VTL Transformer Up-Grades, Worth It?

I own MB-185 Signatures, which already come with the upgraded transformers. While I haven't heard the older versions without the Signature tranny, I have heard their current stereo amp offerings, which also lack this feature, and have found them to sound very good in spite of the supposedly "inferior" trannies used. However, I did read a lot of what was written critically about VTL's amps over the years when researching the line, and most reviewers seemed to be unanimous in crediting the upgrade with improved sound at the time it was introduced. Luke Manley certainly promoted the Signatures as being a big step up for his company, but that could always just be marketing. BTW, are you also thinking about getting the coupling cap upgrade? I am considering doing this, since I may send mine back to the factory for other service as well, but I haven't decided yet - it's fairly expensive. (Oh, and make sure to have your B+ fuses and holders uprated to the current-production 600v type while you're at it; the old 250v type is not adequate protection.)

Marakanetz - I think what you are referring to is the current range of VTL models that are made with this transformer (the Signatures and the References). They do, as far as I know, offer this transformer upgrade to be retrofitted at the factory for certain older models which originally were manufactured with what VTL feels were lesser output transformers. I am not sure off the top of my head which models VTL offers this upgrade on, but I do remember seeing the list on their website.

Jimmy - Just to reiterate, the upgraded transformers we are talking about here are the output transformers, not the power supply transformers, although that may also be a possibility for some of VTL's older models, which as I recall had a reputation for developing power transformer hum until they changed suppliers at a certain point. Also, all the VTL models had B+ fuses, but until recently they weren't high-rated enough to protect the circuitry under all failure circumstances. If you do send yours back to the factory for upgrades, they will also recommend that you have those fuses and holders updated as I described above. BTW, care to tell us what you were using before to drive your Maggie's?

Great! Did you do the coupling caps?

At least in the current editions of those amps, there seem to be significant differences between the two brands not only in the output tube compliment, but also in the driver arrangements, as well as the output transformer designs. In addition, the VTL has a lower amount of feedback applied, and a correspondingly higher output impedance. While they might both be inspired by David Manley's original VTL designs and look quite similar, I wouldn't expect them to necessarily sound the same.