The Siemens CCa tubes are worth every penny of the +- $250 that they cost. I use them in both my Sonic Frontiers Line 3 SE+ preamp and in my Wolcott P220M amp and there is simply nothing else that comes even close.
Do an A/B comparison to anything else out there and you will change to them despite the price - they are that good.
Do an A/B comparison to anything else out there and you will change to them despite the price - they are that good.