Hiss at addition in system LAMM L2

Hiss can be annoying, no doubt.

I will add that using different power conditioners and cords has affected the
L2's level of hiss in my system. It seems to be fairly sensitive to power cords
and power conditioning, IMO. You don't necessarily have to spend a fortune,
either. I'm presently burning in an Alan Maher Reference Power Center V2
that retails for $750 including a captive power cord. The hiss level is the
same, or slightly less, than when I was using a Shunyata Hydra 2.

In my system, the L2 is better (more transparent, alive, and lacking
coloration) than the ARC Ref3, despite the ARC being nearly dead quiet.
However, this is likely due to better impedance matching with my amplifiers
than anything else.

The only other balanced preamplifier I'm aware of that has an output
impedance somewhat close to the L2 is the Modwright LS36.5. I'd like to hear
one in my system since Modwright products are famously quiet, but the
price including the PS36.5 power supply puts it out of my comfort zone.

forgot to add that I threw mine on a BPT balanced conditioner and also ran it on its own dedicated 20A line - still had the problem. Got an email from a gent in Europe after I posted my findings and his L2 Ref had a similar problem. I would imagine what could be this preamp's "best" match is a Lamm amp(s) but that was not in the cards for me...

The L2 Reference is an outstanding match with Pass Labs XA-.5 series.

IMO.

The pre will hiss no matter what you do. The hiss comes from the mosfets in the circuit and higher gain amps on more sensitive speakers will hiss more than others.
You either live with it or sell it. For me, I chose to go a lower gain amp and it remedied the problem well enough for me.

Interesting about the mosfets.

I owned a Moscode 401HR amp that used mosfets. It's a high gain amp, and I can't say I heard any appreciable hiss.

Not arguing your point. Just making an observation.