When connecting an iPhone or iPad to an audio mixer.
First, the voltage levels do not match.
Voltage Levels
| Level Type | dB | Volts |
|---|---|---|
| Line Level (0VU) | +4dBu | 1.228 volts RMS |
| Line Level Consumer | -10dBV | 0.316 volts RMS |
| Instrument Level | -20 dBu | |
| Microphone Level | -60dBV to -40 dBV | 0.001 to 0.01V volts RMS |
- 0dB is 1V RMS
- 0dBV is 0.775V RMS
Attenuation Links
Passive Attenuators
https://www.electronics-tutorials.ws/attenuators/attenuator.html
Stereo line level to mono microphone level
https://electronics.stackexchange.com/questions/87787/stereo-line-level-to-mono-microphone-level
Line level signal to microphone input adapter
https://www.epanorama.net/circuits/line_to_mic.html
All About Pads
http://www.uneeda-audio.com/pads/
Using iPad/iPhone headphone jack for audio input
\https://gmondada.wordpress.com/2017/03/28/using-ipadiphone-headphone-jack-for-audio-input/