Solid-State Versus Tube Rectification in Pre-amp Power Supplies

[Ron Resnick]

Regarding solid-state rectification versus tube rectification in preamplifier power supplies, have you noticed any correlation between a tube rectified power supply and a greater sense of weight or body or tonal density versus solid-state rectified power supply preamps?

What has been your experience?

 

[Mikerdaniels]

New owner of Cary SLP-5 no Ultimate upgrade.. It’s about 15 y.o. With a solid state power supply. Confused about tube power supplies .

 

[adrianywu]

Regarding solid-state rectification versus tube rectification in preamplifier power supplies, have you noticed any correlation between a tube rectified power supply and a greater sense of weight or body or tonal density versus solid-state rectified power supply preamps?

What has been your experience?

I think this really depends on whether there is regulation, and which type of regulation. My preamp has SS rectified B+ using Hexfred diodes, followed by a CLC filter, followed by a shunt regulator. I run the idle current of the shunt quite high, about 2x the load current. This gives very fast transient attacks and no dynamic limitations. One of the problems with tube rectifiers is the high source impedance. This tends to soften transient attacks and limit dynamics. This can be mitigated with a well designed regulator, but this makes using tube rectification pointless, other than its slow start characteristic. Fasting switching diodes nowadays like Hexfreds have no switching noise. In my opinion, tube rectifiers are best left for the vintage amps.

 

[Musica Bella]

I think this really depends on whether there is regulation, and which type of regulation. My preamp has SS rectified B+ using Hexfred diodes, followed by a CLC filter, followed by a shunt regulator. I run the idle current of the shunt quite high, about 2x the load current. This gives very fast transient attacks and no dynamic limitations. One of the problems with tube rectifiers is the high source impedance. This tends to soften transient attacks and limit dynamics. This can be mitigated with a well designed regulator, but this makes using tube rectification pointless, other than its slow start characteristic. Fasting switching diodes nowadays like Hexfreds have no switching noise. In my opinion, tube rectifiers are best left for the vintage amps.

I agree. It really depends on what you want to hear and how you hear it. I prefer the fast transient attack and dynamics of solid state power supplies. On the other hand, I have really enjoyed many tube rectified preamplifiers and have built both for customers. Always use at least a CLC configuration.