Stereo Microphone inputs for iPhone, Android and other Smartphones
I'm assembling a camera rig for shooting video using the iPhone (or Android smartphone), and need dual channel (stereo) mic inputs. By default, the audio jack on these phones is 2 channel out, one channel in (TRRS type connector). So it's only possible to have mono input if using the headphone jack. Therefore, the only way to get stereo input is to use the digital input, Lightening or Micro USB connector, on the phones.
I've found several such devices that allow for mixing 2 or more inputs, and sending a stereo output to the smartphone.
Requirements:
2 mono inputs
stereo digital out through Lightening and MicroUSB connector
Device powered
Pass through charging of smartphone
Adjustable levels for each channel
Ability to power microphones
Must be small and light
Must be able to use a right angle Lightening connector at the iPhone jack. This is being used on a DJI Osmo Mobile gimbal, and there's only enough space for a right angle connector.
Would be nice to have:
XLR inputs
mini plug inputs (This will keep the device more compact, since I won't need a mini plug to 1/4in adapter.)
Available Options
Saramonic SmartRig+Di (with Lightning Connector for iOS) - 2-Ch XLR/3.5mm Microphone Audio Mixer (Phantom Power Preamp, Guitar Interface)
Price: $149
Includes:
2 mono inputs
XLR Input
1/8 inch jacks
1/4 inch jacks (Through XLR plug)
stereo digital out through Lightening connector
Adjustable levels for each channel
Ability to power microphones
Missing:
Device powered
Pass through charging of smartphone
Extras Needed to make it work:
90 degree lightning connector - The quality of these is questionable.
This adapter doesn't do any audio mixing, but it is the digital interface between an analog mixer and the iPhone's lightning connector. With this adapter, you can use just about any analog mixer.
The problem that I still have with this is that I need to be able to use a right angle lightning connector at the phone.
One of the main problems with this is that it doesn't charge the phone. A lightning cable splitter is required, and introducing more 3rd party dongles is a recipe for stuff not working when you need it to.
Price: $59.95
Includes:
Stereo input
stereo digital out through Lightening
Device powered
Missing:
Pass through charging of smartphone
XLR Input
1/8 inch jacks (Uses 1/4 inch jacks)
Adjustable levels for each channel
Ability to power microphones
Looks very compact
Extras Needed to make it work:
Audio Mixer
90 degree lightning connector - The quality of these is questionable, and not sure if they work for this application because they say no data transfer.
This seams sort of ideal, but is unfortunately oriented to connecting a guitar in rather than line level inputs. The line in is stereo, but I can't figure out if it splits that stereo if no guitar is connected. Also, it appears that the gain knobs only control the individual inputs. If you did connect 2 mics through the line in, only one gain knob would be used for both mics.
Price: $149
Includes:
2 mono inputs
stereo digital out through Lightening and MicroUSB connector
Device powered
Pass through charging of smartphone
Adjustable levels for each channel
Looks very compact
Missing:
Stereo Line in only has 1 gain control
Guitar line in is not suitable for microphone inputs
XLR Input
1/8 inch jacks (Uses 1/4 inch jacks)
Extras Needed to make it work:
Micro USB to USB female adapter (This is required so that a right angle lightning connector can be used)
Price: $99
Includes:
5 inputs
stereo digital out through Lightening and MicroUSB connector
Device powered
Adjustable levels for 3 channel
Missing:
Pass through charging of smartphone
XLR Input
1/8 inch jacks (Uses 1/4 inch jacks)
ZOOM U-242in/4out, Handy Audio Interface
Includes:
2 inputs
XLR inputs
1/4in inputs
USB out
Device powered (Maybe only through regular USB?)
Pass through charging of smartphone
Adjustable levels for each channel
Ability to power microphones
Missing:
1/8 inch jacks (Uses 1/4 inch jacks)
Large and clunky
Extras Needed to make it work:
Apple Camera Connection Kit
Includes:
2 inputs
XLR inputs
1/4in inputs
USB out
Adjustable levels for each channel
Ability to power microphones
Missing:
1/8 inch jacks (Uses 1/4 inch jacks)
Large and clunky
Device powered
Pass through charging of smartphone
Extras Needed to make it work:
Have to use the iRig PowerBridge if you want to power the iPhone, but the Powerbridge doesn't provide power to the iRig Pro Duo
http://www.ikmultimedia.com/products/irigproduo/
Others that might work
By using the Apple Camera Connection Kit, there are many other USB devices that could work. Charging the iPhone will still be a problem while using the ACCK.
