First Watt Amps - Nelson Pass

[Chris A]

...That being said, got sick of maintainance on my tube gear and always needing to bias the amps and having the tubes age at different speeds, and they do.

What can I say, other than "I agree". Personally, I don't like amps that have their own sound - I'd rather have accurate reproduction than "pleasing", with low intermodulation distortion. Amps having their own sound (...usually in the form of lower-order harmonic distortion...) usually sound lousy when they try to reproduce string orchestras, which is a big deal-breaker for me. SS amps using moderate amounts of feedback usually have lots of higher-order harmonic and modulation distortion which makes them sound "thin" and clinical, IMHO. See the Nelson Pass article on the subject of "Audio Distortion and Feedback" for a much better explanation. See particularly his discussion on "the elephant on the dance floor".

...Bought a First Watt F5 to compare to my quasi-triode marantz's and what a difference...What I came to realize is that the marantzes were just colorful and the F5s were not, if they do have a sonic fault it is they're lean maybe, not thin, but not quite meaty enough perhaps. Now I had highs and lows with great attack and good decay...the quickness of the F5 is amazing when compared to the Marantzs, not even the same league - quick as greased lightening as they use to say.

Interesting observations. Note that the F3 is supposed to be more "tube like". There were only 100 of the F5s made, IIRC, so they're out of production now, and very difficult to find preowned.

The next big thing I was not really aware of is the noise floor of an amp, that threshold where the amp at idle is generating hiss or noise and how low or soft it is in relation to the music. Horns might actually make this effect worse..

Probably much worse, in fact. My K-402/TAD 4002s have a sensitivty of 110 dB/W/m, which is probably at least twice at loud (psychoacoustically) as most other "high efficiency" speakers. Also note the issues with reverberation effect due to the efficiency of the speakers turning themselves into microphones used with high-output-impedance amplifiers.

This is a key component, in my opinion, for low level detailing and the ability to listen at lower, ear saving, volumes/late night too. The F5 was just a revelation, I heard stuff in my records and music files that I never knew existed, example would be the sound of a snare brush being slid across the drum head, a very soft "swish" that somehow appeared from nowhere on an Alison Krauss album. Little stuff the artist or producer purposely put in there that none of us get to hear unless you're using high efficiency speakers and amps with a very low noise floor.

Another interesting observation.

Chris