@jabDo you change your tubes out every time on sub-optimal recorded music or restrict listening only to the best recordings?
All tube amps have tone controls, they are called tubes. Different brands have their own sound, from bright to dark sounding.
@oldhvymec
I run Cary V12R at 100 wpc and EL34. They work perfect for me 60 hz and up. BUT I use them at 300hz and up.. Just a perfect valve for mids and highs...BASS not so much.. 60 hz and up will work though..
My former V12R with had gobbs of bass, way more than I needed, even comparing to my Cary SA-200-2. solid state amp; 92.5 db speakers. It’s all speaker dependent too. I loved the sound of my EL34s in the V12R.
Keep in mind, the OP has Hersey IVs, a big passive radiator on the back, super-sensitive at 99DB efficiency. Friends of mine run IVs with 10watt Triode amps, 6L6, KT77, KT88s, plenty of bass in the right room setting.
Holger’s EL34 40W/ch (Erhart-Audio) Basie amp is plenty for Hersey IVs. However I agree KT88s and higher do offer more bass drive in the right amp.