A more modern implementation of the original at an affordable price and currently standard issue on many U.K. amps. Very durable and consistent, which is good for manufacturing, but the distortion can be slightly harsh and it lacks a little high end. This makes it more forgiving, but can sound a little dull.
The original power platform behind most high-powered British guitar stacks from the '60s onward. Output is generally between 20 and 25 watts, with pronounced midrange punch, tight low end and crisp top end that breaks up relatively smoothly and gets a little crunchy when pushed hard. It provides a great voice that stands out in a band mix as the mids tend to power their way through an overall mix. Big brother to the EL84.
These pass every Groove Tubes premium certification for micro phonics, hum, noise floor, physical operation and performance characteristics. They also analyze and match the gain-to-distortion ratio on a dynamic basis, assuring a powerful, singing tone that is rich in harmonics and balanced for longer sustain, wider frequency response and a more musical amplification experience. Quite simply the best 8-pin pentode tubes you can buy that are specifically designed and tested for musical instrument amplification. Sold as single tubes, matched duets, quartets and sextets. Standard equipment on Fender tube amps.
Groove Tubes power tubes are matched and rated in low, medium and high output levels. Most amp manufacturers bias their amps for tubes in the "medium" range and replacement of stock tubes frequently do not require re-biasing if "mediums" are purchased. For softer feel, quicker distortion and creamier tone, They suggest "lows"; for more dynamic headroom and tighter, quicker and harder overall response, They suggest "highs". Lows and highs are more likely to require re-biasing by a qualified service technician to meet your performance preferences.