Can the top end of a PrimaLuna Evo integrated be tamed w/tube rolling?


This weekend I have a PrimaLuna Evo 3 as a house guest to compare with my Supernait 3 solid state integrated. Both are about the same price, basically tube vs solid state. I am a big fan of the Naim PRaT but I also find the depth and transparency of tubes very engaging. The Evo integrated on its own lacks the rhythm and pace of the Naim but it does have transparency and imaging in spades.

So the idea is maybe run an Evo 3 preamp instead along with a Naim 250 (or just use the amp section of the Supernait).

But one problem I cannot get over is that there is a very fatiguing high end to the Evo 3. Cymbals, snare drums, top edge of distorted guitars, etc are pretty harsh at any volume higher than background music. To compare, my vintage Luxman valve preamp into the SN3 does not have this quality (but it lacks the refinement of the PrimaLuna).

It would be ideal to do some tube rolling to get the best of all worlds... is there a tube selection that could work with the Evo preamp that would tame the harsher high end and smooth out the sound a little bit on top? Or is this just a part of the PrimaLuna signature?
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Thanks for all the input everyone. I have swapped out the stock driver tubes for a pair of Mullard 12AU7/ECC82 and found that it has smoothed out the top end, and also centered the balance better which tells me maybe the stock 12AU7s may have had some uneven wear on them or something. 

It is definitely sounding better after listening into the late night last night and again this morning. This morning, swapping back out with the Supernait 3 and the Evo definitely has an edge on transparent realism and engaging sound. I am using the Naim NDX2/XPS DR as the streamer/DAC so that helps quite a bit.

I'm pretty much ready to abandon the idea of trying an EVO preamp with the Supernait as I just don't think the Supernait is working well with my speakers. I have struggled with it since September and the EVO seems to be dialing in right out of the box. 

@erik_squires thanks I definitely have the room treatment covered pretty well in my room. These are some temporary 244 bass traps for corner and first reflections (took them down from my home theater) but I have new ones on order for permanent installation... unfortunately with Covid GIK is several months behind on production and shipping. My November order should arrive the first week of February (hopefully). 

https://www.smugmug.com/gallery/n-nh4Np6/i-b8N2h4n/A


On my Prologue 2, I changed out all preamp tubes to JJ high performance gold pin. Tamed the high end nicely. Has a warm, rich sound.
Strange to hear Primalunas sound harsh in high end. They actually are known, especially the Evo line, for soft, warm highs.

I've had the exact opposite experience. I wanted more upper end detail.

You haven't burned in the amp and tubes enough yet ... you can tame that high end just by playing it for a week or so ...
Don't forget the ceiling for damping/diffusion

The 2 innermost 12au7's as you have found out, are the money slot.
If you decide on PL, check out Upscales page on different 12au7's. There are user reviews particularly with PL owners experiences.

I use the Brimars in my PL HP.