Old Mixer

[yayajohn]

I've had a Behringer MX8000 for almost 20yrs now, it's been good to me

Unfortunately it's been acting up lately. For a couple of years now i've been getting random lights flickering like all 24 channel green pan lights.
Now i've noticed an undesirable scratching noise emiting as well when it does this. My remedy thus far has been the classic pound on the front of the console with my fist and it goes away.......a temporary and not so scientific approach that apparently has finally caught up with me since it no longer seems to work.
So now the time has come for me to make a decision.
1. Attempt to repair it myself
2. Find the "needle in the haystack" guy who can repair it locally.
3. Sell it for next to nothing or dump it.

I have never popped the hood on a mixer like this so I was wondering if anyone could give me some friendly advise before I attempt to disassemble this.
How difficult will it be to take this thing apart to simply look at the circuits and maybe see what the problem is?

[Nestor]

Problem is that parts are difficult to find, if at all... I would go option 2 definetely, give yourself the peace of mind. We cannot learn everything under the earth. Do something and do it well, but don't do everything in a bad way, and nobody can do everything well. This is my understanding. If you like your old mixer and want to save it, do it through a proper doctor, but don't try to be a doctor just like that... my two cents

[Bud Weiser]

I've had a Behringer MX8000 for almost 20yrs now, it's been good to me


1. Attempt to repair it myself
2. Find the "needle in the haystack" guy who can repair it locally.
3. Sell it for next to nothing or dump it.

Behringer is one-way gear,- almost noone repairs it because there are so many SMD components you need a special and expensive SMD soldering station for.

Very qualified techs do service for my gear, all refuse repairing Behringer, Mackie and even a 4-channel Ashly Class-D amp.
Ressourcing parts is tricky too.

When I bought Behringer and/or Mackie from local shops and it failed, I had to bring it to the shop and even they have in-house service/repair, they send it back to the manufacturer.
In most cases complete circuit boards will be replaced then, no repair on component level.

So,- after 20y, I´d choose 3.) and buy a better mixer if you urgently need one.
Buy at least an Allen&Heath,- no Behringer or Mackie again.

Bud

[yayajohn]

Thank you Nestor and Bud. Worthy advise from the both of you.
Rest assured that if it comes to having to replace a part or doing any sort of soldering then it's definitely getting dumped. Probably not going to want to spend the money needed for a professional repair either since it's not a class A device and I'd probably be able to buy a good working used one for the same or cheaper.

Because I can clear the problem (albeit only temporary) by jarring the console do you think it might be something as simple as a loose part contacting one of the circuit boards?
Or a loose connection somewhere? Or perhaps simply clearing the dust or spraying some appropriate Deoxit type of spray?
Are most of these large boards easily accessible to get under the hood or is it a nightmare?
Wishful thinking on my part but i'm hoping it might be something simple.

[Nestor]

I think your ideas are in order, why not, it may be something simple, but you need somebody else to see it for you, someone with experience, then you will be able to judge easily what to do next.

[yayajohn]

LOL apparently i'm not alone in my methods. Scroll down to the last post.

http://music-electronics-forum.com/t15640/

I wonder if it might be the ribbon cables? That I think I can do unless of course they are proprietary.

[Bud Weiser]

Because I can clear the problem (albeit only temporary) by jarring the console do you think it might be something as simple as a loose part contacting one of the circuit boards?
Or a loose connection somewhere?

Well, the desaster is, it can be anything.

Cold soldering joint(s)
Ribbon cables
other parts failure,- also temporary only, possible temperature dependent too

So 1st, you´ll need schematics/service manual to sort out potential problems and isolate the issue.

I still own a Mackie VLZ 1604 where the left main bus temporary fails, sometimes completely or sometimes lower level only and introducing noises you described above too.
Since month, my techs and me we´re unable isolating the issue even we disassembled the whole thing 2 times and thought it works again,- then after days the issue came back.

According to ribbon cables:
Not everything is connected by ribbon cables even these are potential cause of failures.
In my Mackie, they only connect the channel-, subgroup- and main-inserts and these are connected to a patchbay which works, so contacts are closed w/ nothing inserted and the main left bus should work regardless of ribbon cables when L+R is routed in a channel.
Just only an example but Behringer copied Mackie in the 90s, isn´t it ?

