Mosfet mix on Aleph

[Ligado]

I have problem to obtain all irfp240 so I think if is possible put another type in the current source (i.e. irfp250). I have read on others threads that problem is input capacitance. This affect current source on Aleph?

 

[hifi]

They have double the capacitance i have once asked NP himself in an older thread they would certainly work but he did not know how the would sound...better? worse? ..the same?...just test them

;-)

/micke

 

[Nelson Pass]

The 250's behave a lot like two 240's in parallel. They
work, and experience says that the bottom end improves,
but the top end gets a little darker. Not necessarily
objectionable. In my opinion it improves an Aleph 3 slightly,
does not work well in a 1.2.

 

[hifi]

okie... im sorry to have miss qouted you but i believe that you said you hadnt tested it...well it was quite a long time ago..


The 250 has a much higher capacitanc i guess that is what makes the sound darker and it not suitable for the 1,2 to high a capacitance..

/micke

 

[Ligado]

Thanks all! (specially Mr. Pass)

But my question is about to use IRFP240 in the path signal (Am I wrong?) and the IRFP250 in the current source.
(English isn't my native language)

 

[Nelson Pass]

Sure, it'll work fine.

I did recently try the 250's, just to see, but I don't have
a compelling reason to go to them. I get more dissipation
capability off of 240's in parallel.

 

[Ligado]

Thank you Mr. Pass. I am finishing a copy of a kind of Aleph4. I expect you accept the pictures in your site's gallery.