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SSOUNDS XTO S218
Dual-18″ subwoofer module of the XTO System, massive, defined low-end with cardioid-ready configuration for touring and stadiums.
The XTO S218 is the dual-18″ subwoofer module of the XTO System, a bandpass floor design delivering the low-frequency foundation large-format productions demand, reaching all the way to 20 Hz on 5″ voice-coil drivers. Deploy in cardioid arrays to keep energy off the stage and out of the back, with the same handle and dolly system as the rest of the system. It is the module that anchors a stadium design under the flagship elements.
Part of the XTO System
Dual-18 floor subwoofer for large-format and stadium work.
XTO stands for Xtended Touring Output. The large-format touring platform: the elements built for the longest throws and the highest output in the range, rigged and amplified as one system.
Key features
- Bandpass dual-18″ with 5″ voice-coil drivers
- 20 Hz low-frequency reach and 143 dB peak SPL
- Steerable cardioid arrays keep energy off the stage and out of the back
- Fly track and caster dolly shared across the XTO touring inventory
- 18 mm Baltic birch with Polyurea finish
- CardioSteer presets steer low-frequency energy off the stage
Specifications
Engineering data. The conditions each figure is specified under are stated below the table.
General
- Type
- Bandpass dual-18″ touring subwoofer
- Certifications
- CE · TÜV · EAC · WEEE
Components
- Low frequency
- 2 × 18″ cone drivers, 5″ coil
Acoustic
Electrical
Connections
- Connectors
- 2 × NL4 speakON (in / link)
- Pin map
- 1+/1− SUB · 2+/2− not linked
Rigging
- System
- Fly track · caster dolly · cardioid array hardware
Physical
Measurement conditions
- Maximum SPL is the peak level at 1 m, driven with pink noise at crest factor 4 to the clipping point of the recommended amplifier, with the SSOUNDS system preset applied. Full-range enclosures are specified under free-field conditions; figures marked half-space are specified over a reflecting plane, the condition subwoofers are deployed in, which adds approximately 6 dB.
- Frequency response is specified on axis at 1 m in a free field. The tolerance the figure is referenced to is stated alongside it; where no tolerance is given, the figure is the −6 dB bandwidth.
- Sensitivity is specified at 1 W into the nominal impedance at 1 m on axis, averaged across the pass band of the enclosure.
- Recommended amplifier power is the amplifier output SSOUNDS specifies for this enclosure, driven with the SSOUNDS system preset. It guides amplifier selection and is not an AES power-handling rating for the transducers.
- Nominal impedance is the manufacturer's rating for amplifier load calculation; minimum impedance across the operating band may be lower.
- Net weight excludes packaging, flight case, accessories and optional rigging hardware.
- Dimensions are stated in millimetres and exclude protruding rigging hardware, handles and connector panels unless noted.
- All figures are typical values for production units specified under the conditions above. Individual units may vary within published tolerances.
Directivity
Directivity computed by the SSOUNDS system prediction engine from this product's driver complement, the same dataset the printed data sheet uses. 1/24-octave band-power resolution; values are dB relative to on-axis.
System operation
Recommended: SSOUNDS D24X, one channel per XTO S218 (4 Ω) with the S218 preset loaded. Cardioid presets are supplied for three- and four-box arrays.
Downloads
Product documentation, free to open. No registration, no form. The data sheet is a PDF rendered from the page below it; the manual is a print page, so use your browser to print it or save it as PDF.
- Technical data sheetFull specification set with the measurement conditions for each figure, modelled response curves, safety notices and warranty terms.PDF · SS-DS-XTO-S218-EN-A4 · Rev. 2608 · Issued 15 Aug 2026
- Technical data sheet, in your browserThe same document as a page, if you would rather read it here or print it yourself.HTML print view · SS-DS-XTO-S218-EN-A4 · Rev. 2608 · Issued 15 Aug 2026
- Architectural and engineering specificationThe “shall be” paragraph for tender documents and bills of quantities, written from this product’s own specification rows. Section of the data sheet.HTML section · SS-DS-XTO-S218-EN-A4
- User manualUnpacking, connection, installation, operating limits, maintenance schedule and troubleshooting for this model.HTML print view · SS-UM-XTO-S218-EN-A4 · Rev. 2608 · Issued 15 Aug 2026
- Directivity table, horizontal axisPolar data in dB relative to on axis, in the layout a measurement rig exports, for prediction and modelling. Computed by the SSOUNDS prediction engine, not measured in an anechoic chamber.CSV download
- Directivity table, vertical axisPolar data in dB relative to on axis, in the layout a measurement rig exports, for prediction and modelling. Computed by the SSOUNDS prediction engine, not measured in an anechoic chamber.CSV download
Loudspeaker data files for prediction software (GLL and CLF for EASE), 2D and 3D drawings and certification documents are issued on request. Email support@s-soundspro.com and we will send the current release for this model.
Amplification
System amplifier named in this product's specifications.
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