The 18-inch Sub that Really Takes Advantage of DSP

The StudioLive® 18sAI subwoofer features a robust onboard loudspeaker processor that can be accessed and controlled over a standard LAN network.

PreSonus® SL Room Control software makes customizing your speaker system as simple as connecting an Ethernet cable to a wireless router.

Not Just Powerful… Extremely Smart

Although the StudioLive 18sAI works great with other powered loudspeakers, when used with a StudioLive 312AI, 315AI, or 328AI, it forms a true four-way system. For applications that require a more linear (“flat”) frequency response between the subwoofer and full-range speaker, engage the highpass filter on the full-range AI-series loudspeaker to readjust the phase and time-alignment, keeping the full-range system in phase with the 18sAI subwoofer. Or leave the highpass filter off and enjoy perfectly phase- and time-aligned overlap at 100 Hz between full-range system and 18sAI.

Take advantage of wireless and wired communications over an Ethernet or Wi-Fi local area network for monitoring and control over custom tuning settings. Better yet, add the SL-Dante-SPK option card to create a Dante™ network. For complete details and specifications, visit

Key features:

  • 18-inch ferrite transducer with 4-inch voice coil
  • 1,000 watts Class D amplification
  • 32-bit floating point DSP with alignment delay
  • Switchable stereo/summed-mono XLR line outputs
  • Wired or wireless networking with free SL Room Control software features Network Setup Wizard, remote control over output level, HP filter, operational modes, performance modes, mute, speaker delay, 31-band GEQ, and 8-band PEQ
  • Optional Dante™ card
  • Pole insert and ergonomic handles

Technical Specifications

Acoustic Performance

ConfigurationPowered subwoofer, ported
Frequency Response (-10 dB)29 Hz to 141 Hz
Frequency Response (-6 dB)32 Hz to 110 Hz
Maximum Peak SPL135 dB


LF Transducer18" Ferrite
Voice Coil Diameter4"


TypeClass D
Total Power Output1,000W (total power without protection algorithms and limiter enabled)
LF Power2 x 500W bridged
Rated THD<0.05% (20 Hz - 20 kHz)
Dynamic Range119 dB (A-weighted)
Bandwidth20 Hz - 20 kHz
CoolingFree air convection


Amplifier ProtectionOver-current, DC, over/under-voltage, over-temperature, high frequency
Transducer Protection4-ch. multi-threat limiter


AC Power Input100-230V~, 50-60 Hz
AC Power Consumption (1/8 Power)150W


Contour PresetsNormal, Extended LF
PolarityNormal or Reverse
Delay Presets0m, 1m, 2m
Bit Depth24-bit
Sample Rate96 kHz


MaterialEucalyptus Plywood
FinishChemline™ polyurethane
GrillePowder-coated steel
Dimensions (HxDxW)23" x 24" x26"
(584.2 x 609.6 x 669.4 mm)
Unit Weight94 lbs (42.64 kg)
HandlesOne on each side

Connections and Controls

Input Channels2 line
Input Connector Types2 combo
Line Input Impedance10 kΩ
Maximum Input+22 dBu
Output Connector2 XLR (M) - throughput
ControlsSpeaker level (Variable: -12 dB to +12 dB), mono sum

DSP Preset, Delay Preset, Polarity Invert, Network Connected, Network Activity, Wi-Fi Setup, Wi-Fi On, Signal, Limit, Clip, Thermal

Please see complete mechanical drawings when building a custom case.
As a commitment to constant improvement, PreSonus® Audio Electronics, Inc., reserves the right to change any specification stated herein, at any time, without notification.