Many folks who buy our tubes know that we use a special process to categorically rate our tubes so that players can select the tubes that best fit their preferred tones and styles. However, we get a lot of questions about our rating system, and what the numbers actually mean.

IMPORTANT BIAS NOTE: If you're replacing a tube with the SAME TYPE of Groove Tube (tube model and rating), you do not have to rebias your amp. In any other case, you should always have a qualified amp tech reset your amp’s bias whenever changing your tube type or rating number.

low

1-3

Early distortion, wide range, softer attack good for Rock and Blues solos.

Medium

4-7

Normal performance, great dynamic range/attack and best all around rating type for all styles of playing

High

8-10

Most dynamic range, most clean power/less break-up for power players, Jazz and bass amps.

Flogging Molly

Dave King: Vocals, Acoustic Guitar, Electric Guitar, BodhranDennis Casey: Electric Guitar, Acoustic Guitar, VocalsMatthew Hensley: Accordion, Concertina, Piano, VocalsNathen Maxwell: Bass Guitar, VocalsBridget Regan: Violin, Tin Whistle, Classical Guitar, Uilleann Pipes, VocalsRobert Schmidt: Mandolin, Mandola, Tenor Banjo, Five String Banjo, VocalsGeorge Schwindt: Drums, Percussion THE LIGHTS HAVE GONE OUT ON THE WORKING CLASS Three years ago, hard working men and women the world over were collectively under the assumption that their nest eggs were secure, their homes were the safest of all investments, and that the economy was on the upswing. Then, with virtually no warning, their lives were turned upside down, as an entire generation saw their dreams dashed and plans dismantled. It all happened with the Speed of Darkness. Nothing has mattered more to Flogging Molly than their new record, Speed of Darkness. "It wasn't the album we set out to write," vocalist guitarist Dave King says....

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