18 Sound XT120 – Ultra-Compact Elliptical 1-Inch Horn with 90° × 60° Coverage and Minimum Footprint
The 18 Sound XT120 is the most compact and widest-coverage 1-inch horn in 18 Sound’s range. With 90° × 60° constant coverage — the widest pattern of any 1-inch horn 18 Sound makes — an ESS (Elliptical Shape) design, spherical wave-front, and dimensions of just 200 × 150 × 103 mm in injection-moulded polyurethane foam, the 18 Sound XT120 is built for compact speaker systems where the horn needs to fill the widest possible listening area from the smallest possible format.
The 90° × 60° coverage opens up applications that narrower 1-inch horns can’t serve. Where the XR1064’s 60° × 40° concentrates energy for longer throw and the XT1086’s 80° × 60° covers a moderately wide area, the 18 Sound XT120’s 90° × 60° fills venues where the audience wraps widely around the speaker position — small clubs, conference rooms, retail spaces, and near-field monitoring applications where coverage angle matters more than throw distance.
The 200 × 150 mm face is the smallest of any ESS horn in 18 Sound’s catalogue. It fits on cabinet baffles alongside 8-inch and even 6.5-inch woofers without dominating the available space. The 103 mm depth keeps the horn shallow enough for the most compact cabinet designs. And at approximately 0.35 kg in polyurethane foam, the 18 Sound XT120 adds virtually nothing to cabinet weight.
The trade-off for the compact size and wide coverage is a higher cutoff frequency. The 18 Sound XT120’s 1.5 kHz cutoff is 700 Hz above the XR1064 and XT1086’s 0.8 kHz — the smaller 200 × 150 mm mouth doesn’t provide enough radiating area for low-frequency loading below 1.5 kHz. The constant directivity engages at 2.5 kHz — later than the XT1086’s 1.4 kHz and the XR1064’s 1.6 kHz. For systems crossing over at 2 kHz or above, the 18 Sound XT120 provides fully controlled coverage. For systems crossing over below 2 kHz, the larger XT1086 or XR1064 are the better choices.
18 Sound designed the 18 Sound XT120 for sound systems where top quality is required from the most compact format possible. The horn contours were developed using Computer Aided Finite Element Analysis and extensive testing.
Design and Construction of the 18 Sound XT120
The 18 Sound XT120 uses an ESS (Elliptical Shape) flare profile with a 25 mm (1-inch) throat entry expanding to a 200 × 150 mm elliptical mouth. The ESS geometry uses an asymmetric mouth — 200 mm wide for 90° horizontal coverage, 150 mm tall for 60° vertical coverage — matching the mouth dimensions to the different coverage requirements in each plane.
The 200 mm horizontal dimension provides the mouth area needed for 90° horizontal pattern control at 2 kHz and above. The 150 mm vertical dimension establishes 60° vertical control from 2.5 kHz. These are higher starting frequencies than the larger XT1086 and XR1064 achieve — the smaller mouth is the reason. Horn directivity is governed by the relationship between mouth dimensions and wavelength. At 2 kHz, the 200 mm horizontal dimension is approximately one wavelength — the minimum required for meaningful directivity control.
The constant coverage maintains 90° × 60° from 2.5 kHz through 16 kHz — approximately three octaves of consistent pattern control. In the horizontal plane, consistent response begins at 2 kHz. In the vertical plane, it begins at 2.5 kHz where the smaller 150 mm dimension finally reaches the critical fraction of wavelength needed for control. Above 16 kHz, the coverage begins to narrow as wavelengths become too short for the mouth geometry to prevent beaming.
The 1.5 kHz cutoff frequency is the lowest frequency at which the horn provides useful acoustic loading. Between 1.5 kHz and 2.5 kHz, the horn loads the compression driver but directivity is transitioning — coverage is wider than the nominal 90° × 60° in this zone. Below 1.5 kHz, loading diminishes and the output rolls off. For 1-inch compression drivers with 2–2.5 kHz recommended crossover frequencies — such as B&C’s DE10 (2.5 kHz), DE12TC (2.2 kHz), DE14 (2.2 kHz), and DE14TN (2.2 kHz) — the 18 Sound XT120 provides loaded bandwidth at the crossover point.
The injection-moulded polyurethane foam construction matches the XT1464’s material. Polyurethane foam is exceptionally lightweight — a cellular structure with high stiffness-to-weight ratio that provides acoustic damping without the mass of aluminium or composite. The material eliminates horn resonance and vibrations, producing clean output without horn-body-induced coloration.
The trade-off versus the diecast aluminium XR1064 and XT1086 is thermal management. Polyurethane foam is a thermal insulator. It doesn’t draw heat from the compression driver — the driver runs at its own temperature regardless of the horn material. For sustained high-power operation, this means more power compression from the driver compared to an aluminium horn. For moderate-power applications where thermal management is less critical — small venue PA, near-field monitoring, conference sound, retail background music — the thermal difference is negligible.
The spherical wave-front is produced by the ESS flare geometry. The sound expands spherically from a virtual point source at the horn’s acoustic centre, avoiding the reflections and phase disturbances that diffraction-based horn designs can produce. The spherical expansion means the 90° × 60° coverage pattern translates consistently from near-field to far-field.
