Akai S1100EX

16 voices and 8 individual outputs. It adds multitimbral headroom to a studio S1100.

Overview

The Akai S1100EX is not a sampler on its own. It answers the one complaint S1100 owners couldn't shake: not enough voices. It was designed only to expand the Akai S1100, and it adds 16 simultaneous voices and 8 individual audio outputs. In Voice Expansion mode that effectively doubles the polyphony. It has no front-panel controls and no sampling inputs. It uses the host S1100's interface, with MIDI for note data and SCSI for sample and edit transfers. It is a purpose-built extension for rigs where track counts were pushing limits and multitimbral arrangements needed more headroom.

Owners report two ways to use it. In Mode 1, the S1100EX acts as a fully independent S1100. It shares storage via floppy or hard disk and borrows the host's display for navigation. That turns one sampler into two separate instruments, so you can layer complex arrangements without voice stealing. Mode 2 is Voice Expansion mode, where the S1100EX and host combine to deliver 32 voices total, or 16 voices in full stereo. According to documentation, when loading samples in this mode, the S1100EX loads first, then the host follows, so playback stays synchronized. The unit has an internal FX card identical to the one in the S1100, so you keep effects processing in expansion.

It connects via MIDI and SCSI, and up to six S1100EX units can be chained on a single SCSI bus. In theory that allows massive voice counts, though such setups were rare in practice. The rear panel has a pair of audio inputs, not for sampling but for cascading audio. Route the stereo outputs of the S1100 into the S1100EX and the sound passes through both units, which is useful for processing or output routing. A headphone socket is also on the back, which some find awkward and others accept as a trade-off for rack efficiency. The host S1100 must be updated to version 2.00 firmware, which involved both software and hardware changes, including new EPROMs. Some benefits were available through software alone, but full functionality required the full upgrade.

Specifications

Key Features

16-Voice Polyphony Expansion

The core function of the S1100EX is simple: it adds 16 voices to the host S1100. Stereo sampling cuts available voices in half, and long decays and sustain pedals eat up note count, so the expansion is close to a necessity. In Mode 2, the combined system delivers 32 voices, which restores headroom for dense arrangements. Reviewers noted that moving from a 32-voice Emu Proteus to the base 16-voice S1100 "came as a bit of a shock," which made the S1100EX a logical upgrade path.

Mode 1: Multitimbral Mode

In this configuration, the S1100EX operates as a separate instrument. It shares storage but not the voice pool. It can run its own programs and respond to different MIDI channels independently, with data synchronized via SCSI and floppy disk. The host S1100's display is used to navigate the EX unit's functions, so there are no duplicate controls. This mode suits users who need more multitimbral parts rather than more voices, such as layering drum kits, bass, and pads across multiple outputs without voice stealing.

Mode 2: Voice Expansion Mode

This is the mode most owners use. The S1100EX and host merge into a single, more powerful sampler. When samples are loaded from disk, the S1100EX loads first, then the host follows, so both units have identical data. The host remains the master controller, and all MIDI sequencing routes through it. Polyphony jumps to 32 voices, or 16 in stereo, which effectively doubles the system's capacity.

8 Individual Outputs + Stereo Output

The S1100EX provides 8 individual outputs for multitimbral routing, plus a dedicated stereo output. Engineers can send different sounds to separate channels on a mixing console. Combined with the host S1100's outputs, that makes a flexible routing setup. The stereo output can be used for monitoring or for cascading audio through additional units.

Audio Cascading via Rear Panel Inputs

The S1100EX has a pair of audio inputs on the rear panel, not for sampling, but for routing audio from another unit, typically the host S1100. Connect the stereo outputs of the S1100 to these inputs and audio passes through the S1100EX, which can process or re-route the signals. That allows signal chains such as applying effects or balancing levels across multiple units.

Internal FX Card (Same as S1100)

Unlike some expanders that strip features to cut cost, the S1100EX includes the same internal FX card as the host S1100. It keeps access to reverb, chorus/flange, stereo pitch shifting, and echo/DDL effects. In Mode 1, the EX unit can run its own effects independently. In Mode 2, effects processing remains available without taxing the host's resources. Reviewers noted this as a significant advantage over simply adding a second S1100, which would need its own FX card upgrade.

SCSI and MIDI Integration

Communication between the S1100 and S1100EX happens over both MIDI and SCSI. MIDI carries note and control data, while SCSI handles sample transfers, system edits, and firmware updates. The SCSI chain supports up to six S1100EX units, theoretically allowing for 96 additional voices. In practice, most users run one or two units due to storage and power constraints. The reliance on SCSI means a compatible hard disk is required, not just for sampling but for reliable operation. Reviewers noted that Akai's optical drives worked well with the system, and disks could be partitioned for both sample storage and audio recording.

Firmware Requirement: S1100 Host v2.00

To use the S1100EX, the host S1100 must be updated to version 2.00 firmware. The update involved both software and hardware changes. Some benefits were available through software alone, but full functionality required new EPROM chips. Later firmware, such as version 3.6, improved stability and added minor features. The upgrade was not trivial. It required technical confidence or professional servicing, which may have limited adoption among casual users.

Historical Context

The S1100EX came out of Akai's S1000 series, a line that began with the S1000 in 1988 and set the standard for professional digital samplers. The S1100, released in 1990, built on that with 20-bit DACs, onboard effects, and improved dynamic range. The S1100EX was Akai's answer to growing demand for more voices and more multitimbral flexibility in studio and live settings. It let existing S1100 owners scale their systems without replacing the whole setup. The S1000 series was eventually succeeded by the S3000 series in 1993, but the S1100 and its EX module stayed in use throughout the 1990s, particularly in dance and hip-hop production, where layered, sample-heavy tracks demanded heavy voice management.

Similar items on eBay

No exact Akai S1100EX listings are live right now — these searches show current Akai and similar vintage audio gear on eBay:

As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.

Related Models

• Akai 1710L
• Akai 1720L
• Akai 202D-SS
• Akai 2450
• Akai 280D-SS