You may consider reaching out to this guy http://stritt-audio.de/

Strawman. I didn't say there is no difference, did I?

Well, there isn't, quantively speaking.

Thank you for sharing your experience, Kevin, I appreciate that a lot! I'll certainly look into dale resistors instead of whatever I'm currently using.

Thanks Kevin, too bad I don't have a scope with said capabilites. Do you think the suggestion would be beneficial? Could osscilation harm the 10M90S permanently? People were having problems like mine earlier, as stated e.g. here https://www.audioasylum.com/cgi/vt.mpl?f=tubediy&m=252144&VT=T

Found this link https://db.audioasylum.com/mhtml/m.html?forum=kandk&n=9229&highlight=oscillation&search_url=/cgi/search.mpl?forum=kandk Could that help? Apparently, finding 10M90S is very hard these days...

Any other idea what to look into? I don't know what else to try... Do you guys think it's reasonable to buy some new 10M90S (originating from another lot, hopefully) and give them a try?

Yeah, I thought so too, thanks for the confirmation. I'm indeed using these white ceramic insulators and thermal grease as you did. And bushings to insulate the screw from the fet, of course. Exceeding the Vgs limits could harm a fet and limit its capabilities. Could that may be the cause...

Hi Jim, thank you for chiming in. For the 007t I'm using a pair of heatsinks like the SK 92/50 AL from fischer elektronik (if I recall correctly). Each is about 100x40x50mm @ 1.9°C/W. Each heatsink has two insulated 10M90S on it. Should be something like 5,6W per heatsink, right...

I've been using the TO-92 version exclusively. Haven't had any issues with that in my former SRM-006t so far.

First of, I'd like to thank all the folks participating in this awesome community from all the different countries, JimL, Spritzer, Kevin Gilmore, Sören, Firschi, you name them. While being very new to head-fi, I'm not entirely new to tinkering with STAX devices. Back in late 2020 I replaced...