Sonic atributes ultralinear vs tetrode vs pentode


What are the sonic attributes of and amp running in Ultralinear vs tetrode vs Pentode. Looking to get a new amp, but live in a rural area can't audition them all. I don't like what I have heard from Ultralinear amps, too hard sounding for me. A lot of new pentode amps on the market, can't audition any. Why pick one over the other?
Thanks
Mike
128x128brm1
The document also has comments about OTLs that I don't agree with, as it comes from the 1950s. But the UL stuff it has in it, while obviously biased (if you will pardon the pun) is representative of the general technical/engineering understanding of ultralinear operation- its easy enough to find plenty more articles like this one. I just clicked on one of the higher-page hits on Google. I can find some of the stuff on the UL curves and that bow I mentioned if you are interested.

Full credit and abundant praise must be given to the persistent courage of the Japanese in regard to the triode tube amplification renaissance. Many of us, AtmaSphere included, reap the benefits.

For the most part the Japanese seemed to justify our stance on triodes, which we have used since the late 1970s. Back then, people thought triodes were 'quaint' (I suppose many still do). These days they have a lot more acceptance.
Trelja, IMO white papers written by companies and/or individuals with a financial interest in the content should be dismissed as marketing and sales tools.

You see a lot of that here on Audiogon.
Bak to the ops q. Mike / brm1

Try any conrad johnson tube amplifier. Almost all of them are ultralinear amps and nobody could ever call them hard sounding.

Smooth with musical detail

Cheers