
By Josh Srago, CTS
The A-700 Series mixer/amplifier is one of the most versatile and easy to install solutions in the TOA lineup. With 6 balanced mic/line inputs and 2 stereo summing RCA inputs, the A-700 Series can accommodate most input signals. To provide even more flexibility, though, the A-700 Series also includes a module slot for one of TOA's 900 Series modules allowing you to add an extra input of your choosing to the system. This means that you can add a mic input, a line input, a line matching input, or one of the special function modules for message repeating, tone generation, and even speaker EQ presets to an A-700 unit.

One of the features that can cause a little confusion about the A-700, though, is its ducking circuit. The A-700 has the ability to have up to 4 inputs as priority inputs. The ducking circuit works in a way that requires at least one input to be set up as a priority input, or a "Mute Send" input, while all other inputs that will mute would need to be set up as "Mute Receive" inputs. This is done via dip switches on the back panel of the unit.
While the switches are all individually numbered, you want to ignore those numbers as best you can and pay attention to the silk-screened numbers on the unit. Looking at the far right 4 switches, you can see that the silk-screen above the switch has no indication. Below those switches, though we see M, 3, 2, and 1 printed on the unit. These switches, when flipped to the down position, allow you to have inputs 1, 2, 3, or the module slot (M) operate as a mute send input.
Looking at the silk-screen printing above the switches we can see 1-M and 4-8. By flipping these switches to the down position you are indicating that you want that specific input to receive the mute signal whenever one of the priority inputs is in operation.
By configuring these switches correctly, you will be able to have background music duck beneath a page or perhaps an emergency message and ensure that announcements are heard clearly.
If you have any additional questions, please feel free to contact the TOA Product Support Group at 800-733-4748 from 8 am to 8 pm EST.