Hiraga 20W class A

[triode_al]

Originally Posted by gaborbela

Hello
So you say to use the connection at the mosfet version it was correct. Connect to the ground!? Like the schematic at the post 571?
Please advise if I understand it well. All do I want to go a bit higher PS voltage. About 17V rail voltage but I still do not think that extra 5V will do 5V swing.
Greetings Gabor

Yes, post 571 is correct for this input pair.
But just a tip that with higher power you also use a higher feedback divider (like Hiraga goes to 330 ohm/10 ohms in the 30 W version of Le Classe A).

The interesting part is that in this topology the output FET will have a different punch than in the F5 . . . and will definitely have a lower shoot-over. Good for e.g. electrostats or other complex drivers. (F5 exhibits overshoot at very high frequencies).

That explains my interest.

[gaborbela]

Thank you
Honestly I didn't heard big difference at the Class A with higher resistor on feedback or capacitor on feedback.
Actually I do not like capacitor on feedback on the feedback resistor very much. It get a bit muddy the sound..
If you exchange the 5 or 10W resistor for 0.33 that you can hear it right away. More dynamic, bass etc but the power transistors will get more load-- more heat.
To return to the LeMonstre I like these version. I want to test it.
I purchased the semis but one side they sent me not N type. Huge difference between the N type and with out.
I have to get the right mosfet. Also I prefer the red resistors from Parts Connexion.
I tried before Dale (not bad) Takman (not my cup of tea) but the PRP well balanced resistor (very little color or nothing).. I want to use that.
I never built the F5 but I built the Profet and not bad amp.
One think when we build a simple amp like these very sensitive to the parts what we use done to the wire to.
Thank you
Greetings Gabor

[Rixsta]

Hi all
This is my amp here, Fake +/- 21v



Amp board, so my question those two variable resistors, what do you think one is dc-offset ? and the other Bias ? but i don't know which one is which.

[Rixsta]

i ask this as the original does not have 2 potentiometers in....

[zeonrider]

Originally Posted by Rixsta

Hi all



Amp board, so my question those two variable resistors, what do you think one is dc-offset ? and the other Bias ? but i don't know which one is which.

Closer for input for DC ofset.

Regards zeoN_Rider

[Rixsta]

Thanks, i see that i have to adjust both. i presume about 0.5v will give 1amp bias. This is my first Hiraga amp, im used to Nelson Pass amps

[katip]

Hi, everybody.
I want to do this project so I'm seach for "jean's hiraga 20w class A" on Google.
I found this pcb (see the picture) Do you think it work for this project?



circuit for this pcb



With best regards
Katip