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Sakuma's bleeder tubes and series connected transfomers

Hi!

I admire and respect Sakuma's work a lot. But I do not follow all his principles. I am seeking a different goal in terms of sound than him. He did inspire and influence me a lot though. For example with his use of DHTs as drivers and in preamps and with the use of power tubes as drivers.

As far as I'm aware he is not selling his amps. At least not at a scale which could be called commercial. Implying that there is a marketing agenda is therefor not justified. I also don't think that his use of Tamura products makes a noticable dent in their transformer sales.

As others have written, Sakuma is not stupid or ignorant. I am sure he had a good reason to do this and I would be interested what he had to say about it. If he wrote about it then in MJ magazine, to which I have no access.

Nobody out there who read about these circuits in MJ and can share what was written about them?

Thomas
 
I have read that he never courted followers for his designs, what he wanted to inspire in others is to guard against allowing today's, past or future 'conventional wisdom' from constraining your approach, to try things out even if they might be counter to what you'd expect, and ultimately tune your amplifier for you, for what you like. As I understand, the last thing he would ask is for anybody to build somebody else's amplifier.

I thought he is no longer with us though - does anybody know ?
 
Disabled Account
Joined 2004
That sounds good. To tell you the truth, I don't know much about him. I have no idea where his fame comes from. A flagship amplifier? Articles? I'd like to hear his system but that's not gonna happen. Anyway, those weird 'ideas' will remain weird ideas. I can't imagine anyone here trying them out.
 
Audio seems to have become like the art world: the value of something seems to depend on who did it, rather than any intrinsic merit of form and design. If I put out a circuit like that everybody would rightly (and very promptly) tell me it was rubbish. Far east guru puts out the circuit and everybody worships; they assume that their own concerns about it are merely a sign of their own ignorance of the deeper things of audio. "He must have had a good reason for doing it that way".

Someone once said "If you want people to believe a lie, make it a whopper!"
 
Hi!

Far east guru puts out the circuit and everybody worships;

Nobody worshiped these circuits and Sakuma is a very modest man who would not see himself as a guru. So why this angry attitude? Sakuma's circuits receive more cynical responses than worhsips. And guess what, he probably doesn't care.


All I was interested in was what he himself said about this, if anything.

Best regards

Thomas
 
Audio seems to have become like the art world: the value of something seems to depend on who did it, rather than any intrinsic merit of form and design. If I put out a circuit like that everybody would rightly (and very promptly) tell me it was rubbish. Far east guru puts out the circuit and everybody worships; they assume that their own concerns about it are merely a sign of their own ignorance of the deeper things of audio. "He must have had a good reason for doing it that way".

Three or four decades later, Tom Wolfe's _The Painted Word_ is more relevant than ever. But now, it applies to everything.

Thanks,
Chris
 
The "Teacher" Sakuma, said that: -for an unknown reason to me, adding irons betwenn the stages help the tubes sound better-. He uses series connected transformers to match the signal as he also uses series trans to achieve double voltage for the power supply.
This trick it really works and it sounds maybe better than single transformers do!
Becides we also do this to the electrical enviroments...
Of course there should be lots of theory arguments to this, but the fact is the transformer's action
and behaviewr differs at the working position, so please no comment to the subject.
Regards, Angelos
 
Hi!

I just browsed Sakumas website and found some of his latest works. Sakuma is known for his unconventional circuits. He added some new twists to his latest builds.

There are 'bleeder tubes' added to provide some load to the power supply. Probably for stabilisation. But why use tubes instead of a plain resistor? He even uses expensive DHTs for this purpose like a WE300B here:

12AT7 / 841 SE phono preamplifier

There is even a transformer added as a load to the tube, with the secondary just grounded on both ends.

Here he uses a 50:

5691 / WE-102D SE phono preamplifier

This time even with an input transformer.

There is probably some reasoning behind it, did anybody read the MJ magazines in which these circuits got published? Was there an explanation why this was done?

Also quite interesting the use of several transformers connected in series as a load to enable transformer coupling of high rp tube like the 841:

841 SE Tone control and buffer amplifier

Best regards

Thomas

Active hum bucking circuits. As to why Sakuma would use the audiophool expensive types for this makes no sense, especially when vertical deflection triodes, or pseudotriodes from the 6AQ5, 6V6, or other 6V6-oids, would work just as well for this purpose. Since he's iso-ing both inputs and outputs with ISTs, he could have gone solid statey here and used a MOSFET.
 
I'm with DF96 on this. The thinking that these circuits represent the discovery of some deep, unknown audio phenomena is total crap. This is the same kind of thing that sucks audiophools into spending $2000 on speaker cables, Shakti stones, and Bybee conditioners. :rolleyes: