[Moved] Power Supply MX9000 +17 Question

[SteveHill]

[Moved] Power Supply MX9000 +17 VDC Question

I have a Behringer MX9000 400 Watt Power Supply which did what most of them do... blow out the LM350 on the +17 VDC side. I replaced all three LM350's with LM388T's, as well as replaced all of the Cap, Diodes, resistors and the LM317 and LM7818 power transistors.

The PS shows correct voltages of -17, +17, +48, +12 & +5 at the PS pin- out but when connected to the mixer, the +17 is absent. I have also checked to be certain there is not a loose and intermittent connection at the pin-out.

I have two MX9000 mixers with one good PS so I am able connect the good PS to either mixer and the +17 is present.

I'm thinking the +17 on the bad PS drops out once a load is put on it but I don't have the knowledge to understand what component might be causing the problem. I have replaced various newly install components (like the Cap's, Diodes and LM388T's) with other new components thinking maybe a new component might have been bad but so far... I have not been able to resolve the problem.

Also, the AC input voltages from the transformer to the PS board are present and correct.

Any suggestions are welcomed.

Thanks for your consideration,
Steve Hill

 

[Raza]

Re: Power Supply MX9000 +17 Question

Hi Steve,
If I send you the diagram of the supply, will it help you?

 

[SteveHill]

Re: Power Supply MX9000 +17 Question

It might help me. I'd appreciate it.

Thanks,
Steve

 

[Raza]

HI,
Here it is and hope it serves you in repairing your supply.
View attachment behringer_mx9000_sch_[ET].pdf

 

[shotgunn]

My apologies for resurrecting and old thread... I have an MX-9000 PSU that I upgraded the +/-17V regulators on. Upon powering up after the upgrade I am not getting the +17V supply rail. I measured the transformer and have all the proper voltages from it. Any thoughts as to what could be the issue?

This thread seems to be the same exact issue. What was the end result of this?

Thanx,

shotgunn

 

[SteveHill]

Ended up shit-canning Behringers' worthless fuggn POS power supply board and xformer. Replaced with individual +18 -18 +5 +12 +48 power supplies and have never had a problem since. I have three MX9000's daisy chained together so redid all of the power supplies (as described in previous sentence) and like I said, no problem after installing power supplies that can operate from ding to dong without burning out. Behringer customer support and tech center blows, to put it mildly. I would never (and have never) bought/buy anything from Behringer again but because the three boards work well for what I use them for... life goes on and all is well.

 

[Nick Falvo]

Steve, I just got an MX9000 for a SONG ($45 plus the 45 minute drive to pick it up) the power supply died and the guy couldn't find one... (probably because every single one made is either miraculously still working or dead (99% of them))

anyway - how did you go about replacing with individual supplies? if i were to find someone who could fabricate, or modify the board for me, what would I have to show/tell them? I did download the supply diagram from Raza....

now what do I do?

 

[SteveHill]

Hey Nick, just saw your post. Kinda' pressed for time right now but I'll check my files to see if I can find the info and diagrams for replacing the power supplies. They are in here somewhere. I bought the power supplies on eBay for under a hundred bucks per mixer. Installed them into the existing MX9000 PS cabinets hooking up to the cable connecting to the mixer. A fellow I know in North Caroline used the info to re-do his PS about a year ago. Just got an email from him last night saying all is well and never has had a problem since. He is looking to buy another MX9000.... don't want to sell yours do ya?

 

[SteveHill]

Nick, attached are pic's of the individual power supplies, pic's of their part numbers and a hand drawn pictorial of how to hook the stuff up. One problem you may experience, because you don't have the old Behringer power supply you won't have the quick disconnect cable from the PS to the mixer which has the color coded wires. Not a big deal because if you look at the schematic you previously downloaded of the Behringer mixer and PS, you can determine which pin on the mixer corresponds to the power supplies. I hope this is helpful. If you have any questions, just ask. I don't know it all but I'm happy to share what I do know.

NOTE: The individual power supplies are two Mean-Well +18 VDC 5.6A, one LET K70-48, 48 VDC 1.5A and one SNP 9063, +12 VDC 4A / +5 VDC 3.5A. You use two +18 VDC power supplies and by connecting them correctly you obtain the -18 VDC. Although the mixer has two LED's labeled +17 and -17 the mixer operates off of +18 and -18.

You don't have to use the exact same brands but this will give you an idea of what type of supplies you will need. Like I said, I bought everything on eBay for less than a hundred bucks.

 

[Nick Falvo]

I'd consider selling it, where does he live? I'm in the north-east but I gig from Boston to Baltimore.. shipping this would be crazy, no?

 

[SteveHill]

Yeah, he lives in South Carolina so shipping would be crazy but thanks for the consideration.

 

[projectandres]

Hi, I have a problem with my console and I need your help, the model is MX8000A but I think is equal to the MX9000, 4 wire power connector and desoldaron not be the order in which to go, you could help me?

 

[thedrums]

Steve,

I also have a MX9000 with a PS going bad. I like the rebuild you have done with yours and would like to give this a try but I can't seem to find the MeanWell +18 PS. Seems they have discontinued that model and a search online turns up empty. Would you have any leads on that PS or an equivalent model? How help would be greatly appreciated.

Thanks,

Gary Turk