Recording with OP-1 Field and iPhone
The Teenage Engineering OP-1 Field is a portable synthesizer, sampler, and 4-track tape recorder. Paired with Reel on your iPhone, you can capture all 4 tracks of the OP-1 Field separately over USB for mixing and overdubbing in the app.
What you need
To record the OP-1 Field into Reel you need three things: the OP-1 Field itself, an iPhone running iOS 18 or later, and a USB-C to USB-C cable.
No adapter is needed for USB-C iPhones (iPhone 15 and later). For Lightning iPhones you need Apple's Lightning to USB 3 Camera Adapter.
Setting OP-1 Field to 8ch USB mode
By default, the OP-1 Field sends 2 channels over USB (stereo mix). To record all 4 tracks separately you must switch it to 8ch mode.
On the OP-1 Field, go to System, then USB MODE, and set it to 8ch. This exposes 8 mono channels over USB: tracks 1 through 4 in stereo pairs (1L/1R, 2L/2R, 3L/3R, 4L/4R).
Connecting to Reel
Connect the OP-1 Field to your iPhone with the USB-C cable. Open Reel. The app automatically detects the OP-1 Field as an 8-channel input device.
In the Input settings, you can route each OP-1 Field track to a separate Reel track. Track 1 of OP-1 goes to Track 1 of Reel, and so on.
Recording all 4 OP-1 tracks at once
Arm all 4 tracks in Reel, hit record, and play your arrangement on the OP-1 Field. Each OP-1 track is captured to its own Reel track in 32-bit float.
You now have 4 independent stems you can rebalance, overdub, effect, and export separately.
Using the original OP-1 (not Field)
The original OP-1 only sends 2 channels over USB. You cannot record all 4 tracks at once. The workaround is track-by-track recording.
On the OP-1, mute tracks 2, 3, and 4, then arm Reel track 1 and record. Rewind Reel, unmute OP-1 track 2, mute the others, arm Reel track 2, and record again. Repeat for tracks 3 and 4. You now have 4 separated stems in Reel.
Adding overdubs in Reel
Once the OP-1 Field tracks are in Reel, you can overdub new parts directly into the app. Plug in a microphone or instrument to another channel of your USB interface, or use a second pass through the OP-1.
Reel lets you punch in and out at any point, so you can fix a bad take or add a solo over an existing section without re-recording anything else.
Frequently Asked Questions
Can I record the OP-1 Field into my iPhone?
Yes. Connect the OP-1 Field to your iPhone with a USB-C cable and open Reel. The app automatically detects it as a USB audio device.
How do I record all 4 OP-1 Field tracks separately?
Set the OP-1 Field USB MODE to 8ch in System settings. This exposes each of the 4 tracks as a separate channel pair. Route each one to its own track in Reel and arm all 4 for recording.
Does the original OP-1 support multi-track recording over USB?
No. The original OP-1 only sends 2 channels over USB. To capture all 4 tracks into Reel you must record one track at a time by muting the others on the OP-1 and arming the matching track in Reel.
What cable do I need to connect the OP-1 Field to an iPhone?
For USB-C iPhones you need a USB-C to USB-C cable. For Lightning iPhones you need the Apple Lightning to USB 3 Camera Adapter plus a USB-C cable.
Can I overdub on top of OP-1 Field recordings in Reel?
Yes. Once your OP-1 Field tracks are in Reel, you can overdub vocals, instruments, or additional OP-1 parts on the same tracks or on new ones.
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