The Akai AX73, launched in 1986, was a significant achievement in affordable analogue synthesis and introduced some unique feature not found on any other analogue synthesizers. This full-featured programmable polyphonic synthesizer stands out with its distinctive light grey control panel and impressive six-octave keyboard — a full octave more than most competitors of its era. Despite being an analogue instrument with a single oscillator per voice, the AX73 demonstrates considerable power and versatility, surpassing even Akai's own 2-oscillator AX80 in capability.

The instrument follows the classic VCO-VCF-VCA signal flow architecture, similar to Roland's celebrated Juno series (6/60/106), proving that single-oscillator designs can deliver compelling results when properly implemented. Strong oscillators combined with built-in chorus ensure rich, full-bodied sounds rather than thin, weak tones. The synthesis engine offers exceptional flexibility in its filter section, LFOs, and envelope generators, providing straightforward yet comprehensive sound-shaping capabilities.

Programming is handled through Akai's DAC (Digital Access Control) system, utilizing a 10-digit keypad for parameter selection with adjustments made via a value slider or key pair. While DAC isn't the fastest programming interface, Akai enhanced usability by allowing users to skip through parameters using forward and reverse keys in edit mode. The same keys navigate through patch programs in bank mode. A contrast-controllable backlit LCD display, coupled with edit/compare facilities, further streamlines the programming experience.

The AX73's slightly weighted, velocity-sensitive keyboard delivers excellent playing feel — firm and responsive. Velocity sensitivity can be assigned to affect either tone (VCF cutoff) or volume (VCA), adding expressive performance capabilities. The envelope generators offer standard ADSR parameters with versatile routing options to VCA, VCO and VCF, VCA and VCF, or VCO independently, providing extensive control over sound shape and tonality.

Sound-wise, the AX73 delivers 100 onboard patches characterized by crisp, clean, and precise tones. While not a "wild blitzkrieg instrument," it achieves surprising punch within its controlled sonic palette. Additional sounds can be archived to and loaded from cassette tape. Performance controls include programmable pitch/filter and modulation wheels, programmable portamento, and three keyboard assignment modes: Poly (6-voice polyphony), Dual (3-voice with double oscillator power), and Uni (monophonic).

A particularly innovative feature is the AX73's integration capability with Akai's sampler line, specifically the S612 and the flagship S900. Using Akai's 13-pin Exclusive output connection from the sampler, the AX73 can program MIDI splits to assign sampler voices to specific keyboard zones. Crucially, the synthesizer's complete parameter set can be applied to shape and modify incoming samples. The final output can combine the original sample, the AX73-edited version of that sample, and one of the AX73's internal programs simultaneously—creating extraordinarily rich textures. These sample edits, along with MIDI split configurations, can be stored as part of patch programs, demonstrating thoughtful design and forward-thinking integration.

The AX73 represents an instrument users can grow with — starting as an accessible analogue polysynth with quality factory sounds and progressing to become a powerful sample-editing controller when paired with Akai samplers. As part of Akai's expanding ecosystem including sequencers, MIDI mixing desks, a 14-track recorder, and the VX90 expander module (based on the AX73), this synthesizer marked Akai's definitive arrival as a major force in electronic musical instruments.

Technical Specifications

Synthesis

• Type: Analogue subtractive synthesis
• Architecture: VCO-VCF-VCA signal flow
• Oscillators: 1 per voice
• Polyphony: 6 voices
• Keyboard Assignment Modes: Poly (6-voice), Dual (3-voice, double oscillator), Uni (monophonic)

Keyboard

• Keys: 73 (6 octaves)
• Type: Slightly weighted
• Velocity Sensitivity: Yes (assignable to VCF cutoff or VCA)

Filter Section

• Configuration: VCF with extensive routing options

Envelope Generators

• Type: ADSR (Attack, Decay, Sustain, Release)
• Routing Options: VCA / VCO and VCF / VCA and VCF / VCO

LFO (Low Frequency Oscillator)

• Waveforms: 5 selectable waveforms
• Modulation Targets: VCO, VCA, or VCF
• Parameters: Variable speed and depth, programmable delay

Effects

• Built-in Chorus

Memory & Storage

• Patch Memory: 100 programmable patches
• Voice Naming: 12 characters
• External Storage: Cassette tape (load/save additional sounds)

Programming Interface

• System: DAC (Digital Access Control)
• Input: 10-digit keypad for parameter selection
• Adjustment: Value slider and value keys
• Navigation: Forward/reverse keys for parameter scrolling (edit mode) and patch selection (bank mode)
• Display: Contrast-controllable backlit LCD
• Features: Edit/Compare facilities

Performance Controls

• Pitch/Filter Wheel (programmable range)
• Modulation Wheel (programmable range)
• Portamento (programmable)

Connectivity & Integration

• MIDI Split Programming: Yes (assigns external MIDI sources to keyboard zones)
• Sampler Integration: 13-pin Exclusive connection (Akai S612/S900)
• Sample Editing: Full parameter control over incoming samples
• Combined Output: Simultaneous layering of original sample, edited sample, and internal AX73 program
• Storage: Sample edits and MIDI splits storable within patch programs

Physical Characteristics

• Panel Color: Light grey
• Design: Clean, distinctive, and obvious control layout

Related Products

• Compatible Samplers: Akai S612, Akai S900
• Expander Module: Akai VX90 (based on AX73 architecture)