Behringer ADA-8000 owners: PLEASE READ!!!

[Terby]

I have yet to build the new transformer (and eventually a new cap) in. I have seen photos of more recent devices that seem to use a film cap instead of ceramic ... maybe the high secondary voltage ~60V AC was to much for the poor little thing after all those years ?

 

[Terby]

... and yes, same capacitance - voltage rating of the ceramics are not labeled in my device, so ~100V will not hurt.

 

[AUDIO FREQ]

... and yes, same capacitance - voltage rating of the ceramics are not labeled in my device, so ~100V will not hurt.

This is good to know. Thank you.

 

[AUDIO FREQ]

Hey guys, I was rummaging through my bin of salvaged parts from broken electronics and I found this working transformer that I salvaged from a Presonus Eureka.

Would this be a suitable replacement that would better handle the power needed?

 

[AUDIO FREQ]

For anyone that is wondering.

I took my multimeter and traced where the secondary wires go.

ADA8000 stock power transformer 2ndary wire colors are

BROWN: 0
YELLOW: 7815
YELLOW: 7915
GREY: 317
GREY: 317
ORANGE - 7805
ORANGE -7805

Now if anyone can answer me, would this transformer work better to cool off the regulators working in 120v Primary?

Attached a picture

Thanks

 

[cyrano]

The transformer in the ADA8000 has a bit too high voltage. That's what runs the 78XX ICs hot. And if it's old, some of the caps behind the regulator might leak a bit.

Changing the transformer won't help if voltages are identical. The Presonus transformer seems identical?

Bigger heatsinks or a hefty resistor in series with the primary of the transformer seem easier.

Also, my later ADA8000s don't have it as much as the oldest ones. Of course, the problem is worse for 110V countries. I'm in a 230V region. You'll find all details in this thread.

 

[AUDIO FREQ]

The transformer in the ADA8000 has a bit too high voltage. That's what runs the 78XX ICs hot. And if it's old, some of the caps behind the regulator might leak a bit.

Changing the transformer won't help if voltages are identical. The Presonus transformer seems identical?

Bigger heatsinks or a hefty resistor in series with the primary of the transformer seem easier.

Also, my later ADA8000s don't have it as much as the oldest ones. Of course, the problem is worse for 110V countries. I'm in a 230V region. You'll find all details in this thread.

I read through all the pages, some suggested a transformer with a lower spec'd secondary. I thought this might suffice as it only has 8v for the 7805 5V, compared to the factory transformer providing 11V.
This one also has only 16V instead of the 27vdc of the factory on.

 

[Tubetec]

I found the regulators on the ADA 8000 and other Behringer digital stuff of the era to run hot ,
The SCR24/96,Rev2496 equally benefit from larger heatsinks on the reg's .

Worth re-itterating , the ADA-8000 PSU is shown to be marginal at 110v ,
dropping the mic pre sub board alleviates the PSU problem entirely , line in balanced .

 

[AUDIO FREQ]

I found the regulators on the ADA 8000 and other Behringer digital stuff of the era to run hot ,
The SCR24/96,Rev2496 equally benefit from larger heatsinks on the reg's .

Worth re-itterating , the ADA-8000 PSU is shown to be marginal at 110v ,
dropping the mic pre sub board alleviates the PSU problem entirely , line in balanced .

I don't use the mic pre-amps so this is good to know. I have the entire front board disconnected. I also desoldered the LM317 regulator entirely. I would like to run balanced line ins, would I just install and wire the female TRS connectors directly into the main board like this?

 

[cyrano]

I read through all the pages, some suggested a transformer with a lower spec'd secondary. I thought this might suffice as it only has 8v for the 7805 5V, compared to the factory transformer providing 11V.
This one also has only 16V instead of the 27vdc of the factory on.

I was a bit confused about your trannies. If it's lower voltage it should help. I just put a resistor in series with the primary if needed.

And like a lot of gear: don't stack it in a rack without some airflow...

 

[Tubetec]

That circuit is a slightly different version of the ADA8000 than mine ,
It should work like that but you will need to install coupling caps on the signal line ,

 

[mhelin]

Well guys... I went to have a look at finding a suitable transformer but then stumbled upon a random website mentioning the mod for the opamps and that he was going to mod his faulty ADA8000 since the power supply had burnt out. BUT he pointed out that it was down to a shorted ceramic cap (103 - .01ufd) on the 60V AC input from the transformer.

Low and behold on checking this cap, it was indeed shorted!! - I replaced it and so now no more transformer heating!

Just wondering (because I've got an older version of ADA8000 too) what is the said burned ceramic capacitor doing there on/over the 48V AC line (TX secondary)?

 

[AUDIO FREQ]

What would be an ideal transformer for this unit (US power standards)? Antek has a bunch of transformers for sale that are really cheap.

 

[kike]

Hi guys.
I have three ada8000 and I have build external power supply for all three.
I have put two toroid transformers 5vac and for 17-0-17vac, i dont need phantom.
When i connect all three of them to that box I get loud 100hz hum on every output channel.
It doesn't matter what order.
But when I disconnect one of them the hum disappeared.
Again, it doesn't matter witch one.
The two works without this hum.
Can someone tell me what to check?
Where did I go wrong?

 

[kike]

every output channel

I meant, on every input channel

 

[Rob Flinn]

Hi guys.
I have three ada8000 and I have build external power supply for all three.
I have put two toroid transformers 5vac and for 17-0-17vac, i dont need phantom.
When i connect all three of them to that box I get loud 100hz hum on every output channel.
It doesn't matter what order.
But when I disconnect one of them the hum disappeared.
Again, it doesn't matter witch one.
The two works without this hum.
Can someone tell me what to check?
Where did I go wrong?

Is the power rating of the transformer sufficient to supply all 3 units ?

 

[kike]

20VA 2X6V, - connected secondaries in parallel

50VA 2X17V - connected to have center tap

I think that the original fuse on the unit is 3.15A

Is that ok?
It doesn't matter if i turn the gain pots. Hum is always the same level.

 

[kike]

Ok, i have read somewhere if the secondaries are overloaded it produces hum.
But why 100hz, is it because of the twin secondaries 50+50?
Btw, i am in Europe.

So, how strong transformators must be to power 4 units?
What to buy?

 

[shabtek]

Maybe ground/0volt/chassis connection issue, ‘ground loop’ or missing ground

 

[kike]

To check if the brown wire is connected to chassis?

I haven't connected earth wire to chassis because it is external power, only wires from trafos goes to the unit

I think that ground loop would be 50hz, but I am no expert