Pass amps can they handle a highly reactive speaker load?


Ok so I've learned a lesson after being in this hobble for almost 40 yrs no matter how great a tube amp is it will only be as great as it can be on a speaker that doesn't dance around with its impedance load electrically. How well does pass labs amps handle this situation? Martin Logan's are a very reactive load would pass handle the job.
speakers M L 15A.
hiendmmoe
It depends on the Pass Labs model. Some of the Pass Labs Aleph models were unsuitable for such a load. Other Aleph models might be good. Most of the X series should be good.  I too am a fan of a lot of Nelson Pass's work, and it's a become a tad controversial to criticize his work around here lately, but I've found some of Stereophile's bench testing measurements a bit concerning. Despite general assumptions about the technical capabilities of these amps to the contrary; it appears as though more than a couple of Pass Labs products have struggled on the test bench when driven into some lower impedances. Could be a good or even excellent choice, but tread with some caution.
Ask Pass himself. Go to Pass labs and email him. Last I heard he still answers his own email. 


I'm building a First Watt F5 and I've been pouring over diagrams and forums on his amps as much as possible. Pass amps, in general, use simple circuits and as little feedback as possible. Some will drive a 2 ohm load rather faithfully. Others will fall flat on their face. Pass branded amps generally drive Focals nicely and their speakers tend to have some trying low points. Pass tries to get decent specs on his amps, but hell deal with a weaker damping factor, .01% distortion, or nonlinearity if it makes it sound better. 
It depends on the Pass amp. Audiogoner whitecamaross has been on an epic journey trying different amps, including many with ML 15As. Here is a quote from this thread:
My Long List of Amplifiers and My Personal Review of Each!
"Pass and Logans are an unbeatable match though. "

The quote is from the end of page 6 of the thread. It’s at the end of the post dated 06-04-17 9:21am. I’m sure he’d be happy to discuss it with you.


My Pass XA 60.8's drive the load of my fairly ruthless Magico S3's without blinking. These speakers have been shown to dip into the sub 1ohm range at the top of the audio band much like some panel speakers.

So far, the Pass XA's are the only amps to play well with these guys that I have tried to date.

I think the .8's would be the ones to try if you do. The added current and voltage they put out will pay dividends, I feel, in this case.