Threshold?

these are classic amps, and they produce a huge soundstage. they are arguably more neutral than the pass and forte. the forte is a bit more forgiving on poor recordings but in most ways(open highs and midrange..bass control..pinpoint imaging)all the older thresholds are fantastic.

Jrd351 nails it. Here's some anecdotal evidence from my Threshold journey:

In the early 90's I phoned Threshold to ask them which new Forte power amp they'd recommend. To my surprise, Threshold suggested a used Threshold S/300. My contact deadpanned, "you should be able to find one, they were quite popular." Sure enough, shortly thereafter a S/300 Series II appeared in the local paper and I got it. Paired with a Forte F44 preamp, the bass was just a tad slurred. At top volumes, high pitched intruments like soprano sax, flute, upper register piano and violin sometimes sounded screechy. Trying to solve these problems, I replaced the large can caps in the S/300 with equivalent new OEM Mallorys. The sound became a little smoother but it didn't help with the distortion at extreme levels. Then I switched to a Threshold Fet ten/hl preamp and all the problems vanished.

Search everywhere you can, get a handle on the different iterations and you'll figure out which model is right for you.

Is a very nice amp, still have it, and I have tubes, I go back and forth, the tube amps have been traded for different tube amps, and I futz with caps, and roll tubes, and then change the amp.

The T Hold remains.

Is this one of the 'Stasis' amps? This technology has been almost universally rejected by all the companies which once employed it. I know Threshold used this design for a while.

Nelson Pass has gone in a completely different design direction over the last several years.

BUT there are still many people who still like the design, FWIW.