Output Transformers......

[Monsta-Tone]

There seems to be this huge stigma with replacing a Mesa output transformer.

I've done it on several Mesa amps with great success, but the only one that was mine was a DC-2 that did not work when I bought it.
I got really curious today. My latest project, a 36 watt Marshall clone for telejas was in testing and I didn't really have much to do.
I have had an old DC-5 transformer sitting around for years, ever since I replaced the trannies in my old DC-5 with Mercury Magnetics.

I pulled the chassis on my Maverick which has been out on loan for a month and just came back today.
The OT was freakishly tiny! The original one was about the size of the replacement models that I put on 20 watt Blues Jr's.
I took a picture of it sitting next to the old DC tranny. A 50 6L6 output transformer has the same impedance as a 4xEL84 or 4x6V6 transformer.

Long story short, I said **** it and replaced the original OT with the DC OT.
All I can say is, HOLY FUCKING ****!!!!!!! Now this is a magnificent amp! It was terrific before, but WOW!!!!! Now it is extremely wonderful and large sounding with no farty distortion.



The reason I am mentioning this is that I got into a very minor argument the other day with a fellow board member who is also a tech. He emphatically stated that replacing OT's is just a waste of time. I have a lot of 1st hand experience with this, but never with an amp that I have used for months before making the change.
Notes just seem to jump off the fretboard. Harmonics are everywhere, the amp is much louder but much more pick attack friendly.

Here's a picture of the trannies side by side:

Electronically they are both about the same, but size truly does matter!

 

[Spewnz]

Nothing is taboo!!!......... awesome job.

 

[Heritage Softail]

Trannys are a big deal. Supposedly, one of the bigger diffs in the SLO and Hot Rods and other Soldano's that supposedly have the high gain channel of the SLO, is the De Young tranny over the Mercury Magnetics.

I kinda wonder what a De Young in a Mesa would sound like. Something for the Ampenstien Doctor to make come to life :shock:

 

[elvis]

It may not be the size, but rather the magnetics. One core may be saturating much more than the other. The characteristics you described seem to be largely transient behavior, and that would be affected most by the magnetics. It could also be a difference in inductance, but I suspect that any output tranny is rated for reasonable high frequency response.

 

[iamrobk]

Just wondering, how much do you think it all costs for a new one and installation, roughly? I should probably get a new one for my Nomad (read this thread if you care why, summary is UPS is terrible: http://www.forum.grailtone.com/viewtopic.php?f=4&t=42435). Since it seems like they can make the tone better, I figure that makes it easier to justify the cost (since it works fine...)