- iOS includes support for USB Audio Class compliant audio interfaces connected via the Lightning to USB Camera Adapter. This includes 16 and 24-bit devices, multiple input and output channels, and sample rates up to 192 kHz.
Audio Input Path
The audio input path is automatically determined by iOS, according to the external audio hardware, if any, connected to your device. Some possible audio input and output scenarios are discussed below.
On all iOS devices, the audio input data is generally sampled at 48 kHz. Some audio input accessories may operate at lower sample rates, such as 44.1 kHz. SoundMeter allows the sample rate to be manually set, which means that, depending on the hardware, the rate may be set much lower (e.g. 8 kHz) or much higher (as high as 192 kHz on some devices).
The three typical audio input paths are discussed in greater detail on the following pages:
Prefer Speaker Output
- This option enables the built-in speaker of an iPhone to be used for audio output instead of the receiver (the small speaker near the top of the iPhone that is used when making phone calls).