Behringer MDX2000 internal pics ?

I have a 2200, think it's similar?

nope, no daughter board. there's an echo in there, next to nothing inside.

no problem, i'm happy to give back in any way i'm capable.

Cheers

I have an MDX2000 with the daughterboard. There seem to be several different MDX2000 versions. Mine has DBX VCA chips. Unfortunately I don't have the unit here, it may take until next week before I can take a picture.

The later models don't have that daugherboard. The 2100 is a somewhat simplified circuit, the 2200 and 2600 models are SMD.

(there were several shorted ceramic caps on the main board also shorting the negative power... so the board could have shorted components)

Click to expand...

How did this happen? The only thing that I know of that will cause ceramic caps to short is a very-very-high voltage spike - like a lightening. And if that is the case, there may well be more wrong with the unit..

Jakob E.

I have seen a few of them , there are a few series of them with different vca and rms converters , the big(20 or 22 pin ic) is the behringer 2000 you also can use an SSM ic with the same pin out. The only problem is that i dont have the unit anymore.
For the rest you only have to change the ic on the vca line till the in/output , so only 2 or 3 ic's not the front side of that line because that is only envelope and has nothing to do with audio.
Then you can pull up the powersupply to +/- 18V.
The sound them is amazing!!!!!!!!

Oops, that reminds me. I forgot to take pictures last weekend. I hope I don't forget again.

Henk, the one I have has this circuit board. But it also has DBX chips (1252, if I remember correctly). So you say this subcircuit board is a replacement for an SSM chip? Do you remember the number. I wonder what it could be; the DBX chips are VCAs, as far as I know, not RMS detectors. Have to check again when I take the pictures...

Shorted power supply decoupling capacitors are a common source of failure in Bearstrangler equipment - especially in the big Eurodesk mixers. They are sometimes easy to locate as occasionally they are blackened - or have exploded!
Often not so easy though - it is then necessary to use a meter with a good low ohms range and probe around - until you get close, closer - then Bingo!
Not sure why they fail - surely Bellringer use best quality components don't they......?!!!
I guess that the reason we don't see FX units and crossovers for repair - is that they are so cheap they are just thrown away when they fail.....
Anyone seen any circuit, or schematic diagrams for Deadringer equipment?
When I once asked why they wouldn't supply documentation to speed the repair and aid support of their products - I was told that this would help other Companies to copy their products!
I actually laughed at them over this statement......!

I did find some paperwork , but i dont know if the serie that you have is the same.
So in the line from the vca is a quad opamp (TL074/84) and there are 2 NE5532 on that line .
Just replace them with better opamps (opa2604 , opa404)
For the BE 2000 I stil looking for what it was but i keep looking in my paperwork.

I finally got around to taking a picture:
www.andreashau.info/temp/mdx2000.jpg
Sorry it's not very sharp, but you can recognize how the subcircuit board is oriented.

Henk, are you sure you had NE5532s in your c*mposer? I've never seen any NE5532s in any B-unit. The older ones have BE027 and B037 opamps (I still don't know any specs on those), later they switched to 4558, 4560 and then 4580 chips. I put NE5532 in an older MDX2100 that had BA4558 opamps. The NE sounds much cleaner.

I just replaced a few of those 100n ceramic psu bypass caps for the opamps. I usually prefer Wima MKS-2. I measured those ceramics after I took them out and found that they all were below their ratings. Many of them were just above 50n!

Hey Rossi , I am sure that they where NE5532 , but my question to you is what is that small pcb on your mainboard?
I have never seen one like that. Can you make a schemo out of that because than you dont have to buy the BE2000.
In my few that is the place of the BE2000.

But on the photo you made you can easy see the vca + those opamps 2x8pin and 1x14pin ics.
They are the one's that i replaced.

So the chip was called BE2000? Didn't you say it was an SSM chip. From what I researched in the meantime it might have been the SSM2120. But I don't know.

I was just asking out of curiosity. My unit works fine, and I don't really need that chip.

I'm afraid I can't draw a schemo. Apart from the fact that I don't have the unit right here, the subciruit board is glued to the socket. From what I could see (using a mirror) this little board houses some opamps andone or two CA3046 transistor array(s) - the same stuff that's on the actual pcb of the 2100 model. So my theory is this: B used the SSM2120 chip as a level detector and had to find a replacement when it became obsolete. So they re-built the SSM circit on a little board that plugged into the same socket. When the MDX2100 follow up came out, they simply incorporated that subcircuit on the actual board. Much easier than this subcircuit construction.

