Step Up Transformer

Two different things. I think you’re referring to current driven phono stages that supply all the gain needed plus RIAA correction. There is a plethora of those. I’m talking about a current driven external gain-only device that does not supply RIAA or by itself is it capable of driving an amplifier or downstream linestage. It drives an MM phono stage. IOW it’s a head amp or pre preamp that works off signal current not voltage. I only know of one such commercial device, made by Sutherland.

The EAR ' The Head' SUT was made in a small quantity, which results in very small numbers of individuals that have experienced one in use. The idea they very rarely are seen as a used sale item suggests for most owners, these models are keepers.

Whether the SUT is kept for its sonic capabilities or the fact it is appreciating in value is one for the Jury to decide.

For myself, I have come to trust the assessments of my Local HiFi Group, especially with one member being a dealer in High End Audio and another a retired Hi End Audio Dealer, where each have /have had clients that are using six figure sum systems. I think their assessments are with a validity and ones I will not discount. The other members making known similar assessments only reinforce the overall assessment, of the impression 'The Head' has made.

I know a man who has no desire to part with his owned EAR 'The Head', they very much enjoy what it does, and have no doubts about what it does in comparison to a limited number of other SUT's, it has shared demo' time with.

As an alternative, the last one I had seen as a sale item, was with a £2000 asking price, which is a substantial appreciation in Value.

'The Head' is now a Legacy Item  and because TDP is known to be very closely attached to this design, they will most likely appreciate further toward the heavens, where TDP is at rest.

A SUT that I have been demonstrated recently in another System and have put it on my shortlist of Home Demo's 'to be had' when the system is back in use, is a selection of models produced by Sculpture A. I am feeling very good about having discovered this design and it is one of the rare items, I get compelled to want to experience in the home. The individual who supplied these for the demo' I was attending, has made it known, by the time I am ready for a home trial, the Company will have brought further improved New Models to the Market. I look for ward to seeing if these can be brought along to.  

@lewm thanks for the explanation, I wasn't aware such a device even existed.

I have a Cinemag 1254 based SUT built by Ned Clayton on eBay.  I find it to sound fantastic, and should be similar to one of Bob's Devices but is much cheaper.  It has 4 gain settings for ultimate flexibility, and 3 ground settings for the most quiet blackest backgrounds you'll ever hear.  I find detail and clarity and bass drive to all been kicked up a notch as opposed to going straight into my phono pre, which is quite hissy at high gain levels.  Now my MC setup is dead quiet, something I'm not used to, and paired with my old Koetsu Black, I am in vinyl nirvana.

Thanks Drew, I’ll check him out.