Horizontal Axis

[Jason]

Hi.,

My iPhone is 2G OS 3.01.
Run SSP FFT Analyzer , This Horizontal Axis at 0.0KHz~4.0KHz Only, Why ever?

How do seting to 0~20KHz axis.

Thanks,

Jason

[FaberAST]

Hello Jason,

If you use the built-in microphone on the 2G iPhone, the sample rate is limited to 8 kHz, which is why you can only analyze signals up to 4 kHz. If you use a headset microphone, or a dock connector input, the sample rate will be 48 kHz, so you can analyze signals up to 24 kHz.

You might want to read some of the related articles on the blog, starting with the entry about iPhone OS Audio Routes.

Ben

[Jason]

Hi.. Ben

Thanks for the help.   


Jason