Glad to hear others have had success using a multiplier.
I'm certainly willing to add more buffer capacitance to the output of the supply if I feel it needs it after listening.
from what i remember, the goal with Le Monstre was to design a solid state amp that would get close to a single ended 2A3 tube amp
at the time 2A3 was hot, and almost a mystery tube
clearly 'early days' for the revival of tube amps...so to speak
I guess the 8watt Le Monstre would look different if designed today
at the time 2A3 was hot, and almost a mystery tube
clearly 'early days' for the revival of tube amps...so to speak
I guess the 8watt Le Monstre would look different if designed today
improved Hiraga based on le monster
Hi all,
As promised I like to inform you with my project the improved Hiraga based on le monster
I am using MJ802/MJ4502 out put transistors
Idle current is 1.5 amp dc, Vdc 30 v each rail
After long run in idle mode and readjusting the Vout offset,
Connected to my system, Acoustat 3 spk and Odyssey solid state pre amp
YBA is my cd source
Well how it sounds like? Very well and a lot of details comparable to my pwr amp
It is built like a proto type with a huge pwr supply and big heat sinks
Now I have finished building the super Hiraga and working on increasing out put pwr
So wish me luck!
I attached some pics
Best regards
Williams
Hi all,
As promised I like to inform you with my project the improved Hiraga based on le monster
I am using MJ802/MJ4502 out put transistors
Idle current is 1.5 amp dc, Vdc 30 v each rail
After long run in idle mode and readjusting the Vout offset,
Connected to my system, Acoustat 3 spk and Odyssey solid state pre amp
YBA is my cd source
Well how it sounds like? Very well and a lot of details comparable to my pwr amp
It is built like a proto type with a huge pwr supply and big heat sinks
Now I have finished building the super Hiraga and working on increasing out put pwr
So wish me luck!
I attached some pics
Best regards
Williams
A quick question about the alpeh M 10 watt boards. Do they have to be driven balanced?
Pass ALEPH-M DIY Class-A amplifier PCB
Pass ALEPH-M DIY Class-A amplifier PCB
Did someone ever tried to reduce the Emitter resistor.
I think the 1R a bit to high.
When the amplifier was developed the main goal was to drive tweeters with.
So many people who built the amp among me to wrote the Le Monstre luck the deep-deep bass.
Probably It has to do something with that high 1R emitter resistor.
I have some experience when I increased the emitter resistor that somehow cut into the dynamic and bass with other amplifiers.
May be if we reduce the emitter resistor from 1R to 0R33 or so the amplifier will be unstable or the power transistors will get very high current.
I think these need to be done (at least tested) step by step, from 1R slowly reduce the value..
I built several Le Monstre but I never tested these, to build one now just to test it that would be a waste of time, energy and money.
Any idea opinion about these taught welcome.
Greetings Gabor
I think the 1R a bit to high.
When the amplifier was developed the main goal was to drive tweeters with.
So many people who built the amp among me to wrote the Le Monstre luck the deep-deep bass.
Probably It has to do something with that high 1R emitter resistor.
I have some experience when I increased the emitter resistor that somehow cut into the dynamic and bass with other amplifiers.
May be if we reduce the emitter resistor from 1R to 0R33 or so the amplifier will be unstable or the power transistors will get very high current.
I think these need to be done (at least tested) step by step, from 1R slowly reduce the value..
I built several Le Monstre but I never tested these, to build one now just to test it that would be a waste of time, energy and money.
Any idea opinion about these taught welcome.
Greetings Gabor
IMHO le monstre are more sensitive to the speaker type. Its measures well with Full range, but with 2way speakers you have dips and peaks in response (attached LT sims, but in real life its almost the same - i measured once with sound card on real speakers). You can bypass source resistors with caps -
See attached pictures. 1st - no caps, 2nd - with 100uf bypass
See attached pictures. 1st - no caps, 2nd - with 100uf bypass
Attachments
Of course it is sensitive, because it has a high output impedance. Every crossover will show up in the chart.
What can be done is have balancing filter sections to smooth the impedance.
All this is the same for tube amplifiers.
However some find that with high sensitive speakers the extra sections also 'suck' some livelihood.
- But I like your idea !
I don't think, that using Toshiba 2sc2235+2sa965 as drivers is good idea. Maybe Sanyo 2sc3468+2sa1371 (3467+1370) will be better (but I'm not sure). In the theory as driver you can to use Motorola BC550C+BC560C with small radiators (I'm not sure too).
p.s.: sorry for my english
smps le monstre
Here is a first amplifier build of my le monster on the cheap (I am a beginner in building amps so don't be too hard on me):
I had two RS switch mode power supplies (+/-12V, 1.8A) lying around and had found not too expensive preassembled old version boards from diy-audio-world on eBay. The boards use some changed components (power resistors e.g. would be better if non-inductive) and use K246_GR2k / L4f transistors and tip3055 / tip2955 output transistors. The case from modushop was expensive but is nice and has room for a second channel if I add a tweeter to my frugal horn speaker, or decide to upgrade to amore powerful pass f5 build.
The sound of the smps le monster is pretty good, comparing it to a miniwatt 2.5Watt single ended tube amp, I am happy, my le monster might have slightly more attack in the highs. There is slight hum in the high sensitivity foster drivers, but not too bad, and I think I can improve shielding from the sips (funny thing is that hum is reduced when touching the shield of cinch input). However I have slight problems adjusting the dc offset for one channel, as it fluctuates and is super sensitive on the potentiometer setting. This channel also is slightly louder. Both power supplies deliver stable +/-12.2V and the bias current is a perfectly stable 0.6A for each transistor.
Does anyone have tips how to reduce the amplification of the louder channel and why the balancing in this channel might be trickier?
Thanks, Stefan
Here is a first amplifier build of my le monster on the cheap (I am a beginner in building amps so don't be too hard on me):
I had two RS switch mode power supplies (+/-12V, 1.8A) lying around and had found not too expensive preassembled old version boards from diy-audio-world on eBay. The boards use some changed components (power resistors e.g. would be better if non-inductive) and use K246_GR2k / L4f transistors and tip3055 / tip2955 output transistors. The case from modushop was expensive but is nice and has room for a second channel if I add a tweeter to my frugal horn speaker, or decide to upgrade to amore powerful pass f5 build.
The sound of the smps le monster is pretty good, comparing it to a miniwatt 2.5Watt single ended tube amp, I am happy, my le monster might have slightly more attack in the highs. There is slight hum in the high sensitivity foster drivers, but not too bad, and I think I can improve shielding from the sips (funny thing is that hum is reduced when touching the shield of cinch input). However I have slight problems adjusting the dc offset for one channel, as it fluctuates and is super sensitive on the potentiometer setting. This channel also is slightly louder. Both power supplies deliver stable +/-12.2V and the bias current is a perfectly stable 0.6A for each transistor.
Does anyone have tips how to reduce the amplification of the louder channel and why the balancing in this channel might be trickier?
Thanks, Stefan
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