Hiss at addition in system LAMM L2


Hiss (noise) from speakers at addition in system LAMM L2.

Three weeks ago, I have bought preliminary amplifier L2 reference
Improvement in sounding all system was huge!!!! The overall dynamics and scale of the music!!!
Illusion of a presence(finding) in a concert hall has appeared.

But I am disturbed with the following:
At addition in system L2 strong enough noise (hiss) has appeared from
speakers. At inclusion of toggle-switch MUTE hissing disappears, at deenergizing
Toggle-switch MUTE all room is filled with noise (hiss).
Even at listening music on silent passes or piano music
Such noise level it is normal or L2 demands repair?
anton9005
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Rgd and Tvad, I agree with your assessment of the Lamm LL2 preamp. Especially at its resale price it is a screaming steal and a wonderful musical preamp that flat-out danced with my ML 2.1s. I found the musically to hiss trade-off to be extremely positive...and the hiss to be sort of a small attention getter setting the stage for what was to come.
It was and I still maintain that the L2Ref is a wonderful preamp that did not work out for me. It was my first foray into a big ticket expense (at least according to my level of disposable income) that left me gun shy on making further commitments at such an expense level. I have found that an ARC LS-26 (acquired at a really great price) has fit the bill nicely. My aural memory, like many people, is short so I cannot say what differences there are between these 2 preamps as there were months between them being in my possession but the LS-26 has been a solid performer from day 1 and is not on my list of components to upgrade.