My amp is the Air Tight ATM-1, pictured below.

Anyone have opinions on which EL34's 6CA7 are "best" sounding. My definition of best for my ears, is clean highs, low to no grain, and warm bass and mids without being soft.

The ones in my amp now and which sound great, are The Penta Laboratories Inc, labelled as made in West Germany.

I am completely new to tubes, this is my first tube amp, and I am stunned by the quality of output.

Thoughts on comparable or better models, and where to source from? I am in Vancouver Canada, and don't mind ordering from anywhere worldwide.