Moog Spectravox Moog Semi-Modular Line

Moog Spectravox A Slice of Classic Moog for its Semi-Modular Line


A Nod to Early Synthesis Designs

Spectravox is a tribute to some of the earliest designs in synthesis, potentially marking a turning point in the turbulent Moog story.

Moog Recent Challenges

Acquisition by InMusic

In June 2023, Moog Music was acquired by Alesis and Akai Professional owners InMusic. Sources suggested most production would move away from the US.

Job Cuts and Relocation

By September, reports indicated over half of the jobs were cut, leading to Moog vacating its famous Asheville, NC home on Broadway Street in March. More recently, Moog announced the closure of its physical Asheville store.

Moog’s Response and New Developments

Official Statement

Following the 2023 layoffs, Moog’s official statement asked for an open mind as they completed some of their most innovative instruments yet.

Shift to Software

Moog’s development of plugins, like the Apple Vision Pro-oriented Animoog Galaxy, has frustrated many analog and hardware enthusiasts. However, the recent hardware polyphonic powerhouse Mariana showed promise.

Introduction of Spectravox

Success of the Semi-Modular Line

Spectravox joins the successful semi-modular line, including the Mother-32, DFAM, and Subharmonicon. It is a Eurorack-friendly unit in an elegant, wood-sided case, described as an ‘analog spectral processor’.

The Core of Spectravox: The Filter Bank

The filter bank, rarely seen in a 3U format today, harks back to Moog’s earliest designs and even further back to Homer Dudley’s 1928 Voice Operating Demonstrator.

Historical Influence and Modern Features

Moog 907 Fixed Filter Bank

The Moog 907 10-band Fixed Filter Bank, key to early Moog modulars, could emulate real-world sounds like speech, aiding in the assimilation of electronic sounds into musical realms. Wendy Carlos famously used it in her soundtrack for Kubrick’s A Clockwork Orange.

Moog Spectravox Moog Semi Modular Line 2

Spectravox’s 10 Bands

Spectravox features 10 bands, each with its own band-pass filter (except the lowest and highest bands). The filter bank is moveable, with variable resonance and frequency positioning controlled by a Spectral Shift knob.

Sound Source and Vocoder Mode

Sound Source

Spectravox expects a sound source fed through it, provided by a single Moog-grade oscillator offering pulse or saw wave shapes. It also allows for external sound sources via the Carrier input.

Vocoder Mode

In Vocoder mode, the Program input analyzes incoming sounds, such as a voice, and processes the carrier signal, creating a range of tonal shaping possibilities.

Resonance and Control

Filter Resonance

Turning up the filters’ resonance creates a resonant, woody-sounding percussion instrument. The choice of miniature knobs for VCAs, instead of substantial Moog knobs, is a minor drawback.

Tonal Shaping in Vocoder Mode

Spectravox’s Vocoder mode offers immense tonal shaping, from growling snarls to mournful drones. Finding the right noise-to-carrier mix and decay time is essential for natural-sounding movement.

The Appeal of Old-School Synthesis

Hands-On Control

Spectravox offers no presets or digital tuning, just a set of well-laid-out controls and quality sound-generating circuits. The patch bay covers nearly every base, except filter resonance, with VCA inputs and envelope-following outputs for every filter band.

Sparse but Effective Panel

The panel is sparse compared to its semi-modular siblings, with one internal LFO normalled to modulate the Spectral Shift. Spectravox encourages the use of external gear, making it a gateway into Eurorack for newcomers.


Restoring Faith in Moog

Spectravox could restore faith in Moog, reflecting its weighty heritage and fundamental quality. If this is the future direction for Moog, then the future looks bright, even if it mirrors the past.

FAQ: Moog’s Spectravox

What is Moog’s Spectravox?

Spectravox is an analog spectral processor and vocoder that joins Moog’s semi-modular line, which includes instruments like the Mother-32, DFAM, and Subharmonicon.

What makes Spectravox unique?

Spectravox features a resonant filter bank inspired by early Moog designs and the 1928 Voice Operating Demonstrator. It has 10 bands, each with its own band-pass filter (except the lowest and highest bands), and a moveable filter bank controlled by a Spectral Shift knob.

How does the filter bank in Spectravox work?

The filter bank in Spectravox is based on the Moog 907 10-band Fixed Filter Bank. It can emulate real-world sounds and is moveable, allowing for variable resonance and frequency positioning.

What sound sources can be used with Spectravox?

Spectravox can use its internal Moog-grade oscillator, offering pulse or saw wave shapes, or any external sound source via the Carrier input.

What is the Vocoder mode in Spectravox?

In Vocoder mode, the Program input analyzes the tonal properties of incoming sounds (such as a voice) and uses them to process the carrier signal, creating various tonal shaping possibilities.

How does Spectravox differ from other Moog instruments?

Spectravox combines elements of classic Moog designs with modern features. Unlike other Moog synths, its filter bank is moveable, and it offers hands-on control without presets or digital tuning.

What are the main advantages of Spectravox?

Spectravox provides a rich, three-dimensional sound with a wide range of tonal shaping possibilities. It encourages hands-on control and experimentation, making it a gateway into Eurorack for newcomers.

Are there any drawbacks to Spectravox?

One minor drawback is the use of miniature knobs for its VCAs instead of the classic Moog knobs, which can affect the tactile experience.

How does Spectravox contribute to the Moog legacy?

Spectravox reflects Moog’s weighty heritage and fundamental quality. It combines historical influence with modern features, making it a significant addition to Moog’s product line and potentially restoring faith in the brand amidst recent challenges.

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