Behringer X32 Rack power supply failure

[Ryan Buerge]

As a new user of Behringer's X32 Rack digital console at church, I was forced to switch to our old analog mixer last weekend, 45 minutes before service started. The X32 simply wouldn't boot, on the second occasion we were to use it, no less.
The problem was easy to diagnose once I had the cover off -- a resistor in the power supply unit had blown up sometime during the week (picture attached).

Firstly, I need to get my unit up and running again, and I don't know the value of the little ceramic capacitor sitting right beside the bad resistor (it burnt up too). Check out the attached photo -- it's the capacitor circled in red (C4); can anyone tell me what it's rated capacitance is? I want to fix it myself and soldering on a new component is not a problem. I don't have warranty, or patience for shipping.

What might be the reason for the meltdown? I'm not entirely sure what is the purpose of the parts that blew up, but I'm guessing it's an RC circuit for filtering or smoothing the current discharges from the very high-capacity capacitor beside it. The obvious culprit is a power surge, but I think that's unlikely because it was plugged into a surge protector, which in turn was plugged into a battery backup with surge protection. Maybe one of these things is just too old and manipulates the mains in such a way that the mixer doesn't like? This was the first time I had left the unit on all week, so maybe something in our wiring just wore the power supply out over time.
My confidence in the unit just sagged quite a bit considering this happened while it's practically brand new. Maybe this is just a fluke and the resistor was bad?

Looking into similar cases, it appears that the X32 Rack does not have a high failure rate, but most fails do stem from the power supply.
It looks like most of the time these power supplies fail because of the cheap electrolytic capacitors that are used. I've seen plenty of these accounts, but nobody with my exact problem.

https://photos.google.com/photo/AF1QipNWtlwa1tCtEtK-WGmiT-d8Lm6hDwtc3a9WSb_2

 

[Riley Casey]

You'll need a schematic to do this right. Replacing the resistor and the cap ( if the cap is in fact bad ) will simply burn the resistor again because something, probably a transistor or regulator chip has shorted and drawn excess current thru the resistor. You could hunt and peck thru the devices on the PSU and look for shorted devices but I wouldn't turn it back on after replacing such devices until I had checked against the schematic.

 

[Ryan Buerge]

You'll need a schematic to do this right. Replacing the resistor and the cap ( if the cap is in fact bad ) will simply burn the resistor again because something, probably a transistor or regulator chip has shorted and drawn excess current thru the resistor. You could hunt and peck thru the devices on the PSU and look for shorted devices but I wouldn't turn it back on after replacing such devices until I had checked against the schematic.

Very helpful and thanks.
Any ideas where such a schematic might be found? My search results only convinced me that these are precious secrets and might actually be illegal.

 

[Paul OBrien]

If the unit is "practically brand new" why aren't you filing a warranty claim?

 

[Roy Andrews]

As Paul said, might it not be under warranty if it is so new?
Edit: I see, you are a new user of the unit, the mixer isn't new. Got it. Sorry.

Regardless, I know you said "X32 Rack", however I was able to find this:

BEHRINGER X32 SERVICE MANUAL Pdf Download

View and Download Behringer X32 service manual online. 40-Input, 25-Bus Digital Mixing Console with 32 Programmable MIDAS Preamps, 25 Motorized Faders, Channel LCD's, 32-Channel Audio Interface and iPad/iPhone Remote Control. X32 music mixer pdf manual download.

www.manualslib.com

Which is the service manual for the X32 console version, and there might be some similarities in terms of some circuits and / or the power supply. It's a start anyway.

And yes, it's very unusual to find direct manufacturer downloads of schematics these days. Presumably to prevent making it too easy for competitors to copy proprietary ideas. Nice that a few friendly technicians out there post stuff on places like manualslib.

 

[Paul Lewendon]

I don't know if it's a cop-out excuse, but makes sense, I was told a few years back from a tech at a particular manufacturer that the reason they no longer publish detailed schematics, is it's basically a how-to instruction for dishonest companies that want to clone products.
Either way it makes it easier for them to just sell people a new board at high dollars, instead of repairing for cents.

