This site shows you different construction types of ECC81, ECC82, ECC83, E88CC EF86 - EL34, EL84 - GZ34 and other audio tubes made by Valvo, Telefunken, Siemens, Amperex, Mullard, Philips (regarding their code as xf2 and their getter ...) a.s.o. Also information about German Tube Hifi from the 60s as Klangfilm, Sennheiser, Telefunken Nordmende and many more.  

Audio Tubes l Klangfilm l German Tube Hifi l My Equipment l Contact l eBay