard way. Few years ago, I've recapped my unit's PSU with slightly larger caps and kinda forgot about it. Sverel months later started using it, noticed a constant choking in the reverb feedback path if the reverb was longer than 5 seconds - it was driving me crazy. I tried everything to fix it, then one day i swapped capacitors to original value, and BAM! machine suddenly no longer had any choking in the reverb.

In other words, i was trying to service a fully functional unit for one good month and in this process i have learned how it works. I can now repair pretty much any DP4+, except i won't do that since i don't do repairs.
I'm really interested in why the larger PSU caps would have such an effect on the reverb feedback path. I'm kind of scratching my head as to what kind of design they went for that larger PSU caps (I am assuming the filtering caps) could affect the logic DSP.

You can get into as much technical detail as you want, I'm fine with that.
Old 19th August 2020
  #177
Quote:
Originally Posted by 666 View Post
Yeah a H3000 is my dream digital box, but this one fell in my lap for a good price. The 4 in & out makes this really unique. That Funk Phaser & the delay options are great!
I have both and they're very different beasts, at least from my perspective.
The Phaser-DDL is an absolute gem in the DP4 I lost count of the number of awesome guitar solos that sound inspired. All Win
Unfortunately, my H3000 is hanging on start up at the moment. My PCM80 takes 5 minutes to get going! hahaha Lots of capacitor work to be done at my place!

Back to you - now you have a DP4 you will find months and years of exploration ahead of you. Happy lockdown - the best time of your life if you've just got a DP4.

Now , I've not forgotten your issue with the fourth effect. Is it unit D?
Can you confirm if the unit works when you have it in a single source config?


Quote:
Originally Posted by Barfunkel View Post
Yeah DP/4's are great. Shame about the current prices, I think I paid 200€ for my unit (which I have since sold though). If I was still mixing OTB and wanted quality effects without the budget for a high end Lexicon or Eventide, Ensoniq's would be a good choice.
Yes, the prices are getting higher. I can't see them falling really. I still put the DP4 up against most units including Lexicon and Eventide. Sure Lexicon reverbs have a sound of their own.. but so does the Ensoniq. It's not as refined to my ears but it has character.
Old 5 days ago
  #178
Here for the gear
 

I'm looking for a DP/4 for a decent price that will ship to australia!
if someone wants to sell to an aussie hit me up please
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