Behringer ADA-8000 owners: PLEASE READ!!!

[moley1390]

Hi all,

Just wondering if anybody knows whether this is still a problem on newer units? I know there's been mention that significant changes have been made over the years (particularly regarding the opamps/converters), and was wondering if perhaps they'd attended to this? I know that the converters were changed around 2009, and this thread dates back before then.

Cheers,
Scott

 

[mnats]

Just wondering if anybody knows whether this is still a problem on newer units?

As stated in the first post the problem of transformer failure seems to be limited to those with 120 line voltage so if you're in Canberra there's nothing to worry about. But if you're worried about high secondary voltages just pop the cover and take some measurements to see if yours is similar or not.

The recent changes were pretty thoroughly described in another thread. A newer US model recently landed on my bench. It didn't have the fuse holder that allows the unit to be changed to 240V, but the transformer appeared to be the one described in the first post of this thread. The 240V tap had simply been terminated with an insulating cap.

When converted to 240V the secondary voltages were very high. I tried squib's solution (posted earlier in the thread) and that seemed to keep the regulators cool (while all the heat was being dissipated by the power resistor, of course).

 

[BYacey]

I bought mine new about 4 years ago, and they ran HOT right out of the box. What were the designers thinking?

I had a Hammond autotransformer kicking around, so I plugged all three ADA8000's into that and run the line voltage around 90 Volts.

 

[CJ]

hey  Bill!

thought you fell thru the ice,

 

[BYacey]

Nah,
The ice is gone for awhile; I've been here and there. Lately I've been focusing my energies on building a concert PA system. I'm just assembling the horn loaded subwoofers right now.

 

[EmilHarder]

I know this is an old thread. But I've just got one of these ada8000 from a friend. It appears that the transformer is burned. So I'm about to make a new external. Much like Michaels in #19.
I just can't quite find the power ratings anywhere.
The box says 250v, 25w, that's roughly 25VA (right?)
It also states that the fuse should be 350 mA. Wouldn't that make it 0,35x250 = 87,5.

I can't find anything about the stock tran.

Here, http://www.sawstudiouser.com/forums/showthread.php?t=11596, they talk about 15VA for the 2x15 and 30VA for the 2x22.

But first, I'm in Europe, second, I still can't find anything about the power rating for the 6v out.

I hope there's someone here who can point me in the right direction

Sorry if I'm wrong in every way, but I'm really lost about this.

 

[SSLtech]

Returning to add some more data:

I've got another dead-primary winding ADA-8000 here, and this time I found -as others have noted earlier- that there was a ceramic capacitor that had failed dead-short across the 48V windings...

So definitely unplug the transformer secondary plug from the board, and make sure that there are no shorted loads across any of the windings before continuing.

Other than that, there were NO shorted turns on the primary, just an open circuit 0-120 winding... -I was able to re-use the 120-240 half of the winding to get it working again.

Now to mod the unit to hopefully prevent this from happening again... but I did definitely find a shorted ceramic disc cap, and it didn't have any tell-tale discoloration. ALWAYS check with a multimeter before re-connecting the secondary.

Keef

 

[PRR]

> roughly 25VA (right?) ...fuse should be 350 mA. Wouldn't that make it 0,35x250 = 87,5{VA}.

Yeah, and I have 100 Watts of light fused for 2,500 Watts.

What's going to happen? *Usually* it either pulls happy current or it goes SHORT.

(See Keef's post; you can also have winding-shorts, rectifier shorts, etc.)

Short-circuit current is "infinite". You need a fuse. The exact rating isn't real critical.

Also 0.1A fuses are rare, fragile, and tend to blow on short-term transients which do not harm anything else.

There's an old-old LittleFuse ad which notes that most 1mA meters are not blown-up with 1.1mA or 3mA accidents, they usually die of BIG accidents. They rarely slow-cook, they usually get HAMMERED. They advocated 100mA fuses for 1mA meters.

The 0.35A fuse doesn't protect the transformer against long-term small overloads, true. But there probably isn't even 10 Watts load in the box. If current gets excessive, something is WRONG. The maker's best-bet at this point is to avoid burning the line-cord and endangering the user. 0.35A is small enough to blow before a line-cord gets hot.

 

[tgs]

I'll borrow this thread to ask about something that may not be totally related:

I have an ADA8000 that since a while back has some noise on all the inputs. It's not audible, but all the green LEDs on the front are lit up and it registers something like -85dBFS in the computer with nothing connected to the inputs.

