Step-Up Transformers v Phono Preamps

[MartinT]

With the o/p impedance of the PTG at 17 Ohm I think you need to lower your loading to 100~150R... 470/500 is too high IMHO and would lead to the symptoms you described.

Thanks Neal, I will try the preamp set to 100R loading, but of course I have no way of adjusting the trannie's loading which remains at 470R. So this is an experiment for the GCPH on its own.