The Garmin GMA 340 Audio Panel features innovative LED-illuminated push button controls that allow audio selection of both NAV and Comm audio. Large buttons activate the Comm microphone and audios for the two  Comm transceivers to simplify cockpit workload.  Another feature of the GMA 340 is the Split Comm, which allows the pilot to transmit/receive on Comm 1 and the co-pilot to transmit/receive on Comm 2  (always helpful in obtaining ATIS, or conversing with Flight-Watch for weather updates).  MASQ^™ processing reduces ambient noise from the avionics inputs. Comm transmit indication is also provided.  Speaker selection is available to monitor the aircraft radios or to make PA announcements.  Inputs exist for altitude alert warnings from the S-TEC 55 autopilot.  In addition, the GMA 340 includes a six-place VOX intercom with three selectable modes of isolation, stereo music inputs (for external CD or Cassette players), and independent pilot, co-pilot, and passenger volume control. Each microphone input has a dedicated VOX circuit to ensure that only the active microphone is heard when squelch is broken.  Special cabin noise de-emphasis circuitry enhances cockpit communications. Also standard is the three-light Marker Beacon Receiver/Indicator with high/low sensitivity selection and marker audio muting.

N945DB also has an emergency outside transceiver antenna built into the panel, allowing emergency transceiver operations with a handheld transceiver.

Read what Private Pilot magazine had to say about the GMA 340: