montesquieu
04-04-2019, 14:13
Really hesitant to sell this but the gap between what I got for the EAR 912 and the phono stage I have my eye on is substantial and I need to try and fill it.
For sale - the phono step-up transformer assembly that was made for me by Andrew Rothwell some time ago, using US-made UTC A12 transformers. There are cult objects in demand even over their Altec counterparts.
There are literally dozens of ways these can be wired between their primary and secondary coils, in series and in parallel, to deliver all sorts of results, but Andrew got out his slide rule and his oscilloscope to work out both theoretically (by ratio) and by measurement (to optimise the quality of the signal) the ideal way to wire them as a multi-option step-up. He then executed them superbly in a unit that gives 1:12, 1:20 and 1:33 step-up, covering the bases for the vast majority of cartridges out there from 40 ohm Denon 103 to 2-6 ohm SPUs.
The unit also has a bypass switch to enable it to be taken out of the loop if a MM cartridge is fitted.
All up, with the purchase of the A12s from the US, postage and tax, and Andrew’s time, effort and materials to do a custom job on these, I’m out a couple of hundred more than the £450 (including RMSD) I’m looking for for the unit. But I think that’s a fair price for a truly superb SUT that also (in my option anyway) also looks super cool.
There was a thread on this a while back - since then I’ve used it with a Technics SL10 / Technics EPC310 moving coil cartridge in the study, and in the main rig with my Miyajimas and with a vintage 1960s Alnico SPU. It matched wonderfully with the SPU. https://theartofsound.net/forum/showthread.php?59432-UTC-A12-microphone-transformer-as-phono-step-up-transformer Like all SUTs it repays careful placement, it worked silently after some trial and error in both my study and my main rig.
https://i.imgur.com/kTtIAaf.jpg
https://i.imgur.com/SPmvWZz.jpg
https://i.imgur.com/GsoeAdy.jpg
https://i.imgur.com/VQPtnTu.jpg
For sale - the phono step-up transformer assembly that was made for me by Andrew Rothwell some time ago, using US-made UTC A12 transformers. There are cult objects in demand even over their Altec counterparts.
There are literally dozens of ways these can be wired between their primary and secondary coils, in series and in parallel, to deliver all sorts of results, but Andrew got out his slide rule and his oscilloscope to work out both theoretically (by ratio) and by measurement (to optimise the quality of the signal) the ideal way to wire them as a multi-option step-up. He then executed them superbly in a unit that gives 1:12, 1:20 and 1:33 step-up, covering the bases for the vast majority of cartridges out there from 40 ohm Denon 103 to 2-6 ohm SPUs.
The unit also has a bypass switch to enable it to be taken out of the loop if a MM cartridge is fitted.
All up, with the purchase of the A12s from the US, postage and tax, and Andrew’s time, effort and materials to do a custom job on these, I’m out a couple of hundred more than the £450 (including RMSD) I’m looking for for the unit. But I think that’s a fair price for a truly superb SUT that also (in my option anyway) also looks super cool.
There was a thread on this a while back - since then I’ve used it with a Technics SL10 / Technics EPC310 moving coil cartridge in the study, and in the main rig with my Miyajimas and with a vintage 1960s Alnico SPU. It matched wonderfully with the SPU. https://theartofsound.net/forum/showthread.php?59432-UTC-A12-microphone-transformer-as-phono-step-up-transformer Like all SUTs it repays careful placement, it worked silently after some trial and error in both my study and my main rig.
https://i.imgur.com/kTtIAaf.jpg
https://i.imgur.com/SPmvWZz.jpg
https://i.imgur.com/GsoeAdy.jpg
https://i.imgur.com/VQPtnTu.jpg