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  • Electro-Harmonix Bass9 Bass Machine

    By Chris Loeffler | (edited)


     Is there more to this than the bass frequency spectrum it produces?


    Guitar players of heavier music (not to be confused with “heavier guitar players”) have always been envious of the low-end space bass and synths get to occupy, dropping to D, C, and even entire octaves down with the help of pitch shifters. While much of this is in the service of sounding “darker” or accommodating a vocalist, I’ve seen quite a few players go low to fill in bass parts (either while their keyboard player was occupying the higher registers, to throw down dueling bass with their bassist, or for laying down scratch tracks while songwriting). What quickly becomes apparent is there is much more to the bass than the frequency spectrum it produces, from attack to percussive contributions… which is where the Electro-Harmonix Bass9 Bass Machine comes in.

    Electro Harmonix has been the master of polyphonic guitar synthesis for over a decade now, crafting the tones and character of sitars, keyboards, and synthesizers from a standard guitar pickup’s signal. The Electro-Harmonix Bass9 Bass Machine brings nine different bass emulations to the electric guitar player, with controls for Dry, Effect, CTRL 1, CRTL 2, and mode. The Bass9 features buffered bypass, wet/dry outs, and runs on a standard 9.6v 200mA power supply.


    What You Need to Know


    The Electro-Harmonix Bass9 Bass Machine shares a shared format with all the EHX 9-series pedals… single input, Wet/Dry output, independent level controls for Wet and Dry, nine genre-specific sounds, and two variable parameter controls to fine-tune a given mode.

    The nine modes included in the Bass9 are designed to fit the various applications of bass over the last 50 years. Here’s a list of the settings as described by Electro Harmonix-

    1.       PRECISION – An emulation of the popular bass guitar standard. CTRL 1 controls the sub-octave, mixing between 1 octave down (counter-clockwise position) and 2 octaves down (clockwise position). CTRL 2 adjusts your tone which is modeled after the original instrument’s tone control.

    2.       LONGHORN – Inspired by the Danelectro® 6-string basses from the ‘50s, this patch is great for copping baritone style tones. CTRL 1 adjusts the pitch in half steps from -1 octave (CCW) to unity (CW). CTRL 2 controls a vintage tremolo effect which increases in depth and rate as the knob is turned up. Unique ring modulation effects are generated when the knob is turned past 2 o’clock. Also use the Longhorn preset to detune your guitar for metal!

    3.       FRETLESS – Emulation of both electric and upright fretless basses. CTRL 1 controls the buzzy growl sound of a fretless instrument. CTRL 2 adds a classic Jaco-style chorus effect which intensifies as the knob is turned up. Pro Tip: light palm mutes with your right hand produce a more realistic upright sound.

    4.       SYNTH – A big sounding bass synthesizer modeled after the classic Taurus® synthesizer. Use CTRL 1 to adjust the synth’s note range—in four sections of the knob—split between octaves and fifths. CTRL 2 adjusts the synthesizer’s envelope filter range. Higher settings of CTRL2 makes for a brighter and wider filter sweeps.

    5.       VIRTUAL – A unique patch that allows you to adjust your bass’s body density and neck length. CTRL 1 adjusts body density; higher settings produce longer, piano-like sustain. CTRL 2 adjusts neck length, where the length increases as the knob is turned clockwise.

    6.       BOWED – A classic bowed bass sound with adjustable attack. CTRL 1 controls sub-octave mixing between 1 octave down (CCW) and 2 octaves down (CW). CTRL 2 adjusts the bow’s attack speed, as you turn up the knob, the attack speed slows. The attack effect is fully polyphonic.

    7.       SPLIT BASS – This patch provides a sub-octave effect on all notes below F#3—the F# found at the fourth fret of the D-sting on a standard guitar. It does not pitch shift notes above G3. This allows a guitar player to play bass lines with the lower two strings of a guitar and chords or melody with the highest three strings. CTRL 1 adjusts bass tone by adding upper harmonics as the knob is turned clockwise. CTRL 2 provides an envelope filter/auto-wah effect on all notes you play. As you turn CTRL2 up, the wah effect intensifies. Pro Tip: turn up the DRY knob to hear your guitar signal.

    8.       3:03 – A polyphonic emulation of one of the most sought-after vintage bass synthesizers. CTRL 1 adjusts the filter’s envelope sweep depth or total range while CTRL 2 sets the envelope speed. Pro Tip: use the guitar’s volume knob as a sensitivity control for envelope triggering.