 

[Rob Timmerman]

I don't know if it's a cop-out excuse, but makes sense, I was told a few years back from a tech at a particular manufacturer that the reason they no longer publish detailed schematics, is it's basically a how-to instruction for dishonest companies that want to clone products.

Yep, this is typically the reason that schematics are not published. Of course, Behringer of all companies is likely very familiar with that given their history

 

[Paul Lewendon]

Yep, this is typically the reason that schematics are not published. Of course, Behringer of all companies is likely very familiar with that given their history

I didn't realize they were guilty of that, not that I've been looking out for it or anything. Yes nothing worse that a hypocrite "How dare you do what I do"

 

[jose sallt]

I'm having an issue w/ my X32 Rack. This video was awesome and you seem like you really know your way around this unit! I'd like to connect and see if you may know what is causing my issue: The front panel lights and buttons are completely dead, display works though (not the buttons, just the LCD), and strangely everything else works as well. I can use an iPad that is still connected to control things but I can't use X32-Edit over USB as I cannot upgrade firmware because all the front panel buttons are dead. When it boots, it says 'rack: not found' and then loads into a screen and is frozen there. techzpod download mobdro

 

[Paul Lewendon]

I'm having an issue w/ my X32 Rack. This video was awesome and you seem like you really know your way around this unit! I'd like to connect and see if you may know what is causing my issue: The front panel lights and buttons are completely dead, display works though (not the buttons, just the LCD), and strangely everything else works as well. I can use an iPad that is still connected to control things but I can't use X32-Edit over USB as I cannot upgrade firmware because all the front panel buttons are dead. When it boots, it says 'rack: not found' and then loads into a screen and is frozen there.

Edit: I don't know if the original post was edited or I just didn't see it before, I see you found bad parts in the supply,
so my reply below doesn't apply, but is still good for other situations.
====================
I'm not sure if you originally had a link in your reply ? It's possible there's a defect in the board, but if you haven't already, I don't know if you can in its current state because you said buttons aren't working, but the best thing to do when things are acting strange on any unit with no solution, is to do a factory reset. If it's still acting up, at least you know it wasn't a setting or programming issue. It's possible yours might end up being a loose cable inside or something defective.
I did a quick Google search for resetting the Behringer X32 mixer

How do I restore my Behringer X32 to factory settings? - SweetCare

Note: Be sure to save any scenes, routing or other settings to a USB stick before proceeding. There are two ways you can restore your Behringer X32 to the Factory settings: Method 1 While the X32 is booting up and the X32 logo appears on the screen, press and hold the Scenes/Undo button until...

www.sweetwater.com

 

[Roy Andrews]

I'm having an issue w/ my X32 Rack. This video was awesome and you seem like you really know your way around this unit! I'd like to connect and see if you may know what is causing my issue: The front panel lights and buttons are completely dead, display works though (not the buttons, just the LCD), and strangely everything else works as well. I can use an iPad that is still connected to control things but I can't use X32-Edit over USB as I cannot upgrade firmware because all the front panel buttons are dead. When it boots, it says 'rack: not found' and then loads into a screen and is frozen there.

You don't really talk much about the condition of the unit, or it's age, but a few observations... these units are constructed from a bunch of boards which are linked together via ribbon cables. If you live in a humid climate and / or have bumped the unit around a lot, something may have become corroded or disconnected. Additionally, these units have horrible ventilation, no fan, and use components that are right on the razor's edge of being UNDERspec-ed for the application. The power supply is a known weak point, and like most modern electronics, the power supply does not just put out a single voltage on a single rail, it puts out 4 different voltages on various rails at differing current levels as appropriate to power different boards in the mixer. As such, a failure of one part of the power supply might leave some things functional and other things not.

Regardless, troubleshooting by a reasonably qualified technician is more than likely required.

I've attached a document that should let a decent tech repair the power supply, if that turns out to be the problem, despite the fact that no schematics are available to the public for the rack edition at this time. Credit: Electric Things

You can also find the X32 full 32 channel console edition schematic in one of my previous posts, and some of the audio boards are very similar in design to the rack edition, as it the support circuitry for the display panel.

Good luck!!