Rogue Audio Cronus 12AU7-12AX7 tubes choices


I own a Rogue Audio Cronus amplifier since two weeks and I want to upgrade the preamplifier section tubes which are 12AX7 and 12AU7.

First, I'm wondering the fonction of each tube. I don't want to replace the one for the phono section if it is so because I don't use this phono. What are the fonctions of each preamplifier tubes on the Cronus?

Second, I'm looking for a musical, engaging and well balance sound. What are your tubes suggestions?

Sebastien
128x128sebastienl
Anonymoustao,

Well, let's continue off topic because I don't have other way to communicate with you. First, I still use Harbeth SHL5 and I really appreciate them. In the last year, I had the chance to try many amplifiers with them. I had a great time with two Luxman and I like both the L-505u and L-590AII. The 505u have a dryer bass with the SHL5 but on every aspects, the L-590AII is more interesting with these speakers: voices so natural, fabulous sound of strings instruments, easy on the ear, refine, musical and organic.

The main reason I went back to a "cheaper" amplfier ($2000 vs. $9500) is that I judge that in my system and budget limitation it wasn't worth it. So, I switch back to the Rogue Audio Cronus, which we talk in this thread.

Surprisingly, with the Harbeth, the Cronus does things that even the L-590AII didn't. Good for me! The soundstage is wider and deeper and the timber of intruments are more accurate.

The influence I had to go with the Rogue is that my Harbeth dealer often demo them with Harbeth speakers and that combination plays MUSIC! So, I demo the Cronus at home and enjoy it. It was my first time with EL34 tubes amp and I like it so much. I don't have any regret about the switch I made and I've got back few thousands in my pocket.

Finally, if you'd like to have other information on this subject, we could create a new thread. I'll be happy to contribute.

Let me know.
I've tried RCA clear tops in both the pre-amp and the driver positions. I found them lacking in body/fullness in the former but, with warm pre-amp, phase splitter and power tubes, good in the driver openings. They have really nice, extended highs.
Is there any of you that use 6211 tubes instead of the 12AU7? I know that they are not compatible with every amplifier but when they can, they are a good improvement.