Introducing Fujii Amplifier

Recently Mr hideo Fujii (Japan) are doing experiment about

Single ended valve amplifier with some special technical .

He said Amplifier with diode resistance loaded

He's calling "Mirror images drive" for valve amplifier.

(He is passed way on early 2006 so we can't to see any more

new his technical of electronics .)but I will introducing his technologies

around amlifiers to be good.

What effect has ?

Usually pentode valve originally have a non lineal distortion

when near cut off position under Ip – Eb curve each valves.

Generally Diode valve has no lineal resistance .many of single

ended valve amplifier has non lineal distortion and produce some

of 2nd harmonic. This type of distortion is under 3/2 multiple character.

Which meaning diode has 2/3 multiple character so when you have

to get output signal on plate,probably to get some no distortion signal.

Is idea of Mr hideo Fujii. He call it's Mirror Images Drive.

This idea produce around min 1/20 less distortion of general

pentod amplifier.(many DHT has lineal Ip-Ep curve)

Generally made up good amplifier with out minimal distortion by

some of NFB but this type of amplifiers does not need NFB.

I think good for use a parts of KT88(6550)SE Amplifier
so you can get clear sound from Power Penthode Amplifier.distortion are divided by 10 or more.

About Fujii Amplifier explane

The single amplifier accompanies the essential non-linear shape which is derived from 2/3 power qualities of input anti- output current of the vacuum tube. Some device as for the vacuum tube amplifier which is not 10% distortion is generated from 5 to generality. In case of the triode amplifier, it is possible to decrease the distortion rather by giving the load resistance of 3 times from 2 of the internal resistance which it has individually. And in the multielectrode tube doing the kind of thing generally, that it decreases the distortion, it is assumed that it is very much difficult. Generating the strain rarely with the driver tube, making the secondary distortion decrease which occurs with the output tube is usually done, but it is very much difficult thing, is, but it is reduction method of the distortion which is used generally. We call "offset of the distortion". It has been said Fujii the multielectrode tube input/output relationship is stipulated in gm. As for the multielectrode tube because it is the electric current output device, as for effective amplification constant being consistent, because it is gm, the quality which is obtained with that becomes 2/3 power qualities. It is assumed that it is difficult to escape from these qualities. It is to insert the element where the method Fujii devising here generates the opposite quality curve of 3/2 power qualities in the circuit. The equivalent diode of a triode is chosen in the opposite quality element. And that applying as the resistant element, being to devise that it denies 3/2 power qualities, it does. It is first to be announced to the Japanese technical magazine in 1994 by him. He has died in New Year 2006, it stopped impossible already to look at the vacuum tube amplifier of that original thought, but those where the information regarding many vacuum tube amplifiers is left very are important thing. As for also backbiting of the wicked road being heard it is fact in the people of part, but as for me as for the vacuum tube amplifier of that original thought you think that even from now on it keeps living somewhere of the world. The very regrettable person is thought the dying/fleeing paragraph is with. The 6L6GC single amplifier which is announced in 1994 is a result of decrease of the distortion of maximum of 20 decibels with this method. There are 3/2 power qualities in the equivalent diode of a triode. Being recent years, he all the vacuum tube distortion decrease drivers which abolish FET experimenting and succeeding. The advocate of the single amplifier of dream being not to be, does, that already new technology is shown in us but you try probably to leave on the eternal master and the edge of heart. Furthermore the vacuum tube which is used has recorded when the equivalent diode of a triode connection of 12AU7 has the best quality quality.

 (1)Use: Distortion decrease of acoustic amplifier of distortion reduction  like a 6L6GC beam valuves.
 (2)Transmitting tube use of multielectrode tube like a 811A SE

 Right now does not need push pull Amplifier.

By Lagarto san D.I.Y single ended 2005-2009 amplifier

Ref : Hi End Audio Radio Gijutsu magazine
February 1997
about how to build up 6L6GC and 811A Single Ended Amplifiers without NFB
by H Fujii
Hi End Audio Radio Gijutsu magazine
October 2005
4D32 Single Ended Non NFB Amplifier how to build up
by H Fujii

Radio Gijutsu Audio Maazine by IA

Last up date 8thNov 2009    since Dec 2005

Hideo Fujii Ref from Science links.Japan