Le Monstre it has an amplification of about 26dB (x20) while the M2 only has 14dB (x5), so that's why you hear the noise of the preamp that you didn't hear before. Reduce the 220k resistor below 47k and try again.I've been experimenting with various resistor values on the Le Monstre inputs. I'm now at 3K series and 220K shunt., I think this is about as far as is sensible.
The hiss from my DHT pre is greatly reduced, but it's still there.
This pre is silent into an M2/ LuDEF. What's going on here that I've missed? Is it just the case that the pre has too much gain for the power amp?
Thanks
For Le Monstre, about 1.3Vp-p is enough for full power, so it doesn't need a preamp with a good source.
I drive mine only with my DAC, which has an output voltage of 8.64Vp-p or 3.02Vrms only through a passive of P&G 10klog slide pot .
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They have been out of production for 20-30 years, so if you get some, they are probably fake...I have only the one question: Where are you getting 2SK170Y+2SJ74Y (key word "Y"
Hello,
Surely
The French company selling them surely was not big enough to get them closely matched.
Most of the time most of the Japanese parts they were selling were out of stock.
Greetings Eduard
Anybody who has built this Hiraga 30W using prasi's pcb?
What transistors are you using?
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I have a Super 30w but with the PCBs and all the original parts (the audiophile's house), I can't help you with the Prasi boards.
on the other hand, I can tell you that it is an excellent amp, very sensitive to its power supply.
I had made a first assembly with a simple power supply before receiving my order of 6 x100000uF, the amp was very different afterwards.
It's been with a friend for 15 years and we even use it to have dance parties with Cabasse Sampans lourd.
on the other hand, I can tell you that it is an excellent amp, very sensitive to its power supply.
I had made a first assembly with a simple power supply before receiving my order of 6 x100000uF, the amp was very different afterwards.
It's been with a friend for 15 years and we even use it to have dance parties with Cabasse Sampans lourd.
Almost the same with 2uF 160V in parallel with the last two and 26 Vdc.±24VDC, Bias 1.5A, 1.456F (68000uF->0.22 ohm 25W->0.66F per rail).
No soft start, and just DC protection at the output (Velleman)
I check it every 4 or 5 years (during the aperitif) and it has never moved.
Hello,What?..
Jean Hiraga wrote about le monstre when it first appeared in Japan being a small power amp with a big power supply.
In the famous French magazine appeared some articles about pimping the power supply. It was the general idea back then if you dont need a lot of power le monstre works very well. A bigger/ better power supply would make it sound more powerful.
The 20 and 30 watt were designed by Hiraga ( maybe based upon another design, i forget) . At least he and his " crew " in France spend loads of time making it better or making changes when certain parts ( drivers and output transistors disappeared from the market )
Since then there have been people who think they could do the same using a similar topology, other resistors, transistors, potentiometer, power supply caps turning it into an amp which is not an Hiraga anymore.
Greetings,Eduard