I did not believed it until I heard it with my own ears .Replacing the GZ34 with its equivelent 5AR4 on a300b SE mono bloc amp ,the high frequencies got metamorphosed,as if the tweeters were replaced by different type.
With this incontestable evidence ,you don't need to be a polytechnic graduate to understand that the choke inductor is the cupid . When the rectifier conducts to charge the input capacitor it grounds (AC) the inductor, paralleling to the output capacitor,hence high impedance tank notch gets created.Of course the 10henry and 47uf makes about 7 hertz but the rectifiers does not conduct continuously and the inductor is not 10 henry at high frequencies.By high impedance rectifier as tube, more damping is provided . Japanese even use serie resistors with tube rectifiers. (see Asno 2a3 Loftin White)
I did some trials (early 80's) using an "electrophone" amp (ECL82 EZ81) and the primary of a small ps trans. as choke, I reached to the conclusion that this phenomena occurs only if the output transformer is fed by low impedance ,triod or anode feedback, and above all ,without overall feedback .
You don't need to be the one who has invented the wheel to find that a doubler power supply is the radical solution for this problem . While the rectifier is charging one capacitor the other one is discharging in series with the choke , hence no more parallel tank resonator.
A few years later Jean Hiraga published a "hors-serie" of LED magazine untitled "Initiation aux amplis a tubes" .A total omerta about this subject , note that he does not use tube rectifiers in his realisations.But at the end of his book he added a precious collection of amp schematics, one circuit did use a doubler power supply in class AB amp.
Conclusion:
If you need to use choke inductor ,always use doubler power supply with semiconductor rectifier. http://www.ampslab.com/vintage_marantz9.htm
If you need to light a bulb in your power supply instead of a candle for saint Isidor ,stay in your faith to harvest a successful amplifier .
KOKORIANTZ
With this incontestable evidence ,you don't need to be a polytechnic graduate to understand that the choke inductor is the cupid . When the rectifier conducts to charge the input capacitor it grounds (AC) the inductor, paralleling to the output capacitor,hence high impedance tank notch gets created.Of course the 10henry and 47uf makes about 7 hertz but the rectifiers does not conduct continuously and the inductor is not 10 henry at high frequencies.By high impedance rectifier as tube, more damping is provided . Japanese even use serie resistors with tube rectifiers. (see Asno 2a3 Loftin White)
I did some trials (early 80's) using an "electrophone" amp (ECL82 EZ81) and the primary of a small ps trans. as choke, I reached to the conclusion that this phenomena occurs only if the output transformer is fed by low impedance ,triod or anode feedback, and above all ,without overall feedback .
You don't need to be the one who has invented the wheel to find that a doubler power supply is the radical solution for this problem . While the rectifier is charging one capacitor the other one is discharging in series with the choke , hence no more parallel tank resonator.
A few years later Jean Hiraga published a "hors-serie" of LED magazine untitled "Initiation aux amplis a tubes" .A total omerta about this subject , note that he does not use tube rectifiers in his realisations.But at the end of his book he added a precious collection of amp schematics, one circuit did use a doubler power supply in class AB amp.
Conclusion:
If you need to use choke inductor ,always use doubler power supply with semiconductor rectifier. http://www.ampslab.com/vintage_marantz9.htm
If you need to light a bulb in your power supply instead of a candle for saint Isidor ,stay in your faith to harvest a successful amplifier .
KOKORIANTZ