AUM is an audio mixer and host for iPhone and iPad that lets you connect your music apps together — loading synths and effects as plugins, routing audio between them, and mixing it all live. To use AUM on iOS, you add channels, load AUv3 instruments and effects into them, route MIDI from a controller, and mix the result, all in one flexible workspace. It is iOS/iPadOS only, and it is a favourite for live performance and modular-style setups.
What AUM actually is
Think of AUM on iOS as a mixing desk and patchbay in one app. It does not make sound by itself — instead it hosts other apps. You load AUv3 plugins into channels, send their audio through effects, and route MIDI so a keyboard plays a synth running inside AUM. If you are new to plugins, read what AUv3 apps are first, because AUM is built around them.
Step 1: Set your audio and create channels
- Open AUM and check the audio settings — if you use an interface, select it here, and set a sensible buffer size for low latency.
- Tap to add a new channel. Each channel is a strip with its own input, effects and output.
- Add as many channels as you need — one per instrument or input source.
If you are using an interface, our guide to audio interfaces for iPhone and iPad covers the hardware side, and audio latency explains the buffer trade-off.
Step 2: Load an instrument into a channel
- On a channel, tap the instrument slot at the top.
- Choose an AUv3 instrument — a synth like Moog Model 15 or Animoog, a drum app, or a sampler such as Koala Sampler.
- The plugin opens inside AUM; you can now play it.
For sound ideas, see the best synth apps for iOS. To play those synths with feel rather than tapping the screen, connect a controller using our MIDI keyboard guide.
Step 3: Add effects
Each channel has effect slots below the instrument. Tap one and load an AUv3 effect — reverb, delay, EQ, compression or something creative. Effects run in series down the channel, so order matters. This is the same idea covered in adding effects in mobile music apps, just inside AUM’s flexible routing.
Step 4: Route MIDI
AUM has a MIDI routing matrix that decides what controls what. Open the MIDI section, then connect your hardware keyboard (or another app’s MIDI output) to the instrument you want it to play. This is where AUM shines — you can split keyboards, layer instruments, and send MIDI between apps freely.
Step 5: Mix and record
- Use each channel’s fader and pan to balance the sound, just like a hardware mixer.
- AUM can record the master output (and channels) so you can capture a performance or jam.
- Save the whole setup as a session to recall every plugin and routing later.
For broader mixing technique on mobile, see how to mix a song on your phone.
Understanding AUM’s signal flow
The thing that confuses most newcomers is that AUM is not laid out like a DAW timeline — it is laid out like signal flow. Audio enters a channel at the top, passes down through the instrument slot, then through each effect slot in order, and finally out of the channel’s fader to whatever destination you choose. Once you picture each channel as a vertical path that sound travels through, the rest of the app makes sense.
Outputs are just as flexible as inputs. A channel does not have to go straight to your main mix — you can send it to a hardware output on your interface, to a bus you have created, or even into another app for further processing. Sends let you feed the same signal to more than one place at once, which is how you build a shared reverb that several channels use rather than loading a separate reverb on each one. Keeping one reverb on a send saves CPU and gives a more cohesive sound.
How to choose your AUM setup
How you build a session depends on what you are trying to do, so decide that first:
- For live performance, keep the channel count modest and lean on lighter plugins so the CPU stays comfortable. Set everything up before the gig, save it as a session, and avoid loading new plugins mid-set — that is when glitches and dropouts appear.
- For sound design and jamming, you have more freedom to load heavy synths and stack effects, because a crackle while experimenting does not matter. Raise the buffer size to give those plugins room to breathe.
- For hosting plugins inside another app, build the smallest AUM session that does the job, since you are running it alongside a sequencer or DAW and both apps share the same processor.
As a rule, start with fewer channels than you think you need and add them as the arrangement grows. An overloaded session is far harder to mix and far more likely to glitch than a lean one.
Common AUM workflows
- Live performance rig — load your synths and effects, route a controller, and play a whole set from one screen.
- Plugin host for another app — many producers run AUM to host instruments while sequencing elsewhere.
- Audio routing hub — pass audio between apps and an interface, often alongside Audiobus.
Common mistakes to avoid
- Loading too many heavy plugins at once. iOS devices are powerful, but each synth and effect adds processing load. If you hear crackle, raise the buffer or freeze part of the chain before adding more.
- Forgetting to route MIDI. A common first-time snag is loading a synth and hearing nothing from the keyboard — the audio is loaded, but no MIDI connection has been made in the matrix. Check the MIDI section before assuming a plugin is broken.
- Not saving sessions. AUM remembers every plugin and routing in a saved session, but unsaved work is lost the moment an app crashes. Save early and often, especially before a performance.
- Setting the buffer too low for the job. A small buffer gives low latency but strains the CPU. For mixing or hosting heavy synths, a larger buffer is steadier; save the lowest settings for when you genuinely need tight timing.
Tips for stable performance
- Keep an eye on CPU — too many heavy plugins can cause glitches; raise the buffer if you hear crackle.
- Save sessions often so you never lose a routing you spent time building.
- Lock the screen orientation and use a stand if you perform live.
- Enable Do Not Disturb and close background apps before a set so notifications and stray processing do not interrupt the audio.
Frequently asked questions
Is AUM available on Android?
No. AUM is an iOS and iPadOS app built around Apple’s AUv3 plugin format, so it does not run on Android. Android users connect apps in other ways, and many of AUM’s plugin-hosting features rely on the AUv3 standard that Android does not use.
Do I need an audio interface to use AUM?
No, AUM works with your device’s built-in audio. An interface adds better inputs, lower latency and more outputs, which helps for live use and recording external instruments, but you can build full sessions with plugins using just your iPhone or iPad.
Is AUM a DAW?
Not really — it is a live mixer and host rather than a timeline-based recorder. It is brilliant for playing, routing and capturing performances, but for arranging songs on a timeline you would use a DAW like Cubasis or GarageBand, sometimes alongside AUM.
Can AUM and Audiobus run at the same time?
Yes. Many producers run both, using Audiobus to connect apps and AUM as the mixer and effects host. They overlap in places, so it is worth trying AUM on its own first; only add Audiobus when you need routing that AUM cannot handle by itself.
