Rolls RM89 Eight-Channel Professional Mic / Line Mixer

The Rolls RM89 is an 8-channel professional mic/line mixer in a 1U rack-mount form factor, offering six balanced XLR mic/line inputs with individually switchable 15V phantom power and two stereo RCA source inputs. Designed for installed AV, broadcast, and live sound applications, the RM89 delivers a 96 dB signal-to-noise ratio and less than 0.025% THD for clean, reliable mixing in demanding environments.

For integrators and engineers searching for a rack-mount mixer for conference rooms, houses of worship, or broadcast facilities, the RM89 handles both microphone and line-level signals on the same input bus without external adapters. Each of the six XLR channels accepts mic-level signals down to -14 dBV or line-level balanced XLR sources up to 24 dBV, giving system designers the flexibility to accommodate diverse signal sources in a single compact chassis. The two RCA stereo source inputs extend the channel count further, making this an efficient solution for multi-source installed systems.

The RM89 includes bass and treble tone controls (+/-10 dB at 500 Hz and 5 kHz) for the source inputs, a master level control, and a mono summing function that collapses the stereo mix to mono output — essential for single-speaker distributed audio systems and 70V/100V installations. With balanced XLR output capable of driving loads at up to 20 dBV max, the RM89 integrates cleanly into professional signal chains without the need for additional output buffering.

Key Features of the Rolls RM89 Mic / Line Mixer

• 6 Balanced XLR Mic/Line Inputs: Accommodates both microphone and line-level sources on each XLR channel, eliminating the need for separate preamps or DI boxes in mixed-source installations.
• Individual Phantom Power per XLR Channel: Each XLR input carries independently switchable 15V phantom power, enabling condenser microphones to be mixed alongside dynamic mics and line sources on the same unit.
• 2 Stereo RCA Source Inputs with Level Control: Expands the effective channel count and integrates playback devices, background music sources, or auxiliary gear with dedicated level trims for each source.
• Bass and Treble EQ for Source Inputs: Provides +/-10 dB shelving control at 500 Hz (bass) and 5 kHz (treble), allowing tone shaping of source inputs without external processing.
• Mono Sum Output: Collapses the stereo mix to mono with a single control, ensuring compatibility with single-speaker or distributed mono audio systems.
• 96 dB Signal-to-Noise Ratio: Delivers a -80 dB noise floor and less than 0.025% THD, providing the clean signal integrity required for professional installed and broadcast applications.
• 1U Rack-Mount Design (19" Width): Fits standard 19-inch equipment racks, making it an efficient choice for AV rack buildouts in permanent or touring installations.

Technical Specifications

• Channels: 8 (6 XLR + 2 Stereo RCA)
• XLR Input Type: Mic level or line level balanced XLR
• RCA Input Type: Stereo line level
• Additional Input: 3.5mm (1)
• Total Connectors: 7 XLR, 3 Stereo RCA, 1 x 3.5mm
• Input Impedance (Mic): 600 Ohms, balanced XLR
• Input Impedance (Source): 22K Ohms, RCA
• Max Input Level (Mic): -14 dBV mic level; 5 dBV XLR line
• Max Input Level (Source RCA): 24 dBV
• Phantom Power: 15V DC (individual per XLR channel)
• Output Level (RCA): 14 dBV max
• Output Level (XLR): 20 dBV max
• Output Impedance (XLR Balanced Line): 100 Ohms
• Output Impedance (XLR Mic Level): 600 Ohms, balanced
• Output Impedance (RCA): 1K Ohms
• Max Gain (Mic): 60 dB
• Max Gain (Source): 26 dB
• Tone Controls: +/-10 dB at 500 Hz (Bass); +/-10 dB at 5 kHz (Treble)
• Noise Floor: -80 dB
• THD: <0.025%
• Signal-to-Noise Ratio: 96 dB
• Form Factor: 1U Rack Mount
• Dimensions (W x H x D): 19" x 1.75" x 4"