So you just bought an Amperex 12AX7 and it was made in Holland, right? Weeelll - not so fast.

Amperex was originally an American tube manufacturer on Long Island, NY. The Dutch tube giant Phillips bought the company after WWII. During the time they were replacing the equipment at Amperex with Dutch equipment, they imported tubes from their other plants in Europe and labelled them with the Amperex brand. After the changeover of equipment, they continued this practice of importing tubes from their European plants while making tubes on Long Island as well - labelling them all the same.

What tubes did Phillips produce in Europe? At one time or another they either owned the label or the manufacturing plant for Amperex, Mullard, Valvo, Mazda, Tungsram, Miniwatt, Dario, La Radio Technique, Phillips ECG (Sylvania) and others. They also bought tubes from Telefunken, Edison Swan, Brimar, Marconi, Ferranti, G.E.C. and others and relabelled them.

The result of all this is that you will find the Amperex label, including the Bugle Boy, on tubes made in Germany, France, Italy, England, Holland, Spain, the US, and even Yugoslavia.

Learn to read the Phillips tube codes (two short lines of numbers/letters/symbols on the bottle near the base) to find out who really made that Amperex in your hand. There are resources on the net for this. The code tells you what kind of tube it is, which engineering revision it was manufactured under, which plant it was made at, and the date of manufacture.

That's when you find out that beautiful 12AX7 with "Amperex" and the Bugle Boy on it was made at the Blackburn Works Ltd and is really a Mullard! or an Ei or ?