Mods to Primaluna Evo400 preamp

Has anyone modded their Primaluna Evo400 preamp? Or a similar preamp / integrated?

I'm looking for recommendations to tweaks. Does changing the input jacks to higher quality, or swapping capacitors help?

I am enjoying this pre, and have locked into a supply of 12AU7 tubes. I don't see changing it anytime soon. So therefore, it's time to mod!

Finally... if anyone has a circuit diagram, that would be super helpful.

kwhilden05-02-2025 8:56pm

dekay Details Discussions Posts This discussion Message User 5,747 posts 05-03-2025 at 09:46am Copy Comment URL Report Comment Edit Delete I would roll the two center 12au7 tubes before modding. DeKay
kwhilden OP Details Discussions Posts This discussion Message User 3 posts 05-03-2025 at 01:24pm Copy Comment URL Report Comment Edit Delete Yes, already doing the tube roll thing.its quite enjoyable.
grk Details Discussions Posts This discussion Message User 246 posts 05-03-2025 at 03:37pm Copy Comment URL Report Comment Edit Delete Talk to Kevin at Upscale Audio...I'm sure he would be more than happy to walk you through some mods. ; )
tablejockey Details Discussions Posts This discussion Message User 4,029 posts 05-03-2025 at 03:38pm Copy Comment URL Report Comment Edit Delete The new adjusted "tariff" price is now $6K for your PL. Yikes! May as well spend a little more for something like ARC, VAC, etc. I would enjoy it as is with NOS tubes also in the rectifier slots-pricey but you already know that. If it were an integrated amp, the coupling caps can make an audible "improvement." No way you'll get a schematic, unless you had an "inside connection" with an authorized service guy that has access to PL info. Do fancy boutique input/speaker jacks REALLY improve SQ? 🤔 Maybe with the pedigree solder and Nordost Odin cable?