You will hear two very similar sounds.
Pay attention to see if you hear a difference.
Are you ready?
2 Alternative Forced Choice (AFC) 3-down 1-up
Stimuli and procedure
A pair of tones is played. 3 pairs with a siumilar frequency gap are played per 'level'. When in all 3 presentations per 'Level' the higher tone is identified correctly, the frequency gap between the tones is reduced for the next 'higher level'.
If an incorrect answer is given, the first item of the next 'lower level' is used for the next presentation.
Test termination
The test is finished if at one 'level N' a wrong answer has occured for a 2nd time.
Result
The frequency gap at 'level N-1' is considered the result.