Help me in choosing fets

[pamaz]

Dear All,
I know this has been discussed several times, but still I can't clear out my mind.
Therefore, being on the run for building 2 aleph 30 ( biamped system) I would like to know if IRF044 ( easy to find here in my area) will be a good/proper choice in aleph 30, and if it's possible, the reasons for this.
I know that the 50V rail to rail of A 30 are close to the 60 V limits of the044, but usually the datas on semis are conservative.
Any help will be really welcome

In the meantime thanks to mr. Pass and Mr Colburn for sharing the ONO circuitry (that I've completed). Just for this Machine I've some difficulties in listening to cds!!

Thanks and bye.


Paolo

[stefanobilliani]

Hello Paolo,

The Aleph 30 rails are +and- 25Volts;
Reading the ZenV4 pdf I find out that a 044 should not dissipate preferably more than 50 W .
So ... each fet on an A30 is at 0.5A of bias current , and it will dissipate 12.5W.
Thats is pretty good for the IRFP044, well under its limits.

[pamaz]

Hi Stefano.
Thanks for your reply. I agree with you and I made roughly the same evaluation, but this question is a just a confirmation of my thoughts.
My doubts were if any other problem could raise for other particular characteristics of the 044.
You know, this is a nice place just because you can check things with other experienced people, before making attempts ending with smoke.. fire....explosions .
Ciao Stefano e Grazie

PS. Credo in settembre di essere dalle tue parti, e mi piacerebbe conoscerti, ma ho perso tutti i tuoi riferimenti a causa di un format c: che sono stato costretto a fare.
Se ti va ancora, mandami una mail.

Grazie

[Dennis Hui]

Hi Paolo,

I used IRFP044's in my A30 and have been listening to
it for almost one year now. Hot heasinks, but no
explosions yet.

Cheers,
Dennis

[pamaz]

One more confirmation that makes me happy.

Thanks and bye Dennis.

Paolo