tubes4hifi wrote:in general . . . . triode mode is great for midrange vocals, not so good for highs and not good at all for bass.
Pentode (actually ultra-linear) mode has great bass, great treble, and very good midrange
Triode mode is something that SET (single-ended triode) fans promote, and most of them use full range single cone speakers, that don't have much bass or treble anyway.
For them, it's all about the midrange.
For me, well, that's where a great tube preamp comes in !!
Agree fully with the subjective comments above based on attentive auditions between both modes on common source material. Leaving me unsatisfied with either.
Bass too weak on triode, dissatisfied with the muted vocals on pentode. Curiously the solution to my quandary was right in front of me in the hardware I already owned, the works just needed rewiring.
Now I run my M125's 100% in triode mode w/o sacrificing either bass or treble. Bass below 80 hz is handled by a powered sub. Treble is in the hands of a 100/ch Marantz SS amp, ie took the strap off the posts on my towers so they are now biamped.
Curious the differing ways the same system can be wired and how this can fundamentally alter sonic performance. Originally I had the preamp feeding directly out to the M125's, then the M125's to the towers, no biamp. Pretty basic. However now the sub is situated between the preamp and M125's, allowing use of the subs highpass crossover filter to pass only 80 hz and above to the M125's. And the aforementioned biamping change of course assigning the treble (>10khz) to the amp on my integrated. This arrangement allows me to enjoy the wonderful midrange character of triode, but no longer at the expense of diminished upper/lower ends. Same hardware, but not the same sound! Loving it!
Would have responded sooner but as of late have been distracted by a tube related issue which I'm hoping has been put to bed, well as least for now it has