The best passive preamp

Here's another vote for the NOH. With the right amps in my system it has outperformed a SimAudio P5, an Audion Premier and a Canary 801. It has clarity, dynamics, low-level listenability - there's just less getting in the way of the music.

I don't know if it will run with the REALLY big dogs - the CJs, ARCs, VTLs, CATs and Lamms of the world, but I can't see anyone being disappointed if the rest of their system is sympathetic - especially when the price difference stays in your pocket.

Anything with real transformers, as opposed to autoformers, should work. The TX102 trannies in the Bent have an input impedance of 10K to 250M ohms. They should have very little problem with any real-world source impedance. This is in marked contrast to resistor or autoformer passives, as is the very low output impedance, which is in the single-digit range over much of its travel.

I have found no constraints to the use of my Bent other than power amp gain. A pair of amps with low input sensitivity (~2v+) didn't have the dynamics when driven by the Bent that they did with active preamps. Amps with more normal sensitivity (1.5v or less) sound better with the transformers than with any of the actives I've tried so far.

I'd say to keep looking for a passive with transformers, either the S&B or Sowter.