Seymour Duncan SFX-09 Double Back Compressor Guitar Effects Pedal  

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Seymour Duncan's SFX-09 Double Back Compressor is a stompbox that won't get in the way of your unique sound. Simply put, a compressor makes quiet passages louder and loud passages quieter, making your... Click To Read More About This Product

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Seymour Duncan's SFX-09 Double Back Compressor is a stompbox that won't get in the way of your unique sound. Simply put, a compressor makes quiet passages louder and loud passages quieter, making your sound more "professional" by providing smooth dynamics and enhanced sustain. Most other compressors, however, can get in the way of your guitar's natural transients and feel”but not the Double Back. This feature, which gives this compression pedal its name, allows some of the uncompressed sound”specifically the initial "snap" of the string”to "double back" into the compressor output, thus preserving the essential essence and sensation of a guitar string being plucked. And it's extremely quiet.

At its heart, the Double Back is a low-noise, low-distortion compressor-sustainer pedal with very wide-range compression, exceptional sustain, and simple, intuitive control of compressor dynamics. One control knob adjusts the compression ratio from 1:1 to over 20:1 and simultaneously sets the maximum sustain, with an extraordinary 60dB of sustain gain being engaged at high compression ratios. Added to this are 3 features that preserve the playing dynamics and feel that are lost with many other compressors. The first is the Double Back control, blending some of your guitar's uncompressed signal with the compressed signal, thus preserving the essence and sensation of a string being plucked. The second is a 3-position switchable frequency filter, allowing the tone of this sound to be tailored to fit the music and the player's taste. The third is the Attack control, which determines how fast the compressor responds to each pick attack. The range of this control is enormous. At its fastest speed, the compressor action is almost instantaneous”the guitar sound is compressed as soon as the pick releases the string. At medium speeds, the initial organic thunk of the guitar body gets through before the compressor acts. At the slowest speed, a massive explosion of sound precedes the sustained tone, hammering out the guitar dynamics while still providing incredible sustain.

  • Compression Ratio: Adjustable from 1:1 to 20:1
    Maximum Compressor Gain: +50dB
    Attack Speed: Adjustable from 3.2ms to 23ms
    Double Back Gain: From fully off to +34dB
    Battery Life: 100 hours with a premium alkaline battery
    Power Source: 9V battery or external 9VDC regulated wall transformer, center pin negative. 5mA current drain
    Input Impedance: 1 Megohm (1000 kOhm)
    Output Impedance: 2.75 kOhms maximum
    Output Clipping Level: 7V Peak-to-Peak
    Distortion: Less than 0.3% at 300mV RMS output at 1 kHz
    Noise referred to Input: -102dBV unweighted, 400Hz ” 20kHz, input shorted
    Type of Circuitry: True bypass, class A
    Compressor type: Voltage Controlled Amplifier (VCA)
    Dimensions: 4-3/4" W x 5" L x 2-3/10" H
    Weight 1.5 lbs.
    Chassis material: 16 Gauge Steel
One year replacement warranty on all pickups.

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(12 of 14 customers found this review helpful)


A winner! The only compressor pedal out there I like.

By Robert Henson

from Atlanta, GA

This pedal does exactly what I want it to do: help fatten the tone and sustain without masking the initial string attack that defines the character of the instrument (electric upright bass in my case). These bass instruments are hard to compress because the string attack is so percussive and the note blooms slowly. The SFX-09 gives me a lot of flexibility to retain that percussive tonal quality while adding more fatness and sustain to each note.

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