"Groove 6L6B tube fits the bill for my old Silvertone amp. Replaced my RCA blacks with them!"

This reviewer purchased this item from Same Day Music.

Feature:
The rating system will allow you to chance to the same tubes as before once you bias them, however; one should always have the new sets installed and biased by an amp tech for optimum performance. GT Tests and guarantees tubes for tone, noise, shorts, gas and matched conductance / plate current and must pass the muster for vibration.

Quality:
For new tubes, I have found many amp techs prefer the GT due to the low failure rates. The tech can't be guessing which NOS tubes will work well and not fail.

Value:
Best prices around for the quality.

Desirability:
Tubes are well branded, and look quality. They are matched and tested values on the tubes. No guess work.

Sound:
This set of tubes are performing well and a 1965, 1484 Twin Twelve Silvertone amp. Recently refurbished electronically, with all new caps, resistors and biased checked. The speakers are C12Q Jensen and are vintage. I replaced the NOS RCA Blackplates with the 5 Rated tubes from Groove. I hoped to get close to the RCA tubes but it is not possible. I am rating the Grooves against the RCA 6l6 Black Plates. The GT B 6L6's are good value. I will save the RCA tubes for recording sessions. The RCA tube NOS are THE BENCH MARK for old R&R tone. I recommend the GT, ALWAYS !!! let your amp. tech. install and bias for best tone & performance.

Support:
Call up GT and you will all the help you need!

Overall:
1 Year ... tubes wear out over time and I play a lot. I understand the Groove company has there own tooling for the NEW BLACKPLATE design 6L6 this will help all TONE FREAKS to get there FIX at a reasonable and repeatable price.