Audio Fidelity Testing
Updated: July 2, 2012
The Windows Hardware Certification Program for Windows 7 and Windows 8 defines a minimum bar for audio fidelity quality. To validate fidelity quality, the test requires a specific piece of testing equipment: the Audio Precision (AP) SYS-2722 audio analyzer.
Given the expense of the equipment, alternative methods of creating test results provide some valid audio fidelity compliance options for system submissions.
Options for Submitting Audio Fidelity Tests
The audio fidelity tests validate a line output jack. Microsoft has developed tests that are designed to be used with an audio analyzer, which is described below. OEMs are expected to validate specific PC audio implementations by using the test kit (WLK 1.6 or Windows HCK) and this hardware. Options 1 and 2 are available to OEMs.
Option 1 - In-House Testing
Option 2 - Leveraged Resource Testing
Note: The imported log files must have identical audio 4-part PNPID and pin configuration.
There are five keys advantages to successful audio solutions:
Audio fidelity affects the entire Windows experience because audio is an integrated part of it. Audio fidelity has migrated away from the levels that were achieved by Consumer Electronic (CE) devices. The decline of audio quality is apparent, and Windows users are taking notice.
Three different metrics are measured today that directly affect the end user:
Current Audio Fidelity Testing
The Fidelity Test verifies that the audio device meets the WLP requirements for a high-fidelity audio playback experience. The test plays a tone that is analyzed by an Audio Precision System Two device that is connected to the analog output jack of the system. The following test are evaluated:
Audio Precision Machine Requirements
The Fidelity Test requires an Audio Precision 2700-series machine. This needs to include at least the following modules and filters:
The following are not required for the audio fidelity test:
AP models 2702, 2712, and 2722 with A-weight and AES-17 filter packages installed meet these requirements.
Importing Test Logs for Audio Fidelity Tests
OEM partners who want to import Audio Fidelity Test logs from an outside resource can use the following third-party test houses. These test houses are equipped with Audio Precision analyzers for audio and system testing.
Note: This information is provided for informational purposes only and Microsoft makes no warranties, either express or implied, therein. All URLs and other Web-site references are subject to change without notice. The entire risk for the use of this information remains with the user.
Windows Certification Program Requirements: http://msdn.microsoft.com/library/windows/hardware/hh833793
Setup Verification Details: To ensure that DCOM is working correctly, download DCOMTest.exe from
http://support.microsoft.com/kb/259011/ and follow the instructions there.
Additional fidelity test documentation is available in the Windows HCK help documentation at http://go.microsoft.com/fwlink/p/?LinkID=252774.