[SSassen]

Mike,

I'm actually using that same MOSFET, although IR only provides a model for the d-pak equivalent: the IRFR24N15D, it is however identical to the to-220 IRFB23N15D, you can grab the model off of the IR website.

Before you're able to use the IR model you'll also need to install the 'schaltplansymbole' from the download directory and use the nmos-model and use a spice directive to point to the .spi file for the IRFR24N15D.

Schaltplansymbole
http://include.php?path=content/content....&themeid=0

Also, I looked at your schematic and noticed you inserted the capacitor and resistor in a different location than me, although the result is about the same. Furthermore I'd opt to keep if fully differential, like my schematic, because then you'll cancel the 2nd and 3rd harmonic, and hence reduce THD. In my case I've not been able to get THD >0.05% yet, but there's some progress still.

Cheers,

Sander.

Edit: typos