    9.       FLIP-FLOP – Inspired by the Electro-Harmonix Octave Multiplexer, this patch provides a ‘70s style logic driven sub-octave generator, except the BASS9 tracks without glitches! CTRL 1 handles sub-octave, mixing between 1 octave down (CCW) and 2 octaves down (CW). CTRL 2 adjusts the frequency of a synth-like low-pass filter.

    As you can see, the Bass9 quickly jumps from standard electric bass emulations to synthesizers, upright/cello, keyboard, and more.

    Starting with the P-Bass, I can say it sounded exactly like the P-Bass sound in my head, with attack, quack, and decay of a modern bass tone and the ability to smear and round it out by rolling back the Tone control for a more vintage sound. Of all the modes, this was the one I was prepared to be the most critical of, and a couple of minutes of experimentation had by pseudo-bass lines on a Fender single coil strat sounding dead-on. The scale and accessibility of the guitar fretboard lends itself to voicings and chording that could sound off, but that’s more about pushing beyond what the P-Bass would do.

    The Longhorn mode was a bit of a headscratcher for me, because it didn’t appear to change the voice of my guitar, just the octave. It is cool to jump down in half step increments all the way to an octave down, and the tremolo is worth its own effect; I found it to be a more natural behaving and musical version of a polyphonic pitch shifter than a totally different sound.

    The Fretless is a cool mode that is so specific I felt a touch let down. It NAILS the Jaco tone with stylized buzz and chorusing. If that’s what you’re looking for, you’re not going to find a more authentic sound without a fretless Fender Jazz bass and a MXR Digital Delay unit (Jaco’s chorus tone wasn’t achieved with a modulating chorus). That said, I would have traded the chorus control for more control over the attack envelope.

    Synth mode is monstrously sick, and instantly recalled JPJ’s sick grooves (I’ve only had the pleasure of seeing his perform with the Taurus in Them Crooked Vultures). Fat, sticky, and wet.

    Virtual is a trippy mode that feels more like instrument-building tool, with the ability to define the character of the entire sound, from ASRD to pitch.

    The Bowed setting is a combination of octave (and suboctave) down with an envelope-driven volume swell on the front end. Cello and upright bass tones were all over the lower three strings, and there are some interesting, throaty viola sounds in the 10-14 fret range on the high B and E strings.

    The Split Bass is a cool setting, reminiscent of one of the Key9 settings where the bottom three strings of the guitar register as bass (octave down, revoiced) and the top three strings either keep their original tone OR have an envelop filter (not a true auto-wah) applied for funky, clav-like keyboard parts.

    3:03 operates similar to the Synth mode, with different attack and octave effects.

    Flip Flop is another cool, if puzzling, mode that recreates the EHX Octave Multiplexer without the quirks and grunge that I identify as some of its most endearing features. It’s still dirty and low, and the undeniably more accessible response of the Flip Flop mode brings this effect into the world of repeatability, I missed the original’s erratic charm.

    My experience of early 9-series EHX pedals (well, starting with the Ravish, which isn’t technically a part of that family) was amazing sounds with a touchy input. This could be addressed by disciplined playing attack or (cheating) with a compressor placed before the effect. That said, I’ve noticed the releases of the last few pedals in this series have been significantly more forgiving of sloppy technique. I’m not sure if that’s an improvement to the algorithm or an integrated compressor, but the result is extremely accessible. It’s worth noting

    Bonus points- I played the Bass9 in P mode into the EHX Bass Mono Synth. It sounded glorious and was a testament to the power of the individual engines that the character of both pedals shone through without turning into a muddy mess.




    The EHX Bass9 needs to  be first (or at least near the front) to work well. It doesn’t appreciate overdrive or distortion sitting between it and the guitar.




    The Elector-Harmonix Bass9 Bass Machine is super cool, and a great toy for songwriting, home recording, or adding bass stylings to s live performance. It seems at once both an inevitable extension of the EHX 9 series AND a bit of an odd man. Because it does so many things so differently (more akin to the Key9 than, say, the Mel9) it can take some time to get the most out of each mode (it would be cool to save presets), with every mode seeming to push the boundaries of how much manipulation can be done to the output of passive pickups.




    Electro-Harmonix Bass9 Bass Machine Product Page

    Buy Electro-Harmonix Bass9 Bass Machine at Sweetwater (MSRP $295.10, Street $221.30)




    Chris Loeffler is a multi-instrumentalist and the Content Strategist of Harmony Central. In addition to his ten years experience as an online guitar merchandiser, marketing strategist, and community director he has worked as an international exporter, website consultant and brand manager. When he’s not working he can be found playing music, geeking out on guitar pedals and amps, and brewing tasty beer. 

    Edited by Chris Loeffler

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