I presently have the Lector 0.6t CDP and upgraded to a pair of well tested Telefunken 12AT7s from Vintage Tube Services. The improvement was not subtle. I have also tried some of the RCA 12AT7 black plates and liked them, but not enough to permanently displace the Teles. Call Andy at Vintage Tube Services and discuss what you are looking to accomplish. He is an interesting individual and should be able to help you out.
