Hiss at addition in system LAMM L2

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.

I had BAT Rex in my system recently, paired with BAT 75-SE, and it was "dead silent"- I could only hear very low level ground loop- type cycling humm with my ear literally 1" from the tweeter, which I'm positive, was related to my power lines, rather then Pre/Amp themselves.
So, I guess hiss is a byproduct of less, then perfect design, and not inherent to tubes or mosfets for that matter.

Considering the bad user experiences and opinions being
expressed, I suppose there'll be a glut of used L2 Reference preamps in the
listings soon. Mine won't be one of them, however.

It might be helpful to know the sensitivity of everyone's speakers who are
experiencing excessive hiss with the L2 Reference. Mine are 93dB, and as I've
already written, the hiss is normal, IMO, and certainly within the range of hiss
I've heard in my system in several iterations with other gear and speakers
(89dB).

I have had a few iterations where there was zero hiss...and I mean none. The
amps were NuForce, Bel Canto, and Leben. Preamp was Atma-Sphere.
However, none of the systems were as musically satisfying as the one I have
presently.