I remember in the mid 1970s when every tubemaniac started to yank out his tube rectifiers from his Dynaco amps and substituted solid state rectifiers because it was obvious that we were getting better bass could see less ripple on your scope, and you put in very high current diodes so you could use gigantic power supply capacitors so, again, you could have better deep bass fishing.

You will note all across America very few tube amplifiers that use tube rectifiers because that is so old fashioned, can’t create enough DC current for 48 output tubes, and cost more than solid state devices. This is not true for Japan.

I have been hammering out on in my writing that the meaning of the directly heated triode revolution is all about the return of King Tone, so you can understand why the best directly heated triode amplifiers do not, can not, use solid state rectifiers...even the superior Hexfred types. The reason is well known for this retro-coolosity: the harmonics of tube rectifiers are vastly superior to the harmonics of solid state rectifiers, which means that all solid state rectifiers produce very high frequency harmonic hash which pollutes the power supply with very disharmonic grunge...which you can hear.

This is also a reason why solid state amplifiers, which must use solid state rectifiers, can never achieve tonal eminence.

So what price do we pay for tube rectifiers? We give up some deep bass fishing and we get superior tone, and a very high degree of tuning.

This means that there are many variants of tube rectifiers. By substituting types and brands you can alter the tone of your amplifier, and this is a very good thing because it expands your ability to control your tonal destiny which is not possible with solid state rectifiers. In a 300 B amplifier, if you can’t afford different brands of tubes, you can afford different brands of types of rectifier tubes because they are relatively inexpensive. The combination of blending different type of input tubes and rectifiers is your freedom of expression.

Your favorite tube supplier and your RCA tube manual will guide you in the choices you have in tube rectifier substitution.

Of course the good news is that both Western Electric and KR are planning to release high current rectifiers which means that those multi-tube higher powered amplifiers will no longer have to suffer with solid state rectifier grunge.




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