What is Premium Valve Testing?
Are your output valves matched for your amp? Just because a set of valves says “matched” doesn’t mean it’s matched for your amp. Most valve suppliers put a sticker on the valve showing the anode current and the Gm. But what were the test conditions? So you might think they must be matched. Not necessarily the case. In the UK, a number of suppliers use and maintain venerable testers such as the AVO Mk4 that […]