JBL Professional CSMA-280 - 8-input 2 x 80W Commercial Mixer/Amplifier (70/100V and 4/8 Ω, 1U fanless)
The JBL Professional CSMA-280 is a 2-channel mixer/amplifier designed for commercial installations requiring simple operation, high reliability, and full compatibility with 70/100V or low-impedance (4/8 Ω) distributed lines . Featuring 8 mixing channels and two 80W outputs , it integrates Crown DriveCore™ technology into a fanless 1U chassis for maximum efficiency and low power consumption. The clean front panel offers input volume controls, bass and treble controls per output , and illuminated rings for easy viewing in low-light environments. The rear panel includes Hi-Z switching (automatically activates a 70Hz high-pass filter for 70/100V), switchable 27V phantom power , priority with contact closure , and VOX ducking on channels 1 and 5, independent AUX outputs for each amplifier, and an RJ-45 port for CSR-V wall-mounted volume control. Its DIP-configurable input routing allows you to conveniently assign which channels feed each of the two zones/outputs.
Main features
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Power : 2 × 80 W per channel into 4/8 Ω (1 kHz, ≤ 0.5% THD). Compatible with 70/100 V outputs without an external transformer (insertion loss ≤ 1 dB).
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Inputs : 8 channels with balanced Euroblock connectors; stereo RCA summed to mono on CH2–CH8 ; priority and VOX on CH1 and CH5 .
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Outputs : 2 power outputs (AMP1/AMP2) + AUX line outputs for each amplifier for recording/additional zone.
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Operation : Hi-Z with automatic 70 Hz HPF filter; switchable 27 V phantom power ; priority muting by contact; VOX ducking for announcements.
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Control and usability : Bass/Treble per output , illuminated rings (presence/clip), DIP routing of inputs to each output.
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Remote : CSR-V via RJ-45 (Cat 5 cable) for zone volume control.
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Design : 1U fanless (43.3 × 436.9 × 303.4 mm) with included rack kit ; GreenEdge manufacturing and high-efficiency DriveCore™ .
Audio features
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Response : 20 Hz–20 kHz (±2 dB) into 4/8 Ω; 80 Hz–15 kHz (±2 dB) into 70/100 V; AUX output: 20 Hz–20 kHz (±1 dB).
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Input sensitivities : Mic 3 mVrms · Line 0.775 Vrms · RCA 0.300 Vrms.
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Impedances : Mic 400 Ω · Line 20 kΩ (bal.) · RCA 50 kΩ.
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THD : < 0.5% (power output); 0.05% typical (line output).
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Signal-to-noise ratio : > 90 dB (A-weighted, ref. nominal power).
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Supported loads : stable from 2–16 Ω (nominal operation 4/8 Ω); outputs also for 70/100 V.
Product benefits
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Two real zones with flexible input routing (DIP) to power each 80W output with the desired sources.
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Simple operation for non-technical personnel: basic controls, illuminated rings and clear prioritization of messages/alerts.
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Installation versatility : works on low voltage or 70/100 V lines without additional accessories and with optional wall control.
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Efficiency and reliability : DriveCore™ architecture, fanless design and construction for continuous use in commercial environments.
Use cases
- Retail, hospitality and catering: background music and announcements by area.
- Education and corporate environments: classrooms, meeting rooms and hallways.
- Fitness centers, museums, and public spaces with local level control.
Frequently Asked Questions
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How do I activate 70/100 V? Turn on the Hi-Z ; the 70/100 V terminals are enabled and a 70 Hz HPF is automatically applied.
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Can I mix low Z and 70/100 V on the same channel? No. Do not connect low Z and high Z loads to the same output simultaneously.
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Is there phantom power? Yes, 27V switchable for microphone inputs.
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How many zones can I have? Two independent power outputs (AMP1/AMP2); assign the inputs to each one using the DIP switches .
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Does it support wall control? Yes, with the CSR-V panel via RJ-45 (Cat 5).
Project description
JBL CSMA-280 Mixer/Amplifier: 8 inputs (CH2–CH8 with Euroblock and RCA; CH1/CH5 with Euroblock and priority connector + VOX ); 2 x 80W outputs at 4/8 Ω (1 kHz, ≤ 0.5% THD) with 70/100V option ( Hi-Z + HPF 70 Hz); AUX outputs for each amplifier; 27V phantom power ; DIP routing of inputs to AMP1/AMP2; frequency response 20 Hz–20 kHz (±2 dB) 4/8 Ω / 80 Hz–15 kHz (±2 dB) 70/100 V; THD < 0.5%; SNR > 90 dB (A); sensitivities Mic 3 mVrms / Line 0.775 Vrms / RCA 0.300 Vrms; Mic 400 Ω, Line 20 kΩ balanced, RCA 50 kΩ impedances; CSR-V remote control via RJ-45 ; dimensions 43.3 × 436.9 × 303.4 mm (1U); shipping weight 6.9 kg ; rack kit included; fanless design with DriveCore™ technology.
