Tubes for Cal Audio Labs Alpha Processor

I never had any trouble with my Sigma or Alpha being hard on tubes, but I was using 10kHr Telefunken ECC803S tubes. If you enjoy transparency and quiet background; they, or Siemens E83CC's(triple mica, from the 60's) are a very good bet(both very accurate, extended in highs and lows w/o glare or bloat, and faithful to the original signal). If you prefer a warmer coloration: Mullard long plates from the 50's are very popular. Either Brimar or Mullard CV4004's will cost less and still please you, if you like the Brit sound.

Mr N- I should have mentioned: You'll never appreciate what your Alpha ia capable of unless you try NOS tubes in it. Nothing currently manufactured can come close to the reproduction of the tubes I listed(except perhaps this one: (http://www.musicdirect.com/product/73403). You'll think you upgraded the DAC.