Mercury Magetics Transformers...problems, bad sound

[AG Amps]

The last batch I ordered had incredibly noisy power transformers. I ordered for four amps and they were all bad. I'm seriously considering the need to replace them before they go out to customers.

The filaments center tap can not be used as a ground in the 5e3 and these power transformers are noisy as hell. Normally you can ground both ct's or attach the filiment ct to one of the cathodes and this helps in a 5e3. The cheapo versions I use in other amps are quieter than Mercury now! It's progressively gotten worse and I need suggestions on a good, quiet power transformer replacement. I use another supplier, too, but was looking for other options out there.

[scole]

thats bad news, for fender amps i use allen, his are heyboer made to his specs, they'r very good.

[AG Amps]

I was just looking into Allen Amps. I noticed the output transformers are Heyboer, but not sure about the pt's. Either way, it looks like a good deal and I've used allen before and he seemed like good people. Thanks for the heads up.

[macdillard]

Musical Power Supplies

Go take a look at www.musicalpowersupplies.com. I have used his xformers, both PT and OT in 18 watt Marshall builds..Have not had any problems with them. Fellow's name is Matt. Well, did have one PT that buzzed. He took it back and replace it at no charge. You can hardly go wrong for the price.

[Bruce / Mission Amps]

Go take a look at www.musicalpowersupplies.com. I have used his xformers, both PT and OT in 18 watt Marshall builds..Have not had any problems with them. Fellow's name is Matt. Well, did have one PT that buzzed. He took it back and replace it at no charge. You can hardly go wrong for the price.

The prices are decent alright, most junk from China is inexpensive but cheaply made and questionable in quality. Especially after they start their little game of messing with your stuff until it fits their "minimum effort, minimum labor, minimum quality" needs.
Regardless, how do those cheap transformers really sound compared to the Canadian or American made ones he says they are like ... ie., Hammond, Mercury Mag, Lenco, Heyboer, Weber, Ceritone, TMI etc etc...?

From his website:

Typical Competitor Cross-Reference Transformers:

Hammond 125E Universal
Edcor XPP25 series
Mojo's 7000118 Marshall 18W, 781 Blues Jr, 773 Fender Dlx
Antique Elx TF49969 Blues Jr, TF41318 Dlx
Mercury's MAR18-OT, FBLJR-OM Blues Jr, FBFDR Dlx
Webers, Ceriatones etc

[Bruce / Mission Amps]

thats bad news, for fender amps i use allen, his are heyboer made to his specs, they'r very good.

I don't think Allen uses Heyboer for everything... although I do use Heyboer for my 6L6 amp's iron, based on what I see on his website, I think we actually use the same custom winder for quite a few of the other pieces.
Still very high quality iron but just not the "buzz word of the month" company name with grossly over priced and over hyped transformers.
You know who I mean too.

[macdillard]

What I have done with the MPS transformers in the 18 watt Marshalls is use the PT and then use one of the name transformers for the OT. in particular those that use to come from S2. I have tried one of the OT's and I couldn't tell the difference but then I am old and don't hear as well as some..I have no connection with this supplier, have just used some of them. There are a couple of threads over on the 18 watt board and on AX84 evaluating them if you want to take a read. Lots of MOJO around vintage transformers. I spoke with one of the techs at Hammond about their line of vintage replacement transformers that they just released and his comment was that the biggest problem they (Hammond) had producing the transformers was was making they as cheap as the originals and he was not talking about price.

[Arys]

Hi All

I had similar noisy problem with a MM PT DPT 240-M for my 5E3,except that CT filament was grounded due to fact i wired filament not as stock 5E3 (did not ground one of filament of heating) to be able to ground CT.

My problem was that if CT was grounded fuses were blowing.
After long research I found there was a bad cabling insinde PT (230VAC between CT and 6.3 Green wire).A shortcut or bad wiring between primary and secondary heating.I had long and many mails with MM techs,I sent it back to MM theys did good job to repair it for free.
Now I am using my MM PT in 5E3 using CT grounded I can tell you it is so quite not a single Hum.

Hope it will help.
Phil