The early to mid 1960's Amperex USA White label 6922 is the one to get for the money. Great, defined, strong bass, neutral mids and beautiful highs. The good, older Mullards from the late 50's through the 60's are smooth and sweet, but more lush than the Amperex I mentioned. The bass with the Mullards is full and rich, but not as fast. The Amperex 7308 US white labels (1960's) are also nice, but a tad drier sounding than the 6922 versions and more expensive. Telefunken 6922's are fantastic in the areas of imaging, detail and clarity, but do not have as much "body" to the mids and bass, and are BIG money.