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Seymour Duncan SFX-04 Twin Tube Mayhem

Tube-powered Guitar Preamp/Overdrive Pedal
Item ID: SFX04

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Seymour Duncan SFX-04 Twin Tube Mayhem
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Seymour Duncan - It's all about the tone!

Seymour Duncan's SFX-04 Twin Tube Mayhem performs double-duty as a high-quality guitar preamp and stellar tube-driven overdrive. The Twin Tube Mayhem uses a duet of premium, mil-spec, subminiature, USA-made Phillips-Sylvania 6021 dual triode tubes, and generates a tone that's great for old school metal, new metal, thrash, death, and doom. The key to the SFX-04's great sound is its ability to run high-plate voltage, allowing the tubes to really cook, creating face-melting tones. Take your tone to new sonic heights with the SFX-04 Twin Tube Mayhem.

Seymour Duncan SFX-04 Twin Tube Mayhem at a Glance:
  • Sound
  • How it works

Sound
So how does it sound? One word: Mean! The perfect choice for any kind of aggressive music with a special leaning toward metal of any kind, the SFX-04 Twin Tube Mayhem is perfect for shredding. Plug in your guitar (with high-output Duncan pickups, of course!) and tap into the perfect metal tone.

How it works
The high plate voltage and 100% vacuum tube signal path allow the tubes to operate at their fullest potential and provide maximum dynamic range. Additional gain is achieved with a high voltage, low noise, discrete Class A input stage. The solid state input stage increases the resistance of the stomp-box to microphonics. The result is maximum dynamic range, the most gain, and the heaviest tone your expect from a great tube preamp voiced for metal. Also features a user-selectable 4dB or 8dB boost for pre-setting rhythm and lead levels, true bypass, and a fully encapsulated toroidal transformer for quiet operation. A heavy duty steel chassis ensures years of reliability.

Seymour Duncan SFX-04 Twin Tube Mayhem Features:
  • Gain: Before Level Compensation - 97 dB, After Level Compensation - 71 dB
  • Nominal Output Level - 0.25 Vrms (-10dBu)
  • Max. output level before clipping - 5 Vrms (16dBu)
  • Input Impedance: 100KOhm
  • THD @ 100mV RMS output - .5%
  • Noise @ Output - 4mV (< 3dB hum content)
  • Boost Footswitch Gain
  • Two selectable boosts, 4dB and 8dB. No effect on tone, just increased level.
  • Active Equalization Section: Bass Control: 126 Hz, Q = 1.5, Gain = +/-12dB; Midrange Control: 596 Hz / 1389 Hz, Q = 1.5; Gain = +/-12dB; Treble Control: 2.93 KHz, Q = 1.4, Gain = +/-12dB
  • Power Consumption - 11W
  • External Dimensions - 7.50" X 6.62" X 1.96"
  • Weight - 3.15 lbs.
Your tone begins with Seymour Duncan!

Why Choose Seymour Duncan?
Quite simply, it boils down to tone. Seymour Duncan has spent the majority of his life refining the art of creating pickups. Seymour Duncan is dedicated to getting the best tone possible from his pickups, from modern metal monsters to faithful reproductions of gems from the '50s and '60s. We know tone is important to you which is why we choose to carry Seymour Duncan pickups. With the massive amount of pickups available from Seymour Duncan, you're certain to find the sound you've been looking for.

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Tech Specs

  • Manufacturer Part Number: 11995-04-120

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