Optimizing the Prima Luna Premium Integrated amp


Having had the Prima Luna Premium Integrated for about 7 months now its been one of my goals to retire the CJ PV10A I had been using for pre amp. However from the start the preamp section of the Prima Luna never seemed to measure up to the CJ in deep bass. Recently however I decided it was time to retube the 12AU7's in the CJ, sticking with trusted NOS Mullard CV4003's. Now having 2 pairs of Mullards to play with I was able to do some comparison swapping in the Prima Luna. Lo and behold, putting the Mullards in the rear 12AU7 sockets of the Prima Luna brought the low bass up to where it should be and differences become trivial swapping a variety of 12AU7's between the CJ and the front sockets of the Prima Luna

Mullard NOS CV4003 highly recommended for the back 12AU7 sockets of the Prima Luna Premium integrated. Not so recommended for both socket pairs as the combination becomes too forward in the bass. Funkwerkes 12AU7 and Prima Luna 12AU7 are in use now while I seek a quicker more neutral tube than the Mullard for the front pair.
128x128davide256
Prima Luna USA posted recently that they now support KT-120 in all their line. I got mine yesterday, the first 2 hours of break in were rocky with distortion and threw 1 bad tube fault but after that they opened up and roared. They (a) remedy the PL's lack of lower bass and bass slam (b)have more percieved dynamic range and openness. I have no desire at this point to put the KT-88's back in.
I'm still waiting for the Gold Pin Deluxe version of the KT120...the current version I own is just too inexpensive for its own good.
so after 10 days of loving the KT-120's my pre and driver complement of tubes has been turned totally upside down. The Amperex 12AT7's are out because of audible gain distortion, all NOS Mullard CV4004's now. I've rolled the KT-88's back in a couple of times but they sound so emasculated in the bass by comparison that I'm back to the KT-120's in short order
I love the sound of my recently acquired NOS Mullard 4024s (replaced my JAN Philips 12At7s due to one failing)...and they seem reasonably priced.
so just an update on current tube rolling. The KT-120's continue to sing...just plain better than the cryo GL-KT-88's all around in the amp. And tube distortion in the pre section is more mercilessly exposed. I've acquired some ribbed plate Telefunken 12AU7's for the back pre sockets, cleaner, better bass, more detail that the Siemens I was using. Flipped my entire inventory of 12AU7's through front sockets again with the Teles in back... 12AU7's just sound wrong in the front sockets, low level details fuzzy, more distortion. Had settled on some Mullard 6201's (12AT7) in front, after putting Telefunken in the back sockets they were still detailed but too bright and I isolated them as a source of low level tube distortion. The Amperex world globe 12AT7's are now back in as more musical but their bass waffles, highs are a little rolled. Likely to pop for Tele or better Amperex tubes in the next 30 days.
At this point with the Teles in I have achieved my goal of retiring the CJ PV10A pre and using the PL pre section