Allen and Heath ZED12FX effects PCB connection

Potato Cakes · Mar 11, 2021

Hello, everyone,

I am looking to see if anyone here has an Allen and Heath ZED12FX that they wouldn't mind taking the underneath panel off and taking a pic of where the brown cable connects to the effects daughter PCB that sits on the channel boards. I have been modding/upgrading mine for fun (1000uF coupling caps, TLE2072A, fader make up amp adjust, etc) and somehow I wasn't paying attention when I resoldered the lead that provides voltage for the effects board and connected it to ground. It burned out the 10R resistor and blew a cap, which did what it was supposed to do. After I replaced those parts and connected it properly, it makes this snapping noise, like a clocking issue, but it is also has the effect following it. This tells me the effects part is working but there is a something else in the digital realm on that board that is not happy or was damaged. I have a replacement board coming but I wanted to double check what the connection should before I rewire it.

Thanks!

Paul

deveng · Mar 12, 2021

Check out my post here:
https://groupdiy.com/index.php?topic=76086.msg965825#msg965825

I was repairing a friends Zed and that brown wire to the Efx board was not even soldered when I opened the back!

I believe your power supply and Efx pcb is the same as the 16&22 boards. I uploaded the schematic in that post. So that light brown wire should go to the 10v pad labeled as P7 on the power supply. If you're talking about the brown wire connection on the Efx pcb, that I don't remember where it was soldered.

Regards,
Jeff

deveng · Mar 14, 2021

Paul,

Just remembered I took a picture of the EFX board for Ian. It shows the connection location of the brown wire on the EFX pcb! Same thread link as above. On this particular EFX pcb the wire is just above TP1.

Potato Cakes · Mar 14, 2021

deveng said:
Paul,

Just remembered I took a picture of the EFX board for Ian. It shows the connection location of the brown wire on the EFX pcb! Same thread link as above.

Thanks for the link to the pic! As I had mentioned I had reconnected to the point labeled SGND and I for reason jumbled the letters in my brain to interpret that as signal, which also doesn't make sense. I reconnected the board to that point in that picture but I think I'm sure that the DSP chip is now damaged. Hopefully I will receive the replacement board this week and confirm that this was the problem.

Thanks!

Paul

amfibee · Jan 10, 2023

Potato Cakes said:
Hello, everyone,

I am looking to see if anyone here has an Allen and Heath ZED12FX that they wouldn't mind taking the underneath panel off and taking a pic of where the brown cable connects to the effects daughter PCB that sits on the channel boards. I have been modding/upgrading mine for fun (1000uF coupling caps, TLE2072A, fader make up amp adjust, etc) and somehow I wasn't paying attention when I resoldered the lead that provides voltage for the effects board and connected it to ground. It burned out the 10R resistor and blew a cap, which did what it was supposed to do. After I replaced those parts and connected it properly, it makes this snapping noise, like a clocking issue, but it is also has the effect following it. This tells me the effects part is working but there is a something else in the digital realm on that board that is not happy or was damaged. I have a replacement board coming but I wanted to double check what the connection should before I rewire it.

Thanks!

Paul

Hi Paul,
I know its a long time ago but I need a new ZED 2 effects PCB for my ZED12FX. I bought this mixer via eBay with the knowledge it was u/s.
When arrived I found some missing and burned components on this PCB caused by misalignment on the distribution PCB, the screw was missing and the nut on the distribution PCB was not aligned with the hole.
It's hard to find the correct part number for the effects PCB. The p/n says AG7053_3 but I can't find it anywhere.
Where did you purchase your effects PCB?
I hope you can help me!
Best regards
Mark

Potato Cakes · Jan 10, 2023

amfibee said:
Hi Paul,
I know its a long time ago but I need a new ZED 2 effects PCB for my ZED12FX. I bought this mixer via eBay with the knowledge it was u/s.
When arrived I found some missing and burned components on this PCB caused by misalignment on the distribution PCB, the screw was missing and the nut on the distribution PCB was not aligned with the hole.
It's hard to find the correct part number for the effects PCB. The p/n says AG7053_3 but I can't find it anywhere.
Where did you purchase your effects PCB?
I hope you can help me!
Best regards
Mark

I purchased it from an Allen and Heath dealer and it came to me directly from the factory. Apparently the company will sell spare parts.

Thanks!

Paul