Hardware Requirements Checklist for Voice Command

Microphone Input Gain

Microphone input gain should yield 45% - 55% peak amplitude when speaking with device close to the mouth.

Microphone Input No Automatic Gain Control (AGC)

Microphone automatic gain control (AGC) must not be present or is OFF by default.

Microphone Input High Pass Filter

Devices including or supporting Voice Command should have microphone input analog low-cut filter set at 200Hz.

Microphone Input Latency

Devices including or supporting Voice Command require pop-free audio data within 50ms of opening microphone.

Microphone Input 8 KHz Frequency Response

Devices including or supporting Voice Command require 8KHz audio frequency response in microphone circuit.

Speaker Wave Output Volume

Devices including or supporting Voice Command require high volume speaker output - 80 dB SPL A-weighted or higher.

Speaker Output Latency

Devices including or supporting Voice Command require speaker output latency of 50ms or less.

RAM Requirements

Devices including Voice Command require 6 MB or more available program RAM after the device boots with speech engines loaded, but with no contacts or media files present.

Button Support

Devices including Voice Command require:

• Hardware button trigger that launches Voice Command and does so in all device states except when the trigger is the Send or End key and a voice call is in progress.
  
• Hardware button trigger that launches Voice Command with more than 95% success rate.
  
• Hardware button trigger that launches Voice Command is described in User Guide or equivalent customer documentation.
  
• Voice Recognition or Record Button or key combination that emits VK_TRECORD on all Windows Mobile Standard, and having at least one application button on is required on a device running Windows Mobile Professional or Windows Mobile Classic to enable success using Voice Command (following installation by the end user if not included in the ROM image).