Groove Tubes Vacuum Tubes
at the www.groovetubes.com site
So, “Why buy Groove Tubes”? It’s really simple. Electron valves have always been made in large quantities, like light bulbs. In fact, many valve manufacturers like General Electric also made light bulbs, some of the processes are very similar.
Groove Tubes buys “raw” valve stock from the surviving manufacturers, mainly in the former Soviet Eastern block countries and China, and tests it, rejecting faulty and sub-standard ones. There is no myth about where the valves come from, in fact the last letter of every GT valve tells you the country of origin, e.g. “R” for Russia, “S” for Slovakia etc. What makes Groove Tubes different is the rigorous testing each and every valve is subjected to.
Power valves are computer tested for five fundamental performance criteria. Only after they have passed these are they “Performance Matched” into Duets and Quartets, and “Distortion Rated” in relation to at what volume they will produce power amp distortion. Click here to see our Distortion Rating chart.
Preamp valves are individually tested for gain, microphonics and signal to noise ratio on a unique combination of sophisticated electronic test equipment and classic guitar amp environments. Our preamp valve testing is so strict we reject over 30% of some valve types.
Many amp manufacturers like Fender and Soldano fit Groove Tubes as standard because they can depend on consistent performance, and have recorded very substantial drop in warranty claims on their amps from customers. Click here to see “Signs your valves need changing”.
As if that’s not enough to set Groove Tubes apart from the crowd we have many “GT exclusive” designs, like the fabulous new GT-12AX7M Mullard replica, the high performance GT-E34LS, and are the only company currently manufacturing valves in the USA, the GT-6L6GE and the new GT-6CA7GE, made with the original General Electric tooling and machinery.
Finally, remember to get your amp re-biased whenever you fit Groove Tubes power valves for the first time. Click here to see our “Power Tube Comparison Chart” which includes a list of correct bias voltages for Groove Tubes power valves. The good news is, once your amp is biased for a particular Distortion Rating you won’t need to get it re-biased if you re-fit the same number valves next time round.