There are so many factors involved in the overall sound of an amplifier, it's difficult to pin it down to the output tube alone. I've heard both excellent sounding 300b and 845 SETs and realized I could be happy with either if executed to a high quality standard. In very general terms the 845 is very "dynamic" yet quite organic. The 300b very "organic" yet quite dynamic as well.Some speakers will need the additional power/drive/grunt of the 845. The 300b tube has less power but is very fluid and transparent. In my case I do just fine with an 8 watt 300b and wouldn'texchange it for any other amplifier(it's ideal for my needs). The inate musical naturalness of the 300b has me hooked. Again any of these contenders can sound superb with the proper speaker match. You have a very good list of amplifiers. Good luck.
Charles,
Charles,