MIDI Cables: A Guide to Choosing the Right One

What Is MIDI?

MIDI (Musical Instrument Digital Interface) is a protocol for sending musical performance data between devices. Instead of audio, MIDI cables carry digital messages (note numbers, velocities, control changes, etc.). For example, when you press a key on a MIDI keyboard, it sends a message describing that note (pitch, duration, and speed) to the connected device; the receiving device then produces the sound. In short, MIDI cables transmit a digital “score” of data, not the sound itself.

Types of MIDI Cables

There are several types of MIDI cables, each designed for different purposes. Let’s take a look at the most common ones:

Traditional 5-Pin MIDI Cables

• What It Is: A traditional 5-pin MIDI cable connects instruments such as keyboards, synthesizers, and drum machines.
• Why Use It: It transmits MIDI data between devices via a 5-pin connector, but only three pins are used for communication.
• Example: You can use this cable to connect a MIDI keyboard to a sound module or computer.

USB to MIDI Cables

• What It Is: These cables convert MIDI data into USB signals, allowing you to connect MIDI devices to your computer.
• Why Use It: This is a simple and effective solution for directly connecting a MIDI keyboard or controller to a DAW (Digital Audio Workstation).
• Example: Use a USB-A to MIDI cable to connect a MIDI keyboard to a laptop for music production.

USB MIDI Interface Cables

• What It Is: These cables connect multiple MIDI devices to your computer via a USB port.
• Why Use It: If you have multiple MIDI devices, this interface provides a convenient and straightforward solution for managing multiple connections.
• Example: The M-Audio Uno USB MIDI interface connects MIDI keyboards and controllers to your DAW.

MIDI to USB Cables

• What It Is: This cable connects a MIDI device directly to your computer’s USB port, making it easier to connect to your DAW.
• Why Use It: The MIDI to USB cable is designed for direct setups that utilize a MIDI device.
• Example: This cable is perfect if you have a MIDI keyboard and want to connect it to your computer for music production.

TRS to MIDI Cables

• What It Is: These cables transmit MIDI data using a 1/4-inch TRS (Tip-Ring-Sleeve) jack.
• Why Use? They’re great for connecting pedals or MIDI devices in your guitar setup.
• Example: A Rockboard flat TRS to MIDI cable connects a guitar pedalboard to a MIDI controller.

How Does MIDI Work?

MