Need help on Power supply!! for DDA console

The Transformer in my Console Powersupply are making some noise when it is on, is that mean it is no longer good? now I have to disconnect half of the total strip on the console to be able to get it fully power-up , btw: it is a 15years old DDA DMR12 , if I have to replace the transformer in it , can I have it replace with a bigger WALTs also I had replaced everything in it already accept the TRANSFORMER, ( the big round metal )
Thanks a lot everyone!

Acoustic vibration noise from power transformer CAN be normal.

But you can't be sure unless you get the psu checked up - it might be bad capacitors, pass elements, or rectifiers.

Power transformers rarely (if ever) fail gradually.

Jakob E.

The guys who were DDA around 15 years ago are now the guys behind Audient
Send an email to Dave Dearden at Audient and ask nicely if they can help.

well it happend after I had Overhaul the console with all brand new CAPs and Replaced all IC from 5532 or 072 to OPA2604 and AD826 ...
I also Overhaul the PSU everything including Increaseing the Big CAPs ...
It worked well for a month or so , then it wont fully power on , is like lack of standing current now I think it could be the ( Big Caps ) are failing cause it was taken out from my OTARI Open Weel PSU , also found the TRANSFORMER is make a Buzzing noise like it never does before , but after disconnect all strip and putting them back one at a time , it worked all fine when only total 24ch are installed and connected but once you put in the 25th strip it fail again ... no matter witch stip ...so I think it is only pumping out half the Juice now... its kind of like a Car power amp cranking Loud with out adding enough CAPS to support the sucking of juice...... I think I will try to replace the BIG CAPS inside and see what happened first..... :?

likely you have reached the limits of the trafo. time to upgrade the PSU.

do a search for all the warnings of blindly changing all opamps without checking the PSU too..

Is there a way you can measure current draw?
Maybe a reg is shutting down with strip #26.
Sometimes a power trans can rattle when un loaded. The low freq 50/60 cycles tends to pull lams togther magnetically, which means less noise.

To see this, take a C core or just some lams and put it over half a 120 line that is pumping current.

It can be hard to pull apart a core sitting in some flux.

Just an anecdote from a Soundcraft console, but a few months ago we had the PSU start make acoustic noise - a buzzing sound. Not long afterwards, one of the bridge rectifiers shorted out. My theory is that before completely shorting out, the rectifier was causing abnormal current draw from the transformer - hence the "heavy load" buzz it made. After I replaced the bad rectifier the PSU was completely fine.

I am still in searching for a new and bigger CAPS at the moment and also Have People Custom build me a bigger transformer as well , I checked every single strip they are individulely all right by them self ...
well I still remember Last time the regtifier fail it will keep POPPING the fuse , I will try to swap the rest out and upgrade everything to a bigger value to see rather or what is failing...
at this moment any info are gold ...
thanks for helping me

FYI: I replaced the BIG CAP and the rectifier in the PSU, from 4x10000uf to 2x33000uf then the Rectifier to a 50a-1000v , then the Console work just fine and perfect again also the Buzzing Sounds on the transformer are gone... so I guess the problum is fix for now ....I hope i am doing the right things :?

[quote author="Adky"]FYI: I replaced the BIG CAP and the rectifier in the PSU, from 4x10000uf to 2x33000uf then the Rectifier to a 50a-1000v , then the Console work just fine and perfect again also the Buzzing Sounds on the transformer are gone... so I guess the problum is fix for now ....I hope i am doing the right things :?[/quote]

It's hard to argue with success. Congratulations!

Thank you so much,
I just want to share my experience with the over swap IC and PSU relations, I think what ever inside the PSU originally is design for the original stuff so if any mod to them also need to mod the PSU as well, also what ever parts are in the PSU is old anyway they cant handle all those increased load, I am still waiting for the new Transformer to be finish so If i put that in then it will be a total bigger and newer PSU all together
Hope this time it wont fail on me again :?