Musical Fidelity X10-D

[bob orbell]

Hi all, does anyone here use one of these, for thoughs that don't know, it is a buffer impedance matching stage using two ECC 88 tubes and a 12 volt AC supply. I have two of them and like what they do, but for some time I have had doubts about the half wave rectification for the heaters, the heater supply shares with the HT which is a two stage full wave voltage doubler, +30v -30v, half wave rectification is not only inefficient, but it also causes DC to flow through the transformer and can cause core saturation, so a few weeks ago I looked at this and thought, why not supply the heaters with AC, this I have done on both of my X10-D's and the diference is very clear to hear, with no hum at all, whats more it is so simple to do, produces less internal heat and give a cleaner HT. If any one want's to know how to proced, ask me. Bob