PreSonus Eris Sub 8BT 8" Powered Studio Subwoofer

The PreSonus Eris Sub 8BT is an 8-inch active studio subwoofer designed to extend the low-frequency range of compact powered monitors and speaker systems. It provides a dedicated bass channel for music production, desktop listening, gaming, and multimedia playback without requiring a separate subwoofer amplifier. Its compact front-ported cabinet is intended for home, studio, and desktop audio systems rather than vehicle installation.

A built-in 50-watt RMS Class AB amplifier powers the 8-inch composite low-frequency driver, with a specified frequency response of 30 Hz to 200 Hz. The subwoofer is designed to add defined low-end support while allowing the main speakers to focus on midrange and high-frequency reproduction. A peak SPL rating of 100 dB at one meter supports nearfield monitoring and personal listening applications.

Bluetooth 5.0 provides a convenient wireless stereo audio input for compatible phones, tablets, and computers. The Eris Sub 8BT can store two Bluetooth device pairings, though it streams audio from one Bluetooth device at a time. Wired balanced TRS and unbalanced RCA inputs provide alternatives for audio interfaces, mixers, media players, and compatible home audio components.

System integration is supported by adjustable gain, a continuously variable 50 Hz to 130 Hz low-pass filter, and a selectable polarity control. Its defeatable 80 Hz high-pass filter removes low frequencies from the pass-through outputs when feeding compatible powered monitors. This allows the subwoofer and satellite speakers to be configured as a more controlled 2.1 system.

The Eris Sub 8BT is voiced to complement compact PreSonus Eris monitors, but its line-level inputs and pass-through outputs also allow use with a range of compatible full-range powered speakers. A power-saving mode engages after 40 minutes without signal when standby is enabled. Protection circuitry is included to help safeguard the active subwoofer during normal operation.

Key Features

• 8-Inch Composite Driver: Adds dedicated low-frequency reproduction to a compact monitor system.
• 50W RMS Class AB Amplifier: Built-in amplification eliminates the need for an external subwoofer amp.
• Bluetooth 5.0 Audio: Streams stereo audio wirelessly from compatible Bluetooth devices.
• Adjustable Low-Pass Filter: Lets you set the 50 Hz to 130 Hz crossover point.
• 80 Hz High-Pass Filter: Can reduce bass sent to connected satellite monitors.
• TRS And RCA I/O: Supports balanced professional and unbalanced consumer audio connections.

Design & Installation

The Eris Sub 8BT uses a black vinyl-laminated medium-density fiberboard cabinet with a front-ported bass-reflex design. Its 8-inch woven glass fiber composite low-frequency transducer is housed in a vertical-format enclosure measuring 11.73 inches high, 9.84 inches wide, and 12.72 inches deep. The cabinet weighs 16.27 pounds.

Connect an audio interface, mixer, media player, or other line-level source to the balanced 1/4-inch TRS or unbalanced RCA inputs, then use the matching TRS or RCA pass-through outputs for powered monitors when needed. For a mono or LFE source, either the left or right input may be used. Position the subwoofer on the same side of the room as the main monitors when practical, avoid placing it tightly against walls or in corners, and adjust level, crossover, and polarity for the smoothest transition with the speakers.