Infra-18 vs MartinLogan Depth i
The Depth i's power @ 8ω is 350W against the Infra-18's 400W, its high-frequency extension 120 Hz against 95 Hz, and its low-frequency extension 20 Hz against 8 Hz. Both share impedance (8Ω).
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Estimated price (community-sourced)
Around — community and catalog average, updates slowly
The Bag End Infra-18 is a professional-grade powered subwoofer system that employs an 18" direct radiating INFRA cone loudspeaker in a sealed enclosure. It features a built-in 400 watt RMS amplifier and a proprietary INFRA dual integrator circuit that provides a flat acoustical response down to 8 Hz, well below the audible range of human hearing. The system uses Bag End's ELF (Extended Low Frequency) technology, which achieves smooth and extended bass response by tuning the driver above the typical operating frequency, resulting in superior low frequency performance. The enclosure is constructed from 3/4" MDF with a black vinyl finish and includes a black nylon cloth grille. Input connections include speaker-level spring terminals and three RCA line-level inputs (left, center, right), with corresponding RCA outputs featuring a fixed 95 Hz crossover. Controls include volume and a two-position phase switch for seamless integration with satellite speakers. The amplifier is mounted on an aluminum plate on the rear of the enclosure for improved cooling and serviceability. The Infra-18 is suitable for home stereo, home theater, and project studio applications, delivering powerful, tight, and extended bass performance.
Driver and acoustic performance characteristics
Amplification power output and characteristics
Driver configuration and enclosure design
Input and output connections
Size, weight, and appearance
Specifications are community-contributed and may not be accurate or complete. Verify all details with the manufacturer before making purchasing decisions. Terms & Conditions
Components that show up alongside the Infra-18 in real systems. A verdict means the pair has been checked for compatibility and headroom — open it to see how the two get along.
The closest alternatives on specs, description and the systems they turn up in, with the specs they share set side by side.
The Depth i's power @ 8ω is 350W against the Infra-18's 400W, its high-frequency extension 120 Hz against 95 Hz, and its low-frequency extension 20 Hz against 8 Hz. Both share impedance (8Ω).
The Classic 98's power @ 8ω is 300W against the Infra-18's 400W, its high-frequency extension 120 Hz against 95 Hz, and its low-frequency extension 27 Hz against 8 Hz. Both share impedance (8Ω).
The Digital Drive Plus 18's power @ 8ω is 1.3kW against the Infra-18's 400W and its sensitivity 105 dB against 96 dB. Both share impedance (8Ω) and woofer (18").
Both turn up in the same documented systems.
The AESprit-308's power @ 8ω is 200W against the Infra-18's 400W, its woofer 12" against 18", and its low-frequency extension 25 Hz against 8 Hz. Both share impedance (8Ω).
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