Leben CS600 owners, what tubes have you rolled?

The KT-120s are the best I've had in my CS600 to date. Easily besting the 6n3ce.

@Kujocku - 6L6GC/6P3S-E/EL34s

All - drop the kt120s in. You won't be disappointed. Better everything but your cover comes off.

Popin the top never sounded soooo goood

kujocku, the 6L6GC's were 6L6GC (5881) SOVTEK, the stock tubes that came with the Leben CS600. Not the blackplates from the 60s.

bolero32, the KT120 are Tung Sol's and yeah, the cover must be removed to accommodate their height.

bolero, if you have the dough, get a couple/few quads for your leben. Sure you can replace the rectifier too (since they're cheap but I didn't notice a change when I swapped mine out.)

Pick a quad set and leave in for a long while 3-6 months. Remember the music you'd be critically listening with (note: strengths, weaknesses - highs/midrange/bass); swap the quad out for the next you're interested in and play the same critical listening music as afore - take and compare notes again.

Again, the KT120s are amazing in the CS600 (enough so that I have another quad waiting in the wings). I'm just enjoying the music these days without the urge to roll for a long while.

I haven't had any of Jim's recommended ones in my amp with the exception of the rectifier: 6CJ3 GE NOS.

The mixed 6CS7 quad and 6L6GC-STR's sound interesting tobesure and yes IMO would be better than the original CS600 tubes.

Enjoy