IRF, IRFP or IRFZ devices?

[tmblack]

Which lineup is best for the Aleph amplifiers?
I see IRF244 and IRFP244 used in the Aleph 3 and 2 respectively.

I have a bunch of IRF530 and IRF9530, would these be good for audio?
IRFZ40 is particularly inexpensive.

Thanks

Tom

[Lars Clausen]

I guess you can use any of these devices. But keep in mind the output devices in an Aleph amplifier much dissipate a lot of power in order to operate. So you must ensure the device can transfer the waste power to the heatsink.

IRFP244 have a bigger surface to the heatsink compared ti IRFZ and IRF530. About 1.66 times bigger. So this means waste heat can be transferred easier to the heat sink. That is why IRFP244 is better in the Aleph amplifiers.

But you can counter the smaller heat transfer area by mounting the output directly on a a clean black anodized surface with insulating washer only on the screw. And of course heat compound. This will give a very good heat transfer between device and heat sink, but be sure to measure for any unwanted electrical contact.

[tmblack]

I wonder why there are 3 distinct series and how they differ in sound and distortion.

Tom

[bezobraznia]

I wondering too, Tom
Someone say difference between these transistors? And maybe exchange with similar param. but more good sounding?
Best Reggards!