Primaluna EVO 400 Amps/Preamp lacking bass impact

I have used the XLR outs to the amplifiers and SE outs to subwoofers with no problem.

The only tubes I’ve enjoyed bass from are KT88 and KT120. I owned and sold a Prima Luna integrated because of this lack. Oth the PassLabs XA25 had vice like grip on my PMC Twenty26 speakers at the time.

The amp damping factor could be a significant source of this lack of bass definition.

From a Hi-Fi World review of the EVO 400:

"Output impedance measured 
2.3Ω, giving a damping factor of 3.4 in 
Ultralinear mode. Surprisingly, figures 
were a tad better in Triode mode at 2Ω
and 3.8. Both are ‘poorer’ figures than 
that of transistor amplifiers, but really this 
is dependent upon loudspeaker acoustic 
damping. "

This low damping factor would result in less control of the speakers at low frequencies compared to an amp with a higher damping factor. The NAD M23, for example, has a damping factor >800.

I have no skin in the game to respond to this ask. I would however like to give major props to @jimmy2615 for offering such a thoughtful reply. There are really some wonderful folks helping each other out. I’ve always been interested in the Primaluna gear and love the way it sounds in my friends listening room and that’s the reason I dropped into this thread. I have Focal’s in my main room and really enjoy them. I hope the OP can sort out what he’s looking for. Good luck and cheers.

Thank you Rick.  I appreciate most when people can offer comparisons of different gear they’ve tried, otherwise you have to try it for yourself or you’ll never know.  That’s one thing (of many) that’s sad about the demise of the B&M stores …. A good dealer should be able to tell you what works with what.  Good reviewers also - for example, I appreciate when someone like Herb from Stereophile reviews an amplifier.  He’ll report on how it sounds with each speaker he has.