How can I use my phone as a MIDI input?

What is MIDI?

MIDI stands for Musical Instrument Digital Interface, and is a technical standard that describes a communications protocol, digital interface, and electrical connectors that connect a wide variety of electronic musical instruments, computers, and related audio devices for playing, editing and recording music (The History Of MIDI).

The MIDI standard was published in 1983 and standardized in 1988, allowing different digital music devices and electronic instruments from different manufacturers to connect and communicate with each other (History of MIDI – Hosa Technology). This was revolutionary, as prior to MIDI, electronic musical instruments from different companies were incompatible with each other.

At its most basic level, MIDI allows one device to control another. For example, a MIDI keyboard controller can be used to control settings on a MIDI-capable synthesizer to generate sounds. MIDI also allows digital musical data (signals, notes, parameters, etc.) to be transmitted between devices, enabling complex music productions.

Why Use a Phone for MIDI Input?

Phones are ubiquitous and easily accessible computing devices that most people carry with them everywhere. This makes them a convenient and portable option for MIDI input compared to bulkier hardware MIDI controllers [1]. Additionally, most modern phones have touchscreens, allowing them to double as control surfaces by assigning different screen areas to MIDI controls. The large number of sensors packed into smartphones also enable innovative approaches like using device motion for expression [2].

Another major advantage of phones for MIDI is wireless connectivity. Both Wi-Fi and Bluetooth allow using the phone as a cable-free MIDI controller to connect to synths, DAWs, and other music gear. This gives greater flexibility in studio setups and live performance situations compared to wired connections [3]. In summary, the ubiquity, touchscreens, motion sensors, and wireless connectivity of phones make them a versatile option for MIDI input.

Enabling MIDI on Your Phone

To use your phone as a MIDI input, you first need to enable MIDI functionality. There are a few different ways to do this:

One option is to download a dedicated MIDI app like MIDI Touch or MIDI BLE Connect. These apps allow your phone to function as a MIDI controller by converting touchscreen presses and gestures into MIDI data.

If you want to connect external MIDI devices like keyboards, you’ll need some additional hardware. Many MIDI keyboards and controllers support Bluetooth MIDI, which allows them to pair wirelessly with your phone. You’ll still need a compatible MIDI app to receive the Bluetooth MIDI data.

For a wired connection, you can use an OTG (On-The-Go) cable to connect your phone’s USB port directly to a MIDI device. This bypasses the need for wireless transmission or a MIDI app.

So in summary, enabling MIDI on your phone requires either downloading a dedicated MIDI app, using Bluetooth MIDI compatible devices, or connecting to MIDI hardware directly via OTG cable.

Using On-Screen Controls

One of the simplest ways to use your phone as a MIDI controller is to take advantage of the touchscreen interface. Much like dedicated MIDI controllers and keyboards, the touchscreen can act as a set of piano keys, drum pads, faders and knobs for triggering notes, drums and adjusting parameters in real-time.

By using MIDI apps designed for this purpose, you can easily turn your phone’s screen into a customizable control surface. The app converts screen touches into MIDI data which is then sent to your synthesizers, DAWs or other gear. This allows you to trigger sounds and manipulate them without any external hardware.

While limited compared to physical controllers, on-screen controls work well for basic playing, programming and input. The convenience of having a MIDI interface already in your pocket makes touchscreen control a handy option for mobile music production and performance (Playtronica).

Connecting External MIDI Devices

One of the main benefits of using your phone for MIDI is the ability to connect external hardware synthesizers, keyboards, drum machines and other devices. This allows you to control external gear wirelessly using MIDI over Bluetooth or via a wired connection using an OTG (On-The-Go) cable.

Bluetooth MIDI adapters like the Yamaha MD-BT01 or Roland UM-ONE Mk2 allow you to connect your phone wirelessly to MIDI devices and instruments. This gives you wireless control and playback without cables getting in the way.

For wired connections, an OTG cable can connect your phone to a synth, MIDI keyboard or other hardware via the USB port. This provides low latency, wired MIDI connectivity. OTG cables are inexpensive and widely available.

Connecting external gear vastly expands the possibilities and allows mobile music making at a pro level. You get the advantages of hardware synthesizers, keyboards and drum machines combined with the interface, effects and sequencing abilities of your phone or tablet.

