Сабвуферы — Martin Logan Grotto 15

The Grotto 15 is the larger of two powered subwoofers in the Grotto series, which MartinLogan announced on 17 October 2025 after the Dynamo Foundation, Dynamo and Abyss lines introduced in 2024. The Grotto name returns from an earlier MartinLogan subwoofer that had been out of the catalogue for years. North American launch pricing was USD 2,799.99 or CAD 3,199.99, and the only finish is gloss black.

Key specs that matter

The bass system has three 15-inch aluminium cones - one active woofer and two passive radiators. Power comes from the Magnitude MT-2kW Class D amplifier, rated at 1,000 W continuous and 2,000 W peak. MartinLogan specifies a response of 20 Hz to 120 Hz within 3 dB, measured anechoically through the LFE input. The sealed cabinet is 52.2 cm high, 55.4 cm wide and 55.4 cm deep and weighs 53.5 kg. Maximum power draw is 1,000 W, with standby consumption of 0.5 W when wireless is off and under 2 W with it on.

Engineering and use context

MartinLogan calls the arrangement a Hybrid Woofer System - the passive radiators bring the low-frequency reach associated with ported boxes, while the enclosure stays as compact as a sealed design. Aluminium was chosen for all three cones for its strength-to-weight ratio and heat dissipation. The 1-inch MDF enclosure has dual centre braces and reinforced woofer baffles to resist the forces of the driver set. Signal processing runs on a 500 MHz Vojtko DSP engine with 64-bit resolution. On the back panel sit a level knob with an LED ring, a tone sweep function, a power mode switch for On, 12 V trigger or Auto, and a wireless pairing button. Over Bluetooth, the MartinLogan app on iOS or Android adjusts level from -40 to +12 dB, the low-pass filter from 35 Hz up to the upper rated limit, phase from 0 to 180 degrees and polarity, recalls Movie, Music and Night presets, and trims the 20 to 30 Hz region by up to 10 dB either way. Integrated anti-vibration feet come with spikes for carpet.

Pairing

Wired connections include an XLR LFE input, RCA left, right and LFE inputs, speaker-level inputs on banana terminals and an RCA sub output for daisy-chaining further units. An AV receiver or processor connects through the LFE input, and the speaker-level terminals suit an integrated amplifier with no subwoofer jack. A built-in wireless receiver and supplied transmitter offer lossless, low-latency transmission with forward error correction when a cable run to the subwoofer is impractical.

Alternatives

The MartinLogan Grotto 12 uses the same hybrid layout with 12-inch drivers, rated down to 22 Hz and priced at USD 2,299.99.