AV: Sound Latency - Not all sound cards provide optimal millisecond timing [17206]

This article applies to:

E-Prime 3.0

E-Prime 2.0

E-Prime 1.x

Detail

If your experiment does not require specific sound timing, we recommend using your computer's native sound hardware and E-Prime's default sound settings.

However, for experiment paradigms that require auditory stimuli, much care and concern should be considered with the hardware being used. E-Prime reports millisecond accurate timing. This does not mean that E-Prime is capable of making hardware do things it cannot.

Sound cards can have startup latency ranging from good to poor. Startup latency is the time from when E-Prime tells the sound card to play sound to when the sound actually emits from the sound card or speakers. Not all sound cards are created equal. Results can also depend on the selected sound card driver and selected API (application programming interface). The default API used by E-Prime 1.0, E-Prime 1.1, E-Prime 1.2, and E-Prime 2.0 is DirectSound, which is the capabilities offered by DirectX. The default API used by E-Prime 3.0 is CoreAudio.

E-Prime 2.0.10.x introduced the option of selecting the sound API so the API with the lowest possible sound latency for a particular sound card may be used (see AV: Editing the SoundDevice.API for DirectSound, ASIO, CoreAudio, or Chronos [18865]).

For more information on APIs in Windows Vista and 7, please see this article: AV: Sound Latency - Windows Vista / Windows 7 (and beyond) [18833]. To determine the best API for your hardware, please see the chart below or use our Sound Tester program as detailed in this article: AV: Use of SoundTester to determine machine compatibility with ASIO or Core Audio/WASAPI [18834]. Also, note that if the DirectSound sound startup latencies reported below are acceptable for a specific paradigm, the E-Prime experiment's Sound device will not need to be configured or changed and the defaults may be used. 
 

Sound Card Startup Latency Results

Sound Card Startup Latency Results can be found in the following articles:

• TIMING: E-Prime 3.0 Timing Data [24332]
• TIMING: E-Prime 3.0 Mac Timing Data [29834]
• TIMING: E-Prime 2.0 Timing Data [19579]
• TIMING: E-Prime 1.2 Timing Data [19580]
• TIMING: E-Prime Go Timing Data [35163]
• TIMING: Chronos Timing Article [24513] 

NOTE: As a result of our tests for Windows 7 and beyond, PST generally recommends on board sound with the default High Definition Audio Device driver and the Core Audio API. In Windows Vista, we recommend an add-on PCI or PCIe sound card with the manufacturer's driver and the Core Audio API. For Windows XP, onboard sound was found to be comparable to some add-on cards.