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?
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?