Alto TS18S 18-Inch Powered Subwoofer

Alto TS18S 18-Inch Powered Subwoofer – 2500 W of Dedicated Low End

The Alto TS18S is a powered subwoofer built to take over the bottom two octaves of a PA system so the full-range speakers above it can work on vocals and detail instead of bass. An 18-inch woofer with a 3-inch high-temperature voice coil is driven by an onboard Class D amplifier rated at 2500 watts peak, in an internally braced MDF cabinet with a published maximum SPL of 137 dB at one metre. It is the largest subwoofer in Alto’s TS series, aimed at DJs, live bands and venues whose programme material lives in the low frequencies.

Low-frequency output is specified honestly and usefully: frequency response runs from 29 Hz to 100 Hz within 3 dB, extending to 27 Hz at the minus 10 dB point. That is genuine sub-bass territory, covering the fundamental weight of kick drums, bass synths and electronic dance music rather than the upper-bass thump smaller cabinets emphasise. Electronic clip, thermal and transducer overdrive protection watch over the driver during long, loud sets.

Key features

• 18-inch woofer with a 3-inch high-temperature voice coil
• Class D amplifier rated at 2500 W peak
• Maximum SPL of 137 dB at 1 m
• Frequency response from 29 Hz to 100 Hz (-3 dB)
• User-selectable EQ tunings: Off, Live and DJ
• Phase alignment selector at 0, 90, 180 and 270 degrees
• Two combo XLR and 6.35 mm inputs with two XLR outputs
• Internally braced, front-ported MDF cabinet with a 36 mm pole socket

Tuning the handover to your tops

A subwoofer earns its place in the crossover region, where it meets the full-range cabinets. The TS18S gives you two practical tools for that junction. The selectable EQ tunings shape the low end for different work: a flatter response for live sound, a lifted response for DJ playback, or bypassed entirely. The four-position phase alignment selector helps the sub and tops add together instead of cancelling around the crossover point when the cabinets cannot sit in the ideal position, which in real venues is most of the time. Volume, a signal and clip limiter indicator and a power switch with LED complete a simple, gig-proof rear panel.

Connections and cabinet

Two combo XLR and 6.35 mm inputs accept balanced or unbalanced line-level feeds from a mixer, controller or processor, and two XLR outputs pass the signal onward to full-range speakers or a second subwoofer. The front-ported MDF cabinet is internally braced to stay composed at high output, finished in a mark-resistant splatter-spray coating, and fitted with side handles, a 36 mm pole socket on top for mounting a full-range cabinet above it, and threaded inserts for casters. At 678 x 531 x 627 mm and 42.2 kg it is a two-person lift, sized and built for regular loading rather than occasional use.

Who it suits

The TS18S suits mobile DJs, live sound providers, houses of worship, clubs and event spaces running TS-series or comparable full-range tops that need a single, self-powered low-frequency anchor. It replaces no full-range speaker; it completes one, adding the physical weight that makes a PA feel finished at dancefloor and concert levels.