It can also be a haircrack on the large main circuit board and the chance increases w/ the size of the mixer because 8 channels need less circuitboard estate than 32 channels p.ex..
Larger boards flex much easier.

Or perhaps simply clearing the dust or spraying some appropriate Deoxit type of spray?

I´m not a big fan of spray at all.
You might do the work cleaning pots and faders w/ compressed air and I made some good experiences w/ Teslanol T6 for rusty vintage (Allen Bradley) pots, but doubt that´s cool for cheapo mixer´s cheapo plastic pots.
It´s all temporary fixes only ...
Super 10 switch cleaner is good for switches and rotary encoders but agressive to plastic parts, so careful dosing rules.
Deoxid itself is top notch but small quantity for a high price,- and as I said, it´s only usable for the moving parts in a mixer or chip´s legs when socketed.

Ribbon cable might be socketed too, but the sockets themselves are soldered to the circuit boards, might have high count of very thin contact legs and all the components were soldered in one go during manufacturing process.
Now, w/ your soldering iron, you might damage more parts by heat just because your soldering job is slower and normal soldering is much hotter than SMD soldering which is hot air.

Are most of these large boards easily accessible to get under the hood or is it a nightmare?

The larger these mixers are, the more disassembling and re-assembling becomes a nitemare,- just because almost everything is on only one circuit board which fills the bottom of the case.

The main nitemare of these mixers is, you cannot remove just only one channel for repair, you have to disassemble the whole thing instead.
It´s the most horrible and most time cosuming job for service techs,- removing all pot caps, fader caps and switch caps, unlock all screws holding pots and sort all that s##t for later assembly.
Then take care for all the ribbon cables and pull out that big mainboard without damage and flexing, just only to find out it´s too big for your workbench where are all the tools you need already and so on.

When all channel LEDs flicker, it might be the PSU too ...
Does your mixer work w/ an external PSU ?
Maybe it needs to be recapped !

Wishful thinking on my part but i'm hoping it might be something simple.

In most cases it´s simple, but finding it isn´t.
Once found, it´s matter of parts availability and/or service friendlyness of the device.

How many hrs of work you want to invest for a 20y old Behringer mixer showing age issues ?
What do you think you´d get for it @ebay even it worked perfect ?
Possibly nothing because noone wants it anymore today.

I have 2 8bus consoles in the closet, more worth a restauration than any Behringer, Mackie etc. just because they are half modular and no SMD technology.
You can pull panels and each panel is four channels while under the roof, each channel is devided into 3 or 4 circuit boards, so you can restore/repair just only the EQ, the aux section or gain section and so on.
The PSU is separate 19" rackmount.
I have spare parts, complete channels, ribbon cables, switches, pots and a service manual and noone wants ´em even these are low noise and sum well.
These cost DM 10.000,- a piece in the late 80s, but the company went out of biz ...
When buying similar today it´ll cost ~EUR 15.000,- +++

Since all mix in the box it´s hard to find people buying (used) mixers.

The experts and pro studios want Neve, SSL, Big by Langley, Harrison ...

Bud

[garyb]

all the above is correct, but ribbon cables ARE a weakness on many of those Behringer and Mackie boards.

open the mixer up, put signal through and wiggle the ribbon cables. it's pretty easy to see if it's a bad solder or bad cable then.

[yayajohn]

Awesome! Bud, Gary thanks for the info!
Ack! I had not thought about having to remove all of the caps and faders.
I think this will be my last analog mixer. I just won an A16 Ultra on ebay so i think I will try and just use that and my Presonus Digimax as inputs.
Hard to abandon a piece of gear like this that I've had for so long and gotten so familiar with. I almost wish it would just have a hard failure but it sure is painful just leaving it at the county dump.

[yayajohn]

After a lengthy search, I have found this

http://xpmtl.net/sdiy/fixing-a-behringer-mx8000-desk/


The pic looks like that's the underside of the board. Can anyone confirm this.

If so then that may be my quick fix to try wiggling some ribbon cables.

[garyb]

yup.

they make the boards like that because it's cheap and compact. it's almost not worth servicing if you have a component fail. you can probably find a bad solder with some pressure(non conductive, so that you don't short anything!) and/or a magnifying glass.

good mixing boards that are meant to be serviced usually have each channel on it's own card.