Can windows phone 7 microphone detect frequencies in the range of 18k-19kHz?

Can the windows phone 7 in-built microphone detect f开发者_开发百科requencies higher than 18kHz?

Technically yes, the API supports recording PCM with sufficient quality to express a 18kHz sine wave. Standard POTS lines and even T1 lines generally operate at 8 kHz 16 bit which is mathematically enough to correctly record a max of 4 kHz. And since the mic isn't usually used for anything higher quality than telephony audio, I bet the limiting factor will be the hardware... your mileage will definitely vary from phone to phone.