It's probably one of the most misunderstood things about vacuum tubes: The name on the tube is the company that made it right? Well actually the answer is No - and that's why it can be so confusing. The tube...
My Mullard / Amperex 12AX7 ECC83 makes a brilliant flash when the amp is turned on - is this a bad tube? Nope - the "flash" is perfectly normal and it's a trademark characteristic of Mullard / Amperex tubes....
Here's a quick and easy guide to help you understand the rim numbers which reveal a speaker's manufacturer and its production date. We'll use my picture below as an example. The speaker reads C10N C7438 5 on...