Because all the audio signals are recorded in the same audio interface,
this method ascertains the precision of the response time.
Because we take the first onset among those channels, it also ascertains
precision in the case where the object is exactly right or left
of the subject. The audio was recorded at 44.1 kHz and also the
onset detection was essentially performed after the trial using the
recorded signal. Hence, there was no processing lag introduced in
response time measurement. Figure 10 shows the audio recording
setup of a listening test trial.