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All-New Tube Amp Doctor 6550A-STR Redbase

All-New Tube Amp Doctor 6550A-STR Redbase

The TAD 6550A-STR REDBASE is a premium tube designed to offer a sweet, full-bodied tone with silky highs and powerful bass range.

The TAD 6550A-STR REDBASE is a remake of the classic American GE 6550A tube with a heavy, straight glass bulb, classic construction, metal base, and excellent linearity. It features a gold control grid for outstanding low-noise performance and reliable stability.

The overwhelmingly large and precise tone, plus its robust appearance make the new TAD 6550A-STR REDBASE the first choice for high-end audio applications. The 6550A-STR REDBASE is also a perfect fit for powerful bass guitar amplifiers. It delivers a natural and three-dimensional tone with exceptional depth, pleasant warmth, and fine, subtle highs.

The TAD 6550A-STR REDBASE meets or exceeds the specifications of the classic 6550A tubes and can be used in any 6550 applications with excellent performance.

More Benefits:

  • Heavy-duty 6550
  • Sweet, full-bodied tone with silky highs and powerful bass range
  • Superb responsiveness
  • Outstanding dynamics
  • Individually tested, selected, and approved.
  • Premium matched sets available (p/n RT88x)
For more information, please visit

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