Mixer/Amplifier, Modular, 30 W, 8 Module Ports, Black (2U)
By: TOA
Premier Commercial Audio & Security
TOA : A-903MK2
Description
The TOA A-903MK2 are widely recognized as the industry standard in installed sound system amplification. When reliability and performance are critical – such as in paging and music distribution for airport, hospital, and industrial sound systems – you can count on the TOA 900 Series to perform consistently, day-in and day-out.
Features
A-903MK2 features include:
- Modular Eight Channel Mixer/Amplifiers for paging, background/foreground music distribution and music/messaging-on-hold.
- Proven TOA Quality and Reliability
- Engineered for High Performance with wide frequency response, very low noise and distortion, and excellent output regulation.
- Three Models: A-903MK2 (30 W), A-906MK2 (60 W), A-912MK2 (120 W)
- Eight Module Slots accept any combination of TOA plug-in modules for custom system configurations.
- 25 V, 70 V and 8 Ohm Transformer-Isolated Speaker Outputs with screw terminal connector and protective cover plate (A-903MK2: 4 ohm).
- Direct Low-Impedance Output Mode bypasses output transformer.
- Dual Mute Bus permits multiple levels of paging priority using optional mute-type modules.
- External Mute Terminals for activating mute function with external switch closure.
- Remote Master Volume Terminals for control with an external 10k ohm linear-taper potentiometer.
- Individual Channel and Master Volume Controls.
- Bass/Treble Tone Controls with tone defeat switch.
- Low Cut Switch to limit low frequency response.
- Auxiliary Output for connecting an external mixer or recording device.
- Insert Jacks for connecting external signal processing.
- Bridging Input/Output for input expansion or recording device.
- Normal, Clip, Power, Protect, and Signal Indicators provide unit status.
- Rear Panel AC Convenience Outlet for powering external equipment
- Turn-On Delay disconnects output during power-up.
- Over-current and Thermal Protection Circuitry prevents potential damage from overload, short-circuit and overheating.
- Volume Control Security Knobs Included (4)
- Optional Rack-Mount Kit, MB-25B
- UL / cUL Listed
- Five Year Warranty
Specifications
| Output Power | 30W |
| Damping Factor | Not Specified by Manufacturer |
| Input Sensitivity | Module Inputs: Varies According to Installed Modules Bridging Input: 100mV |
| Input Impedance | Module Inputs: Varies According to Installed Modules Bridging Input: 3.3 k ohms |
| Gain | Not Specified by Manufacturer |
| Frequency Response | 20Hz - 20kHz |
| Signal-to-Noise Ratio | Not Specified by Manufacturer |
| Total Harmonic Distortion (THD) | 0.02% |
| Input Connections | 8 x Input Module Slots 1 x RCA Bridging In/Out |
| Output Connectors | 8 ohm, 25V, and 70V Balanced Screw Connectors 4 ohm Unbalanced Screw Connector RCA Aux Output |
| Controls Front Panel | Power Button, Master Volume Control, Individual Channel Volume Controls, Bass and Treble Controls, Low Cut Switch, and Tone Defeat Switch |
| Controls (Rear) | Mode Switch |
| Indicators | Signal, Normal, Peak, Power, and Protect LEDs on Front Panel |
| Cooling | Not Specified by Manufacturer |
| Power Consumption | 60W |
| Dimensions (WxHxD) | 16.5 x 3.9 x 12.5" (419 x 99 x 318 mm) |
| Weight | 17.2 lbs (7.8 kg) |
| Specialties | Delayed Output Connection at Power On Protection Circuitry for Overload, Overheating, and Short Circuit Rear-Panel AC Outlet for Powering External Device |
Resources & Documents
| a-903mk2.pdf | Datasheet |