Well, I only had it for a week, and haven't yet opened the top plate, so it's been the stock 6L6GC. I will enjoy the current setting for a while and will experiment EL34 (which I look forward to very much) after I get some clear ideas of the current sound.
I bought the speakers first so I don't have much experience with other speakers with CS600. The comparison of CS300XS/CS600 was done with Lawrence Audio Violin, driven by AMR DP-777. The results were consistent with what I have now.
My purchase of M30.1 was based on the reviews of course and also on my fond memory with P3-ES2 that I had for a while. Although it lacked the bass and scale compared to Proac 2.5, the midrange was fabulous.
So what are the improvements of the current system compared to my other Proac-based system? The key areas are:
(a) Smoother midrange/highs with reduced grain around the voice/instruments. More air.
(b) Deep deep sound stage, but this may be in part attributed to the fact that I can place the speakers well into the room (5 ft from the back wall) which was not possible in my US home living room.
(c) More "authoritative" bass. I wouldn't call it tighter, but weighty yet well defined. It's hard to describe, but it sounds more realistic without feeling muddy. I've been thinking about this matter lately. Although we all seek for "tight" bass, when you go to the jazz concert the bass sound is actually not that tight.
In my 20+ years of this hobby, the most memorable upgrade was changing Adcom GFP-555 to Melos SHA-Gold. I had never expected that a preamp alone could make such a difference. The Leben CS600 upgrade will now be put on near top of my list. Saying this in comparison with a system that is more than decent in any audiophile standards should be quite a testament. I realize I am sounding like a salesperson, but I am in no way affiliated with Leben or any companies mentioned. Just a music lover enjoying good sound.
