DBX 640M – 6x4 Zone Processor with LCD and Link Bus

Product Overview

The DBX ZonePRO 640M is a 6-input, 4-output rack-mount digital zone processor built for small-to-mid-size commercial audio installations that demand front-panel visibility, pre-configured architecture, and system expandability. This dbx zone processor for conference rooms, boardrooms, and multi-purpose rooms includes four independent six-segment lightpipe output meters, an informative front-panel LCD, and user-assignable controls — giving on-site technicians real-time signal monitoring without a connected laptop. The 640M manages up to four independent audio zones from six input channels, including four balanced mic/line inputs that make it well-suited to paging and sound reinforcement in commercial meeting spaces. Ethernet and RS-232 control enable third-party integration with AMX and Crestron systems.

Product Description

The 640M accepts six inputs: four balanced mic/line switchable Euroblock terminal block inputs with hardware-adjusted preamp gain per channel, and two mono-summed pairs of unbalanced RCA source inputs. Two configurable input insert positions and one output insert position allow channel-specific DSP modules to be added to the pre-configured signal architecture, maintaining the system scalability expected of a commercial-grade zone processor.

Each of the four output zones includes dbx AutoWarmth — a psychoacoustic function that maintains full low-frequency bandwidth at reduced listening levels — alongside per-zone EQ, dynamics processing, and delay. The link bus duplicates audio channels to a second ZonePRO unit, enabling the system to scale beyond four output zones without running additional source cabling from the rack. Mic preamp performance includes 30–60 dB of gain range, +15 VDC phantom power, and EIN below -118 dBu at 150 ohm source impedance.

Control options include Ethernet, RS-232 serial, and the full range of optional dbx ZC wall panel Zone Controllers for occupant-level source and volume management. The front-panel LCD reports source selection, page steering, zone volume, and mute status, while four independent lightpipe meters operate from -30 to +20 dBu. ZonePRO Designer's Configuration Wizard guides integrators through setup in a step-by-step workflow.

Key Features

• 6 Inputs / 4 Outputs — Four balanced mic/line switchable Euroblock inputs and two mono-summed RCA pairs feed four independent output zones.
• Hardware Mic Gain Control — Per-channel hardware-adjusted microphone preamp gain eliminates the need for external gain stages when mixing microphone sensitivity levels.
• Front Panel LCD and Metering — Four six-segment lightpipe output meters (-30 to +20 dBu) and an informative LCD display provide real-time signal status without a connected laptop.
• AutoWarmth per Output Zone — Psychoacoustic low-frequency compensation maintains natural tonal balance at low listening levels across all four zones.
• Link Bus for System Expansion — Duplicates audio channels to a second ZonePRO device, allowing the installation to scale beyond four output zones without additional source cabling.
• Pre-Configured Architecture with Insert Positions — Fixed signal flow with two input and one output configurable insert positions provides DSP flexibility within a structured framework.
• Ethernet and RS-232 Control — Network and serial control support remote access and integration with AMX, Crestron, and other third-party control systems.
• Optional ZC Wall Panel Controllers — Compatible with the complete dbx ZC wall panel series for end-user source selection and volume management at each zone.
• Wizard-Driven Configuration — ZonePRO Designer's step-by-step wizard accelerates system commissioning for AV integrators and systems technicians.
• dbx Type IV Conversion — Greater than 119 dB A-weighted dynamic range and 0.003% THD+N maintain signal transparency through the full processing chain.
• Phantom Power — +15 VDC phantom power on mic inputs supports condenser paging microphones without external power supplies.
• UL/IEC/EN Certified — Meets UL 600065, IEC 60065, and EN 55013 for commercial-grade installation compliance.

Typical Applications

• Boardroom
• Conference room
• Huddle room
• Commercial meeting space
• Multi-purpose room
• Training room
• House of worship

Technical Specifications

Frequently Asked Questions

Q: What distinguishes the DBX 640M from the DBX 640?

The 640M adds front-panel LCD metering, four six-segment lightpipe output level meters, hardware-adjusted mic preamp gain per channel, user-assignable front-panel controls, and a link bus for system expansion. The 640 uses a more open architecture without front-panel metering, better suited to rack-only deployments managed purely through ZonePRO Designer software.

Q: How does the link bus work on the 640M?

The link bus duplicates audio channels to a second ZonePRO device, allowing an installation to scale beyond four output zones without running additional source cables from the equipment rack.

Q: Can the 640M integrate with Crestron or AMX control systems?

Yes. The 640M supports RS-232 and Ethernet control. DBX provides native Crestron and AMX control modules as free downloads from dbxpro.com, and a ZonePro Protocol Guide is available for custom third-party integration.

Q: Does the DBX 640M support phantom power for paging microphones?

Yes. All four balanced mic/line inputs supply +15 VDC phantom power, supporting condenser paging microphones without requiring an external phantom power supply.

Q: How is the 640M configured?

The 640M is configured using ZonePRO Designer software (free download from dbxpro.com), which includes a step-by-step Configuration Wizard. The software connects via Ethernet or RS-232 and supports offline programming before physical installation.

Q: Where can I buy the DBX 640M?

The DBX ZonePRO 640M is available at creationnetworks.net with pre-sales support from commercial AV specialists.