Step Up transformer

Yes, you definitely would need a conventional voltage driven phono with MM capability in order to insert a SUT into your system. But the VdH Grail is reputed to be superb, so I don’t know why you’d even consider it. On the other hand, I personally have never heard the Grail or your system.

I have the VDH Grail SB transimpedence (current) phono stage to drop the noise floor, not sure if I have to purchase another phono stage (voltage) in order to try a SUT.

a SUT will not work with the grail.  Of morbid curiosity, a step down transformer will work and in theory give you more output when feeding transimpedance stages.  Want to try a 40Ω denon 103 with your current stage?  Run it into a 4:1 step down transformer and you net 4X the current and a 3-4Ω  source impedance.

dave

Cool idea!

But I don’t think the Grail lacks sufficient gain for the cartridges listed. The motivation toward a SUT appears to be purely to enhance SQ. Although mating a 40 ohm cartridge to the Grail may be a source of dissatisfaction to begin with.

Of morbid curiosity, a step down transformer will work and in theory give you more output when feeding transimpedance stages.  Want to try a 40Ω denon 103 with your current stage?  Run it into a 4:1 step down transformer and you net 4X the current and a 3-4Ω  source impedance.

Very interesting! Would the Grail have enough gain at 3 - 4 ohms to counteract the reduced ~ 0.06mV output at that point? And how does one calculate gain from a transimpedance stage - is it directly related to the source impedance? And probably also depends on real input impedance (not 0) of the stage.

this is one of those ideas that works really well In the simulated world where an ideal  2:1 stepdown nets a 2X increase in output voltage.  Real world reality of greater than 0 input Z of the current stage and DCR's of the windings makes the actual measured gain from a stepdown feeding a current stage a fair bit less than expected.  I did net about a 3dB increase in output from my one go at this with a 4:1 but the current stage was less than ideal.   I ended up going for a 1:1 at the input of the current amp since the possibility of DC offset from the complimentary Jfets I was using is a very real problem.

dave