Pass Labs XA-25 vs XA-30.8 amplifier

I had the same question for other speakers and there was a lot who really think the XA-25 is a very special amp. I love mine and you should read about it. The only question I have for your speakers is what the impedance curve looks like; if it needs power, then perhaps you need a more powerful amp than either of these. But the XA25 can deliver a lot of juice and it has driven every speaker I've tried with it, including some around the (basic) specs of your Audiovector.

From amp designers I know, the XA25 has some of the finesse and sweetness of the First Watt line Pass makes, but no other Pass amp does this (except in the SIT series).

Here’s something relevant:

"Based on actual comparisons, it’s thus fair to say that the XA25 packs virtual Nagra-type small-bottle sonics in the areas of tonal bloom and the ability to track recorded decays. If now we return to Nelson Pass’s 2017 design notes, these results would seem less due to the ‘single-ended’ use of his unusually potent Ixys output devices but what their use eliminated – typical degenerative feedback. It’s how the XA25 differs from our XA-30.8; and apparently how it manages to eclipse it on subjective speed and suchness without sacrificing the usual markers of class A Pass tuning. We’re told that scaling up this recipe to power ratings well beyond the XA25 won’t be easy. In fact, I don’t think it’s happened yet. In that regard, buyers pursuing the smallest amp in the current Pass Labs catalogue actually get something the bigger ones don’t have. It’s bragging rights of a different sort. Here it’s not the guy with the heaviest costliest amp who wins but she who bought smarter speakers which don’t require excess power so can exploit a smaller more sophisticated or purist gain circuit to drive them. In case you’re still reading between the lines: had I discovered the XA25 before I purchased the XA-30.8 as my resident class A example, I’d have saved myself both money and handling fits. I like the sound of the smaller amp even better; and my back much prefers it, too."

https://darko.audio/2023/02/pass-labs-xa25-review/

Also: https://www.stereophile.com/content/pass-laboratories-xa25-power-amplifier-page-2

Additional comments about my Pass XA-25:

The bass is not woolly or fuzzy. Across speakers from 87db to 97 db sensitivity.

The amp is not clinical.

The amp sounds different with a tube preamp vs. a solid state preamp in front of it, but it never lacks the musical warmth that @audphile mentions. With his 30.8.

The amp's name belies it's power. It has a lot of "grunt" / horsepower.

@curiousjim I bet they'd be fine for those speakers. A lot depends on the impedance curve but I used the Pass XA25 for speakers with very reasonable impedance curves at 87 and 91 db sensitivity and the amp never faltered. 

https://www.audioholics.com/loudspeaker-design/loudspeaker-sensitivity

Basically (in case you don't know): 

An audio speaker's impedance curve shows its electrical resistance across frequencies, indicating how easily an amplifier can drive it. Curve dips to low ohmic values (e.g., 2-4 ohms) demand more current from the amplifier, making it a harder load. A large phase angle (deviation from 0 degrees) at certain frequencies further stresses the amplifier by forcing it to deliver voltage and current out of sync. Speakers with significant dips and phase shifts are tougher loads, requiring more robust amplifiers.

The XA25 is designed to deliver significant current, with a peak current output of 10 amps, which translates to a 200-watt peak into a 2-ohm load. It also has, if I recall correctly, a damping factor of 500 and this gives it excellent control over the speaker's drivers, especially the bass passages.