HIRAGA higher power

[Williams Audio]

Hi,
The ‘hiraga classe A’ amps are relatively low power
There is some one that increased the power higher then ‘ le monstre’ 30 watts?
I was thinking of increasing the VCC to +/-50v and the voltage gain, keep the current bias around 1.5 amps getting 100 watts; the big question if it works properly.
I ran some simulations but I am not pleased with the results.
If some one can help and advise I will be grateful.
Best regards
Williams

[lineup]

You can search forum for Monstre
I do not remember if we discussed higher power here:
Hiraga "le monstre"
Hiraga "le monstre"

But sure it could be possible.
On the other hand, is often said that
One 10 Watt Class A .... can match 50-100 class ab amplifiers ... in sound quality

10 Watts RMS means +10 dB
If your speakers are SPL 90 dB/1 Watt, you will get like 100 dB level

[lineup]

You have hiraga alternative amplifier with 20 Watt:
Hiraga 20W Class A
Hiraga 20W class A

Daniel has made some great, great amplifier there.
See his latest images and posts.
For example here is one picture of his work:
http://www.diyaudio.com/forums/attac...amp=1231062965

Regards
Lineup

[danieljw]

Hi Lineup,

Thanks for the nice comments i am flattered!!!

that version i made of the 20W class A amp recently measured well.

I have actually written a little article on it for another site when it is finished i will post it it has pictures and measurements and the exact cricuit etc etc...

any how the amp ended up making about 56W rms,

if you used a larger output stage for example sanken 230 or 250W devices - (but still a single pair) and a couple of resistor/transistor changes you could get more power, however the heat would be quite difficult to get rid of !!!!


-Dan

[Williams Audio]

Hi daniel,
You built nice things. I built the Douglas Self class A amp and increased the vcc supply so, could get ~45w @ 8 ohms, but I want to build a simplier pwr amp in class A.
My spk are Acoustat 2+1 so I need some thing around 100w.
From my sim, Hiraga amp, when is switching to class AB from class A in order to deliver a higher output power is very distorted and needs to be bias at very high current in order to keep it clean, so I am wondering if can increase the output power of Hiraga amp with out distortions or degrade performance!
How did you rise up the output power?
best regards
Williams

[danieljw]

Hello Williams,

I increased the rail voltage and also the bias, you need to change a few parts also to do this,

but i think it is worth the effort

-Dan

[Williams Audio]

Hi Daniel,
looks that can be done, can you mail some more details on the
schematics and final power
best regards,
Williams

[danieljw]

Hi Williams.

attached is the orignal

[danieljw]

here is the version i am using at the moment

[Williams Audio]

Hi Daniel,
thanks alot i am testing the new scematics, next week i am starting the project. very nice you answered that fast.
have a nice weekend,
best regards,
Williams