Spaceman Ixion Optical Compressor

The Spaceman Ixion is a stompbox take on the optical compressor circuit made famous in the studios all over the world by the legendary Teletronix LA2A rack unit.

That device, with its two knobs for Gain and Peak Reduction (plus a switch to deliver compression or limiting), belonged squarely to the “less is more” approach to dynamic processing, and had an almost magical way to adapt its attack and release according to the signal it was fed. But it was most famous for its transparent way to even out vocals, bass, clean guitar tones, or any other sound that passed through it.

The Spaceman Ixion uses a similar optical circuit (with “a feedback sidechain tapped directly after the gain control element”) but offers a little more flexibility through an original, super-quiet discrete analog design that delivers that same smooth compression – with a maximum ratio up to 6:1, so no limiting here, which has an ?:1 ratio.

The most important feature here is probably the Mix knob, which allows pulling off what studio engineers call parallel compression, i.e. mixing the compressed signal with the clean one to retain some of the original dynamics.

The THRESH knob, lets you pick the level at which the compressor starts working – turning down to for more control over quieter moments in your performance, or up for a more dynamic and subtle tone.

The CONTOUR knob is a bass frequency enhancer delivering deep bottomless bass response that works great for bass, while the TREBLE control, neutral in the center position, will boost or cut high-end frequencies.

Here’s how it sounds:

Spaceman Ixion Optical Compressor

The Ixion is an extremely smooth, clean, and low-noise optical compressor that gives you an astronomical amount of variation, depth and dimension. It features an ultra-wide tonal palette, comprehensive controls, and an exceptional signal-to-noise ratio. You get the gain-reduction power of an optical photocell, a parallel-compression mix control, and Spaceman’s signature discrete FET stages.

The Ixion also provides numerous sidechain features like an equal-loudness filter, an external input jack for signal processing or use with an external expression pedal. There’s also harmonically rich make-up gain, a treble-centric tone control, and the ability to accept up to 18V for higher headroom. Regardless of your configuration, the Ixion always offers the fattest, juiciest tone with a warm, vintage appeal. Use it on guitar, bass or your tabletop and push beyond boundaries into uncharted realms of sonic possibility.

For the Ixion, we’ve chosen an optical element, in shunt formation, with a feedback sidechain. There are a number of design features that set this squeezebox apart from the pack though. The typical arrangement for a feedback sidechain would be to tap it after the make-up gain stage. In our case, the sidechain is tapped directly after the gain control element. A prominent example of this arrangement is the famous LA-2A studio compressor.

The maximum compression available is 6:1, and plenty of beautiful harmonically rich make-up gain is on tap, and available for use as vintage grit if desired. The feel of the compression will adjust to your playing, traditional attack and release parameters will vary as the pedal reacts progressively to your dynamics. THRESH, or the amount of signal needed to trigger compression, can be adjusted independently of the make-up gain. This makes it a simple task to compensate for differing instruments, and signal-chain placements. An extremely useful option included in the sidechain is the CONTOUR knob which controls an A-weighted equal loudness filter implementation derived from IEC 61672:2003 and ISO 226:2003. This emulates the way people hear the relative loudness of different frequencies, and gives the Ixion a unbelievably deep bottomless bass response. Compared to simpler high-pass filters in many compressors, you’ll find the filter here to feel quite different, bassists in particular will rejoice at the ease of maintaining low-end integrity. Finally, the sidechain itself may be accessed on its own, for experimental swelling, and bizarre ducking tones. The sidechain jack is configured as RING-SEND, and TIP-RETURN, opening up very interesting possibilities such as using an expression pedal to control compression, putting other pedals into the sidechain, or even triggering compression remotely with a completely different audio source.

The magic of an optical compressor lies in its photocell, which has a gradual and predictable release curve, with a rapid initial release and a smooth full release. It also exhibits memory, meaning its release time depends on the intensity and duration of light exposure. To fully appreciate the benefits, experience it for yourself.

The signal path of the Ixion is carefully constructed using only discrete components. To compliment the tremendous bass of the Ixion, a treble-focused tone control has been included, which is neutral when centered, treble-boosted when clockwise, and rolled off when counterclockwise. The MIX control is also quite integral to balance the right amount of natural tone and dynamic feel, and for parallel compression techniques that have become so prevalent. The capability to run at higher voltages, offers greater headroom for active instruments, or post drive signal chain placement. The range of control has been carefully curated to allow a diverse array of compression, and tone shaping while being quick and intuitive to use. All aspects of the Ixion have been lovingly crafted to produce a big, fat, juicy tone that you’ll never want to bypass.


  • Completely original discrete analog design
  • Smooth and low distortion optical gain-reduction element
  • Mix control for parallel compression
  • Sounds great on bass
  • Treble-centric tone control for warm/neutral/bright tones
  • Optional 18V operation for higher headroom
  • Unique equal loudness filter to control the frequency response of the compression
  • Externally accessible sidechain input with multiple routing options
  • Compression LED indicator
  • True-bypass