I have been fortunate enough to have the NHB-18NS preamp in my system for the last few days. In combination with the NHB-108 amp, using the 50 Ohm interface between the two, it is easily be the best piece of audio electronics I have ever heard. It has far exceeded my expectations which were quite high to start. It is so holographic, smooth, and "alive" that it's hard to quantify how much better it is than previous equipment I have owned or heard. The battery system has operated flawlessly so far. Can it get any better? Maybe- it’s only a few days old and there might be some additional break-in.
I think Hervé Deletraz is the best audio electronics designer in the world right now. The build quality is fanatical, the design radical, and the sound quality must be heard to be believed. It's very humbling to think your system sounds great until you put in a component like the NHB-18NS and it redefines for you what you thought was possible.
If you already have the NHB-108, don't even hesitate in ordering the preamp- it is a must have. If you own neither, order both and you will have the best amp/preamp combo on the planet. As always- this is just one audiophool’s opinion, but I'm happy as hell! Over the top actually. Thanks JT.