Not that it really bothers me and I hardly use it either, but it would be interesting to find what the problem is. I'm a novice so I'm wondering if someone could nudge me in the right direction so I know where to start looking. And if I break the unit in my pursuit I will not cry either. 

 

[mobyd]

Another ADA-8000 related issue : What is going to happen to them now Wavefront/Alesis have EOL'ed the AL1201,1202 and 1402 chips upon which the unit is based ?.
M

 

[gemini86]

Likely will be replaced with microcontrollers or ADAT will be phased out entirely for USB systems. Pro level systems are more commonly using AES and the prosumer systems using firewire/usb.

 

[joaquins]

I have an ADA8000 original, but I'm in Argentina with 220VAC and the unit is 230V I guess because I don't think that B's guys uses a diff tx for us, so it guives me a 5% of margin more than you, in any case it still gets hot but never burned out. In any case wouldn't be easier and cheaper to add some turns to the pri of the tx instead of adding those big resistors and caps? maybe 5 or 10% of the turns and move to the next issue.

I didn't do any mods on it but I use to record the less critical stuff as reference tracks and some "less important" drums stuff. Now I'm changing my setup but I'm trying to move to 96khz so it isn't usefull anymore. (some places says that is work at 96 but you get multiplexed channels in pairs so the waveform looks like a nusty comb with a loooooooot of SF/2 content, I'd tried it)

JS

 

[andre tchmil]

Blown PT here. Can anyone tell me what is what on the sec windings.  I know it's 5V, 45V and 2x15 V , but would like to have the order/ color code on the PCB connector.

thanks

 

[andre tchmil]

Well well , I had an open primary winding at 230 side.
So one winding measured open, other was OK.
Now I did a quick and dirty fix. Took the one good 120V winding( think blue/red) connected this in series with a spare 120V primary trafo I had and I was up and running again.
I have somewhere 100V at the primary.
Interesting note: with my variac slowly raising AC the unit came to life at 65V. all functions working. I didn't took the time to measure sec. voltages.
Any comments on my hookup welcome, I have a session coming up in a few hours and want to use the ADA.
thanks

 

[lari]

hi everybody,
just trying to find appropriate replacement transformers.
wondering what should be the power rating and/or secondary current.
anyone from uk got any web links to specific transformers ?
would something like this be ok?:?
5v:
http://uk.farnell.com/multicomp/vtx-146-015-106/transformer-15va-2x-6v/dp/1675043
15v:
http://uk.farnell.com/multicomp/mcta015-18/transformer-toroidal-2-x-18v-15va/dp/9530274

cheers

 

[AUDIO FREQ]

I wanted to do this mod, but can't seem to find 10w or 25w in those ohm values at mouser.com.

There are some on amazon going at $15 each but I don't think that makes sense for me financially.

I guess we'll just be running hot!!!!

 

[Tubetec]

As far as I remember running the ADA8000 on 120v stressed things even more , but many still died with 230 v after a few years .
Swapping out op amps , you might be stressing it even further , maybe best leave the lid off for extra air flow .

 

[AUDIO FREQ]

As far as I remember running the ADA8000 on 120v stressed things even more , but many still died with 230 v after a few years .
Swapping out op amps , you might be stressing it even further , maybe best leave the lid off for extra air flow .

I haven't taken a look at the transformer yet, but maybe an appropriate transformer would be the easiest way to go for remedying the psu.

 

[Terby]

Mine died a couple of weeks ago (230V Version) - shorted ceramic cap on the secondary for the 48V phantom power supply ... now the transformer is dead. (one of the primary windings is open circuit)
I should have paid more attention to messages regarding this problem and have removed / replaced that cap in time ... so please do yourself a favour if you still have a working unit ... After a lot of research I have found a (hopefully suitable) replacement transformer - unfortunately without a 48V winding ...

 

[AUDIO FREQ]

Mine died a couple of weeks ago (230V Version) - shorted ceramic cap on the secondary for the 48V phantom power supply ... now the transformer is dead. (one of the primary windings is open circuit)
I should have paid more attention to messages regarding this problem and have removed / replaced that cap in time ... so please do yourself a favour if you still have a working unit ... After a lot of research I have found a (hopefully suitable) replacement transformer - unfortunately without a 48V winding ...

What cap would you have replaced it with? Something of higher voltage value but same capacitance?