Robust and built by Audiophonics at an amazing price.
The sound is excellent. Ranked 5th out of many numerous amplifiers in the ASR ranking.
After a few days, the unit sounds even better.
Unfortunately, this amplifier requires 13-14 volts of input voltage to deliver its full power.
Most preamplifiers deliver up to 2-2.5 volts.
It is possible to adjust the gain on the bottom of the unit using the preamplifier itself.
Unfortunately, this somewhat degrades the excellent technical values (Sinad from 137 dB to 128, etc.).
These are still excellent values, and I don't hear any sonic differences on my Nuvero 140.
Audiophonics specifies the following gain values:
Bypass: 11.5 dB
19 dB
25 dB
31 dB
33 dB
The following values can be set on the device:
11.5 dB
19 dB
24 dB
28 dB
I love this amplifier. I've certainly owned over 10 select and well-tested amplifiers before.
The LPA-S600NCX is my favorite.
Plenty of stage, plenty of detail, and decent dynamics.