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Dave Smith Instruments Mopho x4 Synthesizer Keyboard

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H88625 000000000
Product Price $999.0
  • Free Shipping (48 Contiguous U.S. States)
Open Box$879.12

Building upon the same award winning voice architecture of the Mopho and Mopho Keyboard, the Mopho x4 boasts huge sound and 4 voice polyphony in an i...Click To Read More About This Product

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Full-sized 44-note analog subtractive synthesizer

Building upon the same award winning voice architecture of the Mopho and Mopho Keyboard, the Mopho x4 boasts huge sound and 4 voice polyphony in an ideally sized, portable, and elegantly designed package. Use it to create huge unison basses, creamy leads, maniacal sequences, and ethereal pads.

Each of Mopho x4's four voices is composed of two analog oscillators, two sub octave generators, selectable 2- or 4-pole famed Curtis low-pass filter, three 5-stage envelope generators, four LFOs, a relatchable arpeggiator, and a 16 x 4 step sequencer. Its voice also comes packed with 20 modulation sources and almost 50 destinations. You can FM the filter to create metallic bell-like sounds and use the feedback path to add subtle or destructive harmonic content to your sound. Mopho x4's 100% analog signal path is powerful, monstrous, and sonically dynamic.

Work less, play more
Mopho x4 is intuitive and inviting. Every parameter is fully programmable and editable from the front panel. The controls are logically laid out, lending themselves to quick access so you can tweak knobs without missing a beat. The x4's full-sized, 44-note semi-weighted keyboard has aftertouch and velocity sensitivity. The sturdy full-sized pitch and mod wheels are freely assignable and sport smooth reliable action.

Expand your sonic horizon
Expand Mopho x4's polyphony using it's Poly Chain port. Mopho, Tetra, and Prophet '08 can all be connected to the x4 to increase its voice count. You can Poly Chain up to three Tetras with Mopho x4 to create a 16 voice analog super synth.

  • 100% analog signal path
  • Two oscillators per voice capable of producing sawtooth, triangle, saw/triangle, and variable pulse width square waves, with hard sync
  • Two sub-octave generators per voice (one octave below oscillator 1 and two octaves below oscillator 2)
  • One classic Curtis low-pass filter per voice (switchable 2- or 4-pole) with audio rate modulation, self-oscillating in 4-pole mode
  • Analog VCAs
  • Three envelope generators per voice (ADSR plus delay)
  • Feedback loop per voice with programmable level and gain
  • White noise generator
  • 4 LFOs per voice
  • Gated 16 x 4 step sequencer per voice (one sequence per program)
  • Arpeggiator
  • Glide (portamento): separate rates per oscillator
  • Full-sized, 44-note (F to C), semi-weighted keyboard action with velocity and aftertouch
  • Full-sized modulation wheel and spring-loaded pitch wheel
  • Fully programmable with four banks of 128 read-only factory programs and four banks of 128 user programs (1,024 total)
  • I/O
    • USB type B receptacle
    • MIDI In, Out/Thru, and Poly Chain
    • Left and Right audio outputs: 1/4" phone jack (unbalanced)
    • Sustain pedal input (accepts normally on or off momentary footswitch with 1/4" phone plug)
    • Expression pedal/control voltage (3.3 VDC max.) input (1/4" TRS phone jack)
    • Headphone output: 1/4" TRS stereo phone jack
    • Power supply for 100V - 240V AC operation
    • Operation manual
    • Free downloadable software editor for Mac OS and Windows

    This is one good Mopho (not a bad one)...Order today!

    • Dimensions (LxWxH): approximately 25.2" x 11.1" x 3.6" (64cm x 28.2cm x 9.1cm)
    • Weight: 9.4lb. (4.35kg)
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    Review Snapshot

    by PowerReviews
    Dave Smith InstrumentsMopho x4 Synthesizer Keyboard

    (based on 1 review)

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    Reviewed by 1 customer

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    (19 of 19 customers found this review helpful)


    Analog charm, modern features

    By shawn

    from PA

    About Me Novice


    • Easy to Use
    • Great Feeling Keybed
    • High Quality Build
    • Modulation Routings
    • On Board Sequencer
    • Touch Sensitive Keys
    • Usb Port


    • Available Demos
    • Single Low Pass Filter

    Best Uses

    • Electronica Of Any Sort

    Comments about Dave Smith Instruments Mopho x4 Synthesizer Keyboard:

    I can't believe no one has commented on this yet! All I can say is if you rely solely on the multitude of poor demos scattered on youtube, you will never be able to appreciate this synth. Also don't rely on the presets. While some of them are decent, the real magic is getting in there and turning knobs for yourself. I've used VA synths before so the interface is pretty familiar to me and easy to use. The sounds, however, have a certain aggression and warmth that push forward a bit more than any of my previous synths. Despite having only one selectable 2/4 pole lowpass filter, the modulation options overwhelm. I'm getting lovely synth bass with those beautiful pings on the release, buzzy strings, and a cornucopia of those classic synths sounds that all of us 80's enthusiasts try to mimic. Vince Clarke even expresses fondness for the mopho line and that's a man who knows synthesizers!

    I very much appreciate the build quality of this product. The knobs have a solid but slightly rubbery grip. The semi-weighted keybed has a nice spring without being too firm and doesn't give that horrible plasticky, clacking sound you get with cheap keyboards. In fact I'd have to say that this probably one the better ones I've played in a long time. My only gripe, and this is minor, is I wish the buttons were rubberized or otherwise not so plastic feeling.

    I always wanted a real analog but could never justify some of the over-hyped collector prices the older gear commands. This is a nice balance of all the charm you get from an analog, but also has all the modern technologies like aftertouch, velocity sensitivity, and usb midi. I'll be holding on to this one for a long time!

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