The flat front profile integrates cleanly with cabinet baffles. The 18 Sound XT120 sits flush against the baffle surface without protruding, producing a visually clean and acoustically smooth transition from horn to baffle. The compact 103 mm depth is the shallowest of any ESS horn in 18 Sound’s range — keeping internal cabinet volume consumption to a minimum.
18 Sound developed the horn contours using Computer Aided Finite Element Analysis. The FEA process optimises both the acoustic flare geometry and the structural integrity of the polyurethane body, ensuring the horn maintains its dimensional accuracy and acoustic performance over its operating lifetime.
At approximately 0.35 kg, the 18 Sound XT120 is the lightest horn in 18 Sound’s entire range. It weighs less than half the XR1064’s 0.85 kg and roughly a third of the XT1086’s 1.0 kg. In multi-cabinet installations or portable systems where per-cabinet weight adds up, the XT120’s negligible mass is a genuine practical advantage.
Performance and Applications for the 18 Sound XT120
The 18 Sound XT120 provides 90° × 60° constant coverage from 2.5 kHz through 16 kHz when loaded with a suitable 1-inch exit compression driver. The 90° horizontal is the widest of any 1-inch horn in 18 Sound’s range — matching the 1.4-inch XR1496C’s horizontal coverage from a 1-inch format.
The wide coverage makes the 18 Sound XT120 ideal for short-throw and near-field applications. In small clubs, the 90° horizontal fills the room from a single speaker position. In conference rooms, it covers a wide table layout. In retail spaces, it provides even background music coverage. In near-field monitoring, it provides a wide sweet spot for the listener.
The 60° vertical is wide enough to cover audiences at different heights without critical speaker placement. The generous vertical coverage makes the 18 Sound XT120 more forgiving of mounting angle than tighter-coverage alternatives — there’s more room for the listener to move vertically before falling outside the coverage window.
The choice across 18 Sound’s 1-inch horn range illustrates three distinct design philosophies.
The XR1064 provides focused 60° × 40° in a compact square aluminium body. It has the lowest cutoff (0.8 kHz), lowest constant-directivity start (1.6 kHz), aluminium thermal management, and a rotatable structure. It’s the focused, thermally managed choice for systems crossing over at 1.5 kHz or above.
The XT1086 provides wide 80° × 60° in a larger elliptical aluminium body. Same 0.8 kHz cutoff, constant directivity from 1.4 kHz, aluminium thermal management, vibrationally analysed structure. It’s the wide-coverage, thermally managed choice for systems crossing over at 1.5 kHz or above.
The 18 Sound XT120 provides the widest 90° × 60° in the most compact elliptical polyurethane body. Higher 1.5 kHz cutoff, constant directivity from 2.5 kHz, no thermal management, lightest weight. It’s the maximum-coverage, minimum-size choice for systems crossing over at 2 kHz or above.
The 1.5 kHz cutoff and 2.5 kHz constant-directivity start mean the 18 Sound XT120 is best paired with 1-inch compression drivers that cross over at 2 kHz or higher. B&C’s compact 1-inch range — DE10 (2.5 kHz), DE12TC (2.2 kHz), DE14 (2.2 kHz), DE14TN (2.2 kHz) — all cross over above the XT120’s constant-directivity threshold, making them natural partners. For 18 Sound’s own 1-inch drivers with lower crossover recommendations, the larger XR1064 or XT1086 with their 0.8 kHz cutoff are the better matches.
The 18 Sound XT120 pairs with any 1-inch exit compression driver from any manufacturer. The 25 mm throat is universal.
Conclusion – 18 Sound XT120 Horn
The 18 Sound XT120 is the widest-coverage, most compact, lightest 1-inch horn in 18 Sound’s catalogue. The 90° × 60° constant coverage from 2.5 kHz to 16 kHz provides the broadest listening area of any 18 Sound 1-inch horn — matching the 1.4-inch XR1496C’s horizontal coverage from a package that measures 200 × 150 × 103 mm and weighs approximately 0.35 kg.
The trade-off is low-frequency reach. The 1.5 kHz cutoff and 2.5 kHz constant-directivity start are higher than the XR1064’s and XT1086’s 0.8 kHz cutoff and 1.4–1.6 kHz directivity onset. The smaller mouth simply doesn’t have the radiating area for sub-1.5 kHz loading. For systems crossing over at 2 kHz or above — which includes most compact 1-inch two-way systems — the 18 Sound XT120 provides fully loaded, fully controlled 90° × 60° coverage from the crossover point upward.
For compact PA tops, small venue installations, conference systems, near-field monitors, and any application where a 1-inch horn needs to deliver the widest possible coverage from the smallest possible package, the 18 Sound XT120 is the horn that maximises coverage while minimising everything else. Ninety degrees horizontal, 60 degrees vertical, 200 × 150 mm, 103 mm deep, 0.35 kg — the 1-inch horn for builders who need to fill the room from a package they can hold in one hand.
VIEW MORE 18 Sound PRODUCTS HERE.
About 18 Sound
18 Sound products are proudly made in Reggio Emilia, Italy, combining advanced technology with Italian craftsmanship. Known for their high-performance professional audio components, 18 Sound is a trusted name in the global audio industry. Their state-of-the-art manufacturing and strict quality control ensure exceptional reliability and sound clarity. 18 Sound products are designed to meet the demands of speaker builders and audio professionals, 18 Sound offers premium products with outstanding value and performance worldwide.
