(!!!) (Best Value Pair) ECC84=6CW7 Ultron East Germany by RFT 1970's (10.5/11.5ma and 10.0/10.4ma)
(!!!) (Best Value Pair) ECC84=6CW7 Ultron East Germany by RFT 1970's (12.8/10.6ma and 11.8/11.6ma)
(!!) (2nd Best Pair) ECC40 Philips NOS made by La Radiotechnique, Chartres/France 1969 (6.1/6.7ma and 6.3/6.9ma) 1-3% matched
(!!) (Best Pair) ECC40 Philips NOS made by La Radiotechnique, Chartres/France 1969 (6.0/6.1ma and 6.0/6.1ma) 1-2% matched
(!!) (Recommended Pair) ECC40 Philips NOS made by La Radiotechnique, Chartres/France 1969 (5.5/5.6ma and 5.5/6.0ma)
(!!) (Recommended Pair) ECC40 Philips NOS made by La Radiotechnique, Chartres/France 1969 (5.8/6.6ma and 6.0/6.6ma)
(!!) (Recommended Pair) ECC40 Philips NOS made by La Radiotechnique, Chartres/France 1969 (6.0/6.5ma and 6.1/6.8ma) 1-3% matched
(!!) (Recommended Pair) ECC40 Siemens NOS made by La Radiotechnique, Chartres/France 1967-1972 (6.1/6.4ma and 6.0/6.0ma)
(!) (#1 6CW7 Best Single) ECC84=6CW7 Mullard branded Philips Miniwatt Holland 1962 (10.6/11.0ma)
(!) (Best Value Pair) ECC84=6CW7 Ultron East Germany by RFT 1970's 2-3% matched (9.6/11.6ma and 9.0/11.0ma)
6223 Sonotone USA NOS
ECC40 Philips NOS made by La Radiotechnique, Chartres/France 1967-1970
ECC84=6CW7 Mullard International NOS 1960 (8.8/12.2ma)
ECC84=6CW7 Mullard Sonotone NOS 1960 (11.2/11.8ma)
ECC84=6CW7 Siemens Germany Sonotone NOS 1959 (11.2/13.8ma)