Latency Considerations

When using a phone for MIDI input, latency can be a concern. Latency refers to the delay between pressing a note on a MIDI controller and hearing the sound produced by the synthesizer or virtual instrument. High latency makes it difficult to play in time and get tight timing. There are a few factors that affect latency when using a phone for MIDI:

Bluetooth and Wi-Fi introduce more latency compared to a wired connection. The wireless signal has to be encoded, transmitted, and decoded, which takes more time. Bluetooth MIDI latency can range from 3-10ms typically, while Wi-Fi MIDI latency is usually around 10-20ms (Source).

You may need to adjust audio buffer and MIDI settings on both the phone and synthesizer app to optimize for low latency. Lower buffer sizes reduce latency but increase risk of audio dropouts. Finding the right balance is important.

Using an OTG (On-The-Go) cable to connect MIDI devices directly via the phone’s USB port results in minimal latency, similar to a direct wired computer connection. OTG bypasses the wireless transmission which helps reduce latency to 1-3ms.

In general, wired connections, lower buffer sizes, less wireless hops, and optimized software settings will provide the lowest possible latency for mobile MIDI input.

Popular MIDI Apps

There are several excellent MIDI apps available for iOS devices that offer different features and user interfaces. Here are some of the most popular and powerful options:

TouchDAW provides a full-featured MIDI controller and sequencer in a customizable interface. It includes piano keys, drums pads, faders, and X/Y pads that can all be MIDI mapped. TouchDAW offers advanced editing capabilities like a step sequencer and arpeggiator.

MIDI Designer Pro allows you create your own custom MIDI controller interfaces with buttons, faders, knobs, and more. It’s optimized for use with virtual instruments like Hauptwerk and GrandOrgue. The app includes ready-made templates for popular hardware MIDI controllers.

Lemur turns your iOS device into a customizable touchscreen MIDI and OSC controller. It provides physics-based objects like sliders, buttons, and balls that can be arranged into advanced control interfaces. Lemur is integrated with popular DAWs and plugins.

An app called MIDI Mockup allows routing MIDI between other apps on your iOS device. This enables creating more complex setups using multiple MIDI apps at the same time.

Creating Custom Control Interfaces

Many smartphone MIDI apps allow you to build custom user interfaces that are tailored to your hardware setup and personal workflow. Apps like Yaeltex, TouchOSC, and Lemur let you design your own on-screen faders, knobs, buttons, and other controls.

With these customizable apps, you can create touch interfaces optimized for your needs. For example, you can design a UI with drum pads for finger drumming, faders for mixing tracks, or transport controls for your DAW. The interface can match the exact layout of your external gear.

Building your own control interface allows your phone MIDI setup to integrate seamlessly into your studio. You can have quick access to the specific parameters you need without extraneous controls getting in the way. Custom UIs also help maximize screen real estate on your mobile device.

For live performance applications, tailored touch interfaces let you focus on playing music without worrying about hitting the wrong control. You can also create different UIs for different parts of a song or preset configurations for different instruments.

Considerations for Live Playing

If you plan to use your phone for MIDI input during live performances, there are some important factors to consider:

You’ll need to securely mount your phone to prevent it from moving around and potentially disconnecting cables or falling. Some options are specialized phone mounts designed for musicians or mic stands with phone holders. Proper cable management is also essential to avoid tripping hazards or cables being pulled out. For charging, consider a backup battery pack in case your phone battery starts to run low during longer gigs. Anker and RAVpower make high capacity battery packs that can provide multiple full phone charges.

According to redditor u/synthguy on r/WeAreTheMusicMakers, “Using a MIDI controller with your phone on stage requires a very solid and secure way of mounting your phone…Any cables should be secured and have enough slack when moving the instrument around.” (source)

Proper planning and setup can allow your phone to be a versatile MIDI input for live performances without technical difficulties. Test your rig thoroughly before playing any important gigs.

Summary

Phones have become versatile and portable options for MIDI input and control. With the right apps and adapters, phones can connect to MIDI devices wirelessly via Bluetooth or wired via USB. This allows you to use the touchscreen and sensors on your phone as MIDI controllers for instruments, DAWs, lighting, and more.

The main advantages of using a phone for MIDI input are portability, customizability, and wireless connectivity. Many MIDI apps allow you to create customizable interfaces with faders, knobs, pads, and more tailored to your needs. This provides flexible control options in a compact device you already have with you.

Latency can be a factor to manage carefully when using phones for live playing of instruments. But latency can be reduced by optimizing app settings, using wired connections, and having capable phone hardware. There are many feature-rich MIDI apps available to choose from from basic utilities to advanced production suites.

With the right setup and knowledge, phones have excellent potential as wireless, portable, and customizable MIDI controllers for music, visuals, and stage performances.