How to Mix Your iPhone Multitrack on a Teenage Engineering TX-6

You record up to four tracks in Reel the way you always would, from the built-in mic, an interface or a USB instrument. Then you plug the TX-6 in. Reel switches from being a thing the TX-6 feeds to a thing the TX-6 mixes: track one lands on the first strip, track two on the second, and so on, with Reel's master on a fifth. Press play and the song sits under your fingers, one fader per part, with the TX-6's EQ, compressor and effects available on every channel.

That used to be a hardware-recorder privilege. The TP-7 does it with the TX-6 as its party piece, and desks like the Tascam Model series do it at ten times the size. The phone version needs one cable.

A TX-6, an iPhone running Reel and the USB-C cable from the TX-6 box. On a USB-C iPhone that is genuinely the whole list. On a Lightning iPhone add Apple's Lightning to USB 3 Camera Adapter, the one with the extra power port, same as any other USB audio gear.

Power is not a worry here. The TX-6 runs on its own battery for around eight hours, so it is not drinking from the phone while you mix. And because iOS only takes one audio interface at a time, the TX-6 simply becomes that interface for as long as it is plugged in, carrying audio in both directions on the same cable.

Reel has three output modes: two channels, eight or ten. Two-channel is the normal case, a stereo master, and it is what every ordinary interface gets. Eight-channel sends the four stereo tracks to their own output pairs. Ten-channel adds Reel's stereo master alongside them on channels nine and ten.

On a TX-6 in ten-channel mode the mapping is what you would hope: each of the four tracks arrives on its own stereo strip and the master arrives on a fifth, so the ten channels occupy five of the TX-6's six stereo channels. Every part of your reel has a fader, and the whole mix is still there on its own strip if you want to ride it as one thing.

Worth saying plainly, because it is the unusual part: almost no small interface can do this. A typical two-in two-out box has exactly one stereo return, so it can only ever receive Reel's master. The reason this rig works is that the TX-6 happens to be a six-channel mixer that accepts a lot of audio back over USB. That is rare, and it is most of why the pairing is interesting.

Record your reel first, or load one from the Library. Plug the TX-6 into the phone. Open Reel's In and Out sheet, where the output routing lives, and pick the ten-channel mode. That is the whole setup: press play and bring the faders up.

From there it behaves like any mixer with stems on it. Pull the drums back, push the vocal, mute a part for eight bars and bring it back in. Reel's transport keeps working while you mix, so you can loop a section and stay in it while you find the balance, or scrub to the chorus and A-B two ideas for it.

Each TX-6 channel has a three-band EQ and a compressor, so a muddy guitar or a spiky vocal can be treated per part rather than on the sum. There are two stereo effects processors with reverb, chorus, delay, freeze, tape, filter and distortion, so a send effect on one part of a phone recording is suddenly a normal thing to do. Mutes and solos are physical. And the faders are real faders, which for performance mixing matters more than any spec: you can move two parts against each other at once, which a touchscreen never quite lets you do.

The honest counterweight, and TX-6 owners will already know it: the knobs are very small. Reviewers have been consistent about that since it launched, and mixing on it is precise but not luxurious. It is still a far better mixing surface than glass.

The cable is not one-way. The TX-6 has always been able to feed Reel, since it is a twelve-channel USB interface into the phone, so the same box that mixes your tracks today can be what recorded them yesterday: sum your gear through the TX-6, record into Reel, then flip the direction and mix the result on its faders. One mixer, both jobs.

The TX-6 also pairs with Reel over Bluetooth MIDI, which we tested against this exact unit, so the two can talk timing without spending the USB connection on it.

Be clear about what this rig is for: it is live mixing, hands on faders, out of the TX-6's headphone or line outputs. Printing the fader performance is the part to think about. A bounce in Reel prints Reel's own mixer, and Master Record captures Reel's own master, so neither of them contains the moves you made on the TX-6. The TX-6 performance exists at its outputs, which is where you would need to capture it, and we have not tested re-recording the TX-6's mix back into the phone while all ten channels play out, so we will not claim that loop works until we have.

If what you want is a repeatable printed mix rather than a performed one, Reel's own mixer plus a bounce is still the simpler path. The TX-6 rig earns its place when the mixing itself is part of the performance, a jam resolved on faders rather than a session finished on a screen.