Stereo Microphone Adapters

Solutions for getting stereo microphone signals into the iOS products varies from one Apple device to another, and over time those solutions have evolved along with the iOS product lines. A little history: In the early days iPod touch and iPhone devices provided analog audio lines exposed on the 30-pin accessory connector. But since the iPhone 4, iPod touch gen 4, and the first iPad, stereo microphone signals can only be delivered digitally via the USB port built into the accessory connector (30-pin or Lightning). Below are details to help you select the correct stereo microphone adapter for your Apple iOS product. But be careful: many of these devices look quite similar, and there may be subtle differences in specifications – always consult the manufacturer regarding compatibility with your Apple model.

Warning: Users connecting non-Apple hardware to their Apple devices do so at their own risk. Neither Apple nor the application developer is liable for any damage resulting from such use. Read and understand all product warranty statements before deciding whether to use your electronic devices for SDR activities.

Stereo Mic Solutions for the iPad

Many thanks to Robert K5TD for providing the following picture of his iPad set-up. It illustrates all the essential elements of getting an iPad running iSDR to receive live on-air signals.

Tom KM5H has done some excellent investigative work into using the iPad USB port for stereo microphone input. His research work, and his generous support of iSDR beta testing, are greatly appreciated and gratefully acknowledged. The information below comes as a result of Tom’s efforts.

Beginning with the first shipments of iPad devices Apple has included support for stereo microphone input via the iPad USB port. The iPad device comes equipped with the drivers providing stereo microphone support. The following YouTube video does an excellent job of describing how USB stereo microphone support works on the iPad:

As the video illustrates, there are two external devices that iPad owners will need to acquire in order to get stereo IQ signals from their RF front end QSD devices into their iPads via the USB port:

*Both devices are available directly from Apple, though you might be able to find them elsewhere at a lower price. Alternatives to the Griffin iMic device exist, and are likely to work when substituted for the iMic, such as Behringer UCA202. Other stereo microphone USB devices that are compatible with the iPad Camera Kit USB adapter are listed at this unaffiliated web site:

In addition to the “camera connector + USB audio interface” described above, there are now devices available that essentially combine those two pieces into a single unit, allowing you to connect a single stereo microphone accessory to your iPad. These include:

Sonoma Wireworks GuitarJack

BlueMicrophone’s Mikey Digital


Line 6 Mobile In

Alesis ioDock

The correct model of any of the above devices paired with your iPad should work with iSDR. For some combinations of Apple device and stereo microphone adapter it will be necessary to also purchase a Lightning to 30-pin Adapter.

Caveat: it is possible (even likely!) that the technical specs of these devices will change over time, and from one device to another. So beware that your mileage may vary regarding performance for SDR work. Please consult the device manufacturer’s web site for current performance specifications and warranty information.

Also be aware that when using most of these devices: the audio output from the iPad/iPhone will be routed to the stereo adapter’s OUT jack instead of the iPad’s internal speaker. You will need to connect headphones (or similar) to the iMic OUT jack in order to listen to the audio coming from iSDR. There is nothing that can be done in iSDR to force the audio to be routed to the iPad speaker, unfortunately.

Stereo Mic Solutions for the iPhone and iPod touch

The camera connection kit is not compatible with iPhones. So the only solution is to use one of the one-piece stereo microphone accessories listed above, possibly with a Lightning to 30-pin Adapter. Take care to choose an adapter that the manufacturer says is compatible with your model of iPhone or iPod touch.

Stereo Mic Solutions for Legacy iPhones and iPod Touch

The iPhone 3Gs and earlier, as well as the iPod touch gen 3 and earlier, utilized analog microphone input lines in the 30-pin accessory connectors of those devices. The stereo microphone adapters designed for newer Apple products will not work with these older Apple devices. And the stereo microphone adapters compatible with the older Apple devices have for the most part have been discontinued. But stereo microphone accessories for older devices can sometimes be found on eBay and similar auction sites. But beware: Not all of the older stereo microphone accessories are compatible with all families of older Apple devices. Most will not work with older iPhone devices without putting the iPhone into “airplane mode”, which disables the cell phone functionality of the iPhone. Some stereo mic accessories only work with the microphones built into the microphone accessory, and do not provide a jack for accepting audio from an external source – making them unsuitable for connecting to an RF front end. So do your research before purchasing any Apple accessory – especially old ones!

The following devices are amongst those that would work with iSDR back in the day:

1. Belkin TuneTalk Stereo (old discontinued model – check carefully for compatibility)

2. Blue Microphones MIKEY for iPod (MIKEY for iPod only: check compatibility)

3. Macally iVoice Pro (old discontinued model – check carefully for compatibility)

None of these devices will work with the iPad nor with modern iPhone and iPod touch models!