18Watt.com

Hello,
If a ECC83 by Philips has the code "163 B3A5", does that mean it's a Mullard from GB? If so, then I might have made a good deal on ebay (€ 25 for a pair of NOS Philips with that code). Anyway it's too late now, as I won the auction already, but I'm curious.
Greetings
Christoph

Yes, the production code starting with a "B" means they were made in Mullard's factory in Blackburn. You did very well there!

To find out more about the codes and when your valves were made, see:
http://www.cs.helsinki.fi/u/oheinone/va ... oding.html
http://www.audiotubes.com/mullcode.htm

Wow. Thank's for the links! Now I can't wait to hear them. So far I just used the cheapest EH tubes that I could find, so I hope there will be a noticeable difference. Now I just need a third quality 12AX7...
Ciao
Christoph