Hiraga The Monster...

[grataku]

Originally posted by P.Lacombe
I don't agree with Mr Pass : substitution of transistors is a very complex problem in the Monster, to day's transistors are not made with the same processes and exhibit different transfer characterisics, internal capacitances, phase lag and so on. As far as I know, internal Ccb variation vs collector voltage, and Rbb' are essential parameters.

Jean Hiraga has invested a considerable amount of time to tune up this amp, not only with measuring equipment, but also with ears and brain. Some particular choices results in a specific distortion cancellation, which can be totally ruined by substituing transistors. (The same occurs in valve amps).

I presume that the correct answer is to entirely redesign the whole amplifier with available transistors... This is (verbatim translation from french !) a monk's work !

Regards, Pierre Lacombe.

I think all the above is just crap. There are much better semis today than there where in the early 80s. It's much easier to get gain matched devices with pretty much any capacitance you wish. The design is not -that- complicated to justify such self indulgent claims. I believe in my version all these factors were considered.

[Steve Eddy]

Originally posted by grataku
I think all the above is just crap.

Yeah, I kind of get the feeling it's just an attempt to maintain some sort of mystical aura about the amp and its designer.

And you know how touchy those French are about heathen Americans meddling with their cultural icons. Jerry Lewis notwithstanding.

se

[fdegrove]

Hi,

And you know how touchy those French are about heathen Americans meddling with their cultural icons. Jerry Lewis notwithstanding.

For the record the amp originates from Japan not France.

Quite likely the transistors can be replaced with modern ones.
Twenty years ago that wasn't all that simple though.

Cheers,

[Nelson Pass]

OK, I just can't stay away from this....

The problem as I see it is not that those parts might not have been the best for the design, particularly at the time, but we have to remember that there is a wide variation, around 50% or so, between transistors with the same numbers on them.

The implication of a specially complementary series of parts puts us in a subjective can of worms where we have to listen to all permutations of the available parts on our bench. I just can't accept that as good design.

Looking at the schematic, I think it's topology deserves more respect than "only a guy with especially good ears can build it, not you."

[Steve Eddy]

Originally posted by Nelson Pass
Looking at the schematic, I think it's topology deserves more respect than "only a guy with especially good ears can build it, not you."

Yeah, kind of silly how some things can be elevated to what amounts to cult religion complete with prophets and saviors.

Oh well. At least they're not out on the streets abducting people.

se

[P.Lacombe]

I think that because of the considerable advancement of the science, we are now able to manufacture better violins that Stradivarius ones

Pierre Lacombe.

[jean-paul]

Yeah, I kind of get the feeling it's just an attempt to maintain some sort of mystical aura about the amp and its designer.

And you know how touchy those French are about heathen Americans meddling with their cultural icons. Jerry Lewis notwithstanding.

Le Monstre was and is an exceptional amp. Jean Hiraga spent a lot of time in finding a sonical balance with the choice of the transistors. It is not about technical properties of the components, he designed with only with the soundquality in mind.
In fact he studied every used component so extensively that I think others could have designed a whole amp in the same time. Some people I know that built the amp say it only sounded good with the prescribed types and not with any substitute. Not even the same type but the wrong colour ( for example higher Hfe ). They tried to built it with other components but results were disappointing. Even the PCB had a great influence on sound. Some thought a PCB with wider traces would give better results but that didn't work out. I remember that L'Audiophile in Paris sold the semiconductor sets for DIY purposes.
This amp had a great following of people in the Netherlands as well because of its very good sound and was built by many ( mostly without the batteries though ). The S/N ratio was extreme for that time.
So the mystique around this minimalist amp is not made up. The man really devoted his time to designing beautyful but tiny amps with a sophisticated character. The 8 Watts it produces are quality 8 Watts.
So it's a question of quality and not quantity. That may be hard to swallow for some.

To qualify this amp or its designhistory just by looking at a schematic without even having heard or seen it is unfair and unrealistic. But some people just want to believe that bigger is better ...

[Steve Eddy]

Originally posted by jean-paul
Le Monstre was and is an exceptional amp. Jean Hiraga spent a lot of time in finding a sonic balance with the choice of the transistors. It is not about technical properties of the components, he designed with only with the soundquality in mind.

Except that "soundquality" is ultimately a subjective determination. What's being passed off here is the notion that Hiraga's particular subjective preferences are somehow the One True™ benchmark for "soundquality" by which all else is to be measured.

And that notion, in my opinion, is just plain absurd. And the notion that anyone who would dare consider building this amp with parts other than those specified being little more than infadels and blasphemers more absurd still.

se

[jean-paul]

What's being passed off here is the notion that Hiraga's particular subjective preferences are somehow the One True™ benchmark for "soundquality" by which all else is to be measured.

Where can I read that ? Only Nelson can qualify for that !

[Steve Eddy]

Originally posted by jean-paul
Where can I read that ?

In the posts which imply that the amp can't possibly be improved by substituting parts.

se