ModWright Oppo 105D Tubes To Chill Out 2kHz-8kHz

how did you hone in on 2-8 khz?

i have only two trusted sources for tested tubes..

Andy at Vintage Tube for non Russian

Roger at RAM for everything...

probably two of the most knowledgeable and reputable testers, backers and sellers. Roger in particular ascomputerized his proprietary test parameters...consults to tube manufacturers, builds his own line of tue gear ( music reference )......

just looked over this rather extensive mod...wow..cool. What does Dan recommend ????
my guess is might benefit from dampers ( i like ARC ), and seperate HRS bases for each box, likely a damper block on the 105.... and certainly experimenting with a dedicated circuit /  condtioning....

i would start w output, work backwards....

have fun...

but in the meantime, I will be listening to the second harmonic of key # 87...

almost right at 8k

Sell it.   There is no other way.

You’re talking in the range of vocals? How does anyone even know where to start on this one? Could be a million reasons outside of your 105D or the tubes. First thought is room treatment, placement of your speakers and listening seat. When you slap your hands do you get a ping or is your room already fairly dead?  Any other of your components or speakers could be bright and not the 105D. Not sure I’d jump to selling your 105D though.

As mentioned earlier tube dampers are an option that might help. I like the Herbies best but they take some effort on where you place them. 

I’d start with your room and speaker placement. Look up how Wilson Audio sets up their speakers in a room, on how they voice the room by using your own voice standing with your back to the wall and slowing walking out into the room until your voice sounds natural. Too close to the wall and your voice will sound chesty and too far out it gets thin. Should be able to find a better description of what I’m referring to but that’s basically it.

How many hours are on your tubes?