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Primaluna evo 400 - unmatched tubes

Hi
quick history....i recently borrowed a primaluna evo 100 from the local store and loved it so bought the evo 300 and immediately bought 4 matched KT150's for it, but then 2 weeks later wish i bought the evo 400 ! so my local store let me return the 300 (small restocking fee) and now i have the 400. Sounds like a lot of $$ but I'm thinking this is a lifetime purchase so have justified it that way ;-)
Because I had 4 KT150s that i bought for the evo 300 i decided to buy another 4 so i could fill the 8 tube requirement of the evo 400. I'm driving magnepan .7's so more power the better. By the way the primaluna sounds great with these speakers....I've found a low end i'd never heard even when driving with 150wpc solid state and the sound is very natural, pleasant, and unfatiguing to my ears. The KT150's in my system sound much better than the EL-34's. They sound fuller and more spacious. I sat there last night and kept wanting to play just one more song....they drew me in. The choice of tubes is related to the speaker being driven so the EL-34's may sound better on a different speaker. 
Anyhow to the issue......when i installed the 8 tubes in the amp i totally forgot they were actually 2 matched quad sets so in effect i have mixed them up. Will it matter? should i have put in a matched set per channel? Will the autobias feature negate any issues?
The 2 sets were bought from different suppliers but i don't think there would be any different markings as they were both tung-sol branded. 
mid-fi-crisis
mid-fi-crisis OP
71 posts
 
Thanks everyone. 
And especially for the quotes from the manual... They actually don't supply a manual with the amp. I guess I better download and print it.
.... Now work out a mod to enable to tube guard to go on over the massive kt-150s....
rodman99999
6,035 posts
 
Here ya go :     https://primaluna.files.wordpress.com/2019/08/1-evo-manual-integrated-amplifiers-1.pdf
tablejockey
3,804 posts
 
Find some Orings at the hardware store to fit the shaft of the cage, to allow  the necessary clearance. You probably need 2-3 for the required lift.

If you do a search, there are other ways owners done it. I use the old RCA 6L6G big bottle in my PL HP, which just fits under the cage.
oldhvymec
5,101 posts
 
I stand corrected....Thanks..

I knew someone would chime in and make sense of it all, TO ME..

I'm a little thick sometime.. actually, a lot of the time.. I'm old...

What can I say, one to many head bumps...  ;-)

Still, OLD dog new trick, do I get a treat....at LEAST!?

Regards.. 
tuberist's avatar
tuberist
951 posts
 
MidFi....congrats on your PL integrated purchase. I run a PL Dialogue Premium and use TungSol 7581A or TungSol KT120 power tubes. Each tube set imparts a slightly different sonic picture. BTW, you know the 12AU7 driver tubes impart the most sonic influence, right?? Swapping out those two "middle" tubes will change the sound the most. For my ears the PL is something I'll keep a very long time. There is great synergy in my system with the Lumin T2 and von Schweikert loudspeakers.
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