Mackie ProFX v3 not outputting any signal what so ever

Ive been having several issues with my Mackie ProFXv3 since my purchase a few years ago.

Over the last year, the Phantom power in it stopped working consistently and causes mics to pop and lose all audio for periods at a time. (Solved this by buying a separate Phantom Power supply)
However come today I walk in and fine that I'm getting no monitoring output from the mic, and on top of that there's no audio from the computer its plugged into either, Computer recognizes its plugged in and is sending the signal to the mixer but Theres no output?
Break was not engaged, everything was in the spot it should've been.
I switched over to a spare Behringer Audio interface to test. and the issue is isolated to this mixer.
I would like to get this fixed, if anyone's got questions or advice Is appreciate shooting them my way!

 

I would start by checking whether there's anything from the main mix, or PFL/Solo bus, or whether it's just the monitoring.

If there's no output from any bus, then I would start with what's common to everything. The starting point for me would be the power supply. I would measure the voltage at various points in the circuit, and make sure they are correct. You'll need a service manual, or at very least, a set of circuit diagrams. Mackie are generally pretty good at providing these.

If the power supply volts are all OK, then you may have to start signal tracing, for which you'll need a signal generator and an oscilloscope. Without these, you'll struggle to find which part of the circuit is faulty.

Best of luck with the repair.

S.

 

I wouldn't even consider trying to repair it (and I repair audio gear for a living). Bin it. Buy a new one. I'm afraid modern (and especially digital) gear is not designed to be fixed but to be thrown away.

 

I very reluctantly tend to agree.

I repair vintage electronics as a volunteer, mostly stuff from the 1940s to 1970s, for a Museum in Norfolk, and although I would have a go at something like this, as soon as one gets to Surface Mount components, and stuff done in software, I tend to give up.

When one considers how much a Mackie or Behringer costs to buy new, compared with, say, a small Neve or Trident or Tweed or Calrec mixer from the 1970s, one sees that making something cheaper also makes it difficult if not impossible to repair, so throw-away.

The other side of this coin is that modern stuff is a lot more reliable than of old, one NEEDED to be able to repair the old stuff, but if one considers repair labour, even at Minimum Wage, repairing modern stuff ends up costing more than just buying another one, and skilled repair labour is a LOT more than minimum wage!

Anyway, to Snowglobe73, hope you can find the fault and keep the mixer out of landfill.

 

For best reliability and sound I would personally get the best built and designed analogue mixer from around '78 - 90 that I could get my hands on, with minimum quantity of channels I can get away with and best sounding EQ, and rebuild it with modern super spec op-amps and then re-cap it (to set it back to new in terms of known wearing components). Price and availability of pots and sliders would be the main concern!

You should then have a much better sounding, more reliable and easily serviced desk then any of the "usual suspect", made in China, (with SMD's and BGA digital IC's etc) items that are so cheaply available. There's a reason they're THAT cheap! 48 channel TOTR Neve etc desks were more than a house back in the day! They can be £250K plus S/H.....

If one must use digital then feed the output from this desk into an ADC (generally a "digital audio USB interface"). I strongly recommend something like a ReVox PR99 MkIII, 1/2 track, 15ips, as vastly preferable though!