Apart from that, my MDX2000 and MDX2100 are fairly similar. My MDX2000 has DBX1252 VCAs, the MDX2100 has (DBX compatible) THAT VCAs. But I've heard of MDX2000 that have aphex VCAs.

Could be the SSM2120 , dont know yet , but the ssm is much more expensive than a few ca3046's and other stuff.
So it must be a late version because it must always be produced cheaper than the last time.
But Rossi could you make a schematic of that board? than we all can see which one is better the BE2000 or this board of yours.
When not than please a better picture of this small board , is it single or dubble sided pcb.
If it is single we can make a pcb from the picture.

I'll try to take a picture next weekend, but I'm not sure it'll work out. As I said, the small board is glued to the socket. I'm not sure it'll come off without damaging the board or the socket. The MDX2000 board is double sided, I think the subcircuit board is, too.

Hey Rossi you must put in those capacitors on the right side of the pcb, they take care of the voltage on the audio part and MUST be in.
I do hope you get a nice picture of that small board and the place of which is what ic.
It will be an lot of work to get that pcb out , you have to get almost every screw out of it that is in it and then the work to get those leds in the front again is a lot of work.

Henk, I think you confuse me with the original poster whose MDX2OOO was broken. My MDX2OOO works fine, no problem. The only thin I did to it was exchange a couple of those 100n ceramics (local bypass caps) for Wima MKS-2, mostly for sound reasons. The MDX2OOO has many of those, though, and I got tired of it. The double sided PCB is pretty sensitive to heat. Pads tend to come off when you de-solder and re-solder stuff. I know you can't take out the big PSU electrolytics, I never had intentions to do so. I would like to exchange them for bigger ones, but they're glued to the PCB, and I don't know if I can find larger ones that would fit. At 2200 µ they're probably sufficient, anyway.

I know how to take apart B*hringer gear; in fact I do on a regular basis and have developed a routine. By now I could do it in the dark. Still, I have litte hope that I will be able to take out SSM replacement board without damaging it. I mean, if it's just for curiosity's sake, I'm not gonna take risks. I'm not sure anyone actually wants to rebuild this SSM replacement board. For new designs, the THAT 2252 is probably a better RMS detector chip to go with the THAT VCAs, anyway. From what I read on the web, the obsolete SSM chip must have been a difficult bastard. THAT has a design note on replacing the SSM2120 level detector, if you're interested: http://www.thatcorp.com/datashts/dn126.pdf

Hey Rossi , on the right side of the pcb (near the trafo) there is space for four capacitor , you must put them in!! Much better stability on the audio side.
The 2200uF are they on the input or output from the regulator?

I also have seen the dn126 from that but i do think that B# is using the ssm2120 different in the mdx because a lot of the connections are put to gnd. In the dn126 is that not the case.

The cost for an ssm2120 is about the $22 to $29.

AAaaahhh! Now I get it. Sorry about the misunderstanding. Why didn't I think of that myself! Yes I could put some caps in there.

The 2200u caps must be on the input of the regulator. On the regulator output there is a small electrolytic and a 100n ceramic (now WIMA MKS2). As I said, many of the 100n ceramics aren't even close to their rating.

The ones that belong in the empty holes are probably on the regulator output with some resistors inbetween. Actually, now that I took a closer look at the picture it seems those are 0-Ohms resistors. In that case, the caps that go into those holes probably shouldn't be too big. High capacitance on the output can irritate the regulator, from what I've heard.

Have you actually seen a source for those SSM parts? They have been obsolete for quite a while. But I'm not sure I wanna spend $29 (+shipping) on maybe improving an old B-box.

I am just back from holidays , so now i do have time again to talk about the mdx2000.
We just bought 2xmdx2000 , 2xmdx2100 and a xr2400 and we gone modify them like i told you before.
So i can tell in a few days how the look like and which rev the are.
Now i just mod a few mdx2100 , the are very different from the mdx2000 , no be2000 but two ca3046 in rev d , the envelope looks like the same but the ic's i have to change are 1x4558 , 1xba4741 and a be037 this has to be done twice (for both channels).
I ask a friend if he will make pictures of everything so everybody can see what rev the are.

After upgrading the mdx2100 and mdx2000 i have found somebody who made the pictures from the change we do.
The pictures are all about the mdx2000 and in the center you find eighter the BE2000 or SSM2120 , what i did not find was a board like Rossi's mdx2000 has mouted.
I did find boards like that on the xr2400 and xr2000 but not on the mdx2000.
I will try to put the pictures on a server so everybody can see what has to be done.