Seymour Duncan SFX03 Twin Tube Classic Distortion Pedal

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

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. Fully encapsulated toroidal transformer for quiet operation. Heavy duty steel chassis.

The Twin Tube Classic is a two-channel guitar preamp that uses a duet of subminiature 6021 dual-triode vacuum tubes and is voiced to evoke the classic sounds that define rock and roll. The new-old-stock, USA-made Phillips Sylvania 6021s represent the pinnacle of tube technology. They were designed and manufactured to meet the U.S. Government's MIL-E-1 spec for reliability under conditions of severe shock, vibration, and temperature. They provide extremely long service life and exhibit virtually no tendency toward microphonics.

High-quality vacuum tubes are only part of the key to a great-sounding tube preamp. Too often, inexpensive tube gear runs in "starved plate mode," where the tubes function like clipping diodes and do not actually amplify. The Twin Tube Classic employs a fully encapsulated, toroidal transformer to achieve the high plate voltage required for true tube amplification. The 100% vacuum tube signal path with a high-voltage power supply allows the tubes to operate at their fullest potential. The result is maximum dynamic range, the most gain, the smoothest tone, and the low-order harmonics one expects from a great tube preamp.

The Twin Tube Classic is a two-channel device, with a volume and gain control for each channel. It effectively provides three channels to a single-channel amp: Rhythm, Lead, and bypass. Voiced for classic rock tones, the Rhythm channel goes from a hint-of-grit to moderate crunch and the Lead channel goes from chunky overdrive to thick distortion. The Twin Tube Classic also features true bypass with gold relays, up to 90 dB of gain, a silent switching circuit designed to eliminate pops and clicks when changing channels, and a heavy-duty chassis with a candy copper paint job and stylish "chicken head" knobs. A 16-volt AC transformer is also included.

Technical Info

Gain before level compensation:
-- Rhythm channel: 74dB

-- Lead channel: 98dB

Gain after level compensation:
-- Rhythm channel: 52dB

-- Lead channel: 76dB

(Gain measured at 500Hz)

Nominal output level:
-- Rhythm channel: 0.4 Vrms (-5dBu)

-- Lead channel: 0.5 Vrms (-4dBu)

(Nominal output level measured with 100mV 500Hz input signal and all controls set to 12 o'clock).

Maximum output level before clipping: -- 2 Vrms (+8dBu)

(Maximum output measured with all controls set fully up).

THD: 3% @ 1 Volt RMS output

Harmonic spectrum @ 1Vo: predominantly 2nd harmonic with minor amounts of 3rd harmonic @ > 20dB below.

Noise at output:
-- Rhythm channel: < 3 mV (< 3 dB hum content)

-- Lead channel: < 10 mV (< 3 dB hum content)

(Noise measured with all controls set fully up and input shorted).

Power consumption: 10.4 W

External dimensions: 7.50 X 6.62 X 1.96 in. (190 X 168 X 50 mm)

Weight: 3.15 lbs. (1.43KG)

Two-channel tube preamp in a pedal! Gain and volume controls for each; global bass and treble. High plate voltage for wide dynamic range. True bypass.