Seymour Duncan SFX-03 Twin Tube Classic



  • Volume
  • Gain


  • Bass
  • Treble


  • Volume
  • Gain


Seymour Duncan

"Boutique quality and design for the working musician." The sound is classic rock 'n roll.

The SFX-03 is a two channel guitar preamp employing premium subminiature type 6021 vacuum tubes. The 6021 is manufactured to meet the stringent MIL-E-1 specification for reliability and is optimized to provide long service life under conditions of severe shock, vibration, high temperature and high altitude. The tubes are configured with a high voltage power supply for maximum dynamic range. True bypass capabilities are provided to allow uncolored feed-through.


High-quality, two-channel, guitar preamp. Uses a duet of premium, mil-spec, subminiature, USA-made Phillips-Sylvania® 6021 dual triode tubes. Great for country, blues, surf, classic rock.


The high-plate voltage and 100% vacuum tube signal path allows the tubes to operate at their fullest potential and provide maximum dynamic range. The means you get the most gain and all the smooth tone you expect from a high-quality tube preamp. Two channels provide versatility. True bypass. Heavy duty steel chassis.

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