Groove Tubes GT-6550-R Duet Highest power pentode for use in Marshall, Hiwatt, Ampeg SVT, the GT amps and a few other higher powered amps. Also popular for HiFi amps. Excellent response, yet it's easier to push into distortion than "A" version, a little harder sounding than "C".
NEW SILVER SERIES TUBES. Groove Tubes Silver Series are tested and warranted to meet or exceed factory specifications.. Silver Series tubes are excellent for "normal" tube replacement applications and offer exceptional value.. Not recommended for the critical high gain V1