Q: I have an interface for connecting my guitar to my iPad. Why doesn’t it list any AD/DA specs?
A: All iOS devices have built-in digital audio converters — that’s how they process the sound from the internal microphones, and deliver sound to the internal speakers. Many early iOS interfaces plugged into the audio jack of an iPhone or iPad and relied on these built-in converters rather than supplying their own converters.
However, these iOS device converters were never designed for high-fidelity music production. So it wasn’t long before audio interfaces began to use the 30-pin and lightning connectors exclusively so as to use their own higher fidelity, higher bit- and sample-rate converters, such as the IK Multimedia iRig PRO.