Hi Pann56.
Some time ago I've ordered a pair of NOS Toshiba EL84/6BQ5 and the sound was completely muffled and the output was down by 50%.
I've put back my Electro Harmonic EL-84 and never changed them again.
I thought I was doing a good thing buying some NOS tubes.
It's not always the case.
My EH EL84 are very details therefore perfect for my Omega 7F Open Baffle Dipole speakers.
Hope this help or at least does not make you more confused.

Guy 13 on planet Vietnam.