1 thought on “Amperex 12ax7 Angled Foil getter

  1. This is one of the earliest European 12ax7 tubes. Produced by Amperex/Philips and predates Mullard [] getter tubes. The tubes have been produced between 1951 and 1956 and come with date code that is printed between pins – I saw it with mP1 and mPC codes. There are a lot of unusual things about the tubes. First of all, the tubes has welded plates instead of riveted. This is more expensive, but at the same time reduces micro-vibrations. The getter is attached directly to the plate and angled at 45 degrees. Then the tube has a similar getter with foil strip as the later tubes.

    The sound is a perfect example of Philips tubes of that era: Very delicate, a bit slow, highly euphoric. It is the most delicate sounding 12ax7 that I’ve experienced. This is definitely not a tube for all types of music – the best example would be vocal jazz to truly highlight the strengths of the tube. Rock wouldn’t be good as the tube is not dynamic enough for that genre.

    Back in the days they really didn’t spare any costs and it’s evident by the noise floor of this tube – it’s measuring at practically impossible -90 dB level!!! Regular 12ax7 tubes measure -82-83 dB (remember the dB scale is exponential, so this would be around 2 times quieter than regular 12ax7).

Leave a Reply