Telefunken vacuum tube E88CC-TK; NOS versus brand new.
While I agree that "tube rolling" can make an audible improvement in SQ, I think of it as something one can do if one has no further understanding of electronics or skills on the workbench, the use of which can effect much bigger and more permanent positive results. More permanent because tubes age, and in doing so they change characteristics. So, for example, "matched pairs" of tubes usually will not stay matched for long. And any tube will change sound over time. But a better sounding film capacitor is for all intents and purposes, forever. |
While searching for three matched pairs of early Sixties (grey shield/external date code*) Siemens CCa’s, for my BAT CDP’s output stage, I purchased a matched pair each, of the same generation/iteration E88CC and E188CC (only those found with close balance between triodes and high mA, etc). As most probably know; the CCa was a specially tested/selected, low noise designation, used by the German and Dutch Post (more on the link). Bottom line; they all sound almost identical, in the CDP (low noise not being as critical). Nice thing about these 10K hour tubes; they just continue to test very closely balanced, between triodes and their matched-pair partner, after ten years. Makes them worth every penny, in my estimation. *The silver shield/internal date code CCa’s always sounded too zingy, to me, whether in my ARC SP-9, SP-14 (when I owned them) or- the CDP. https://www.tubemuseum.org/ProductDetails.asp?ProductCode=SH%5FCCa%5Fsingle Yeah: low supply and high demand (there’s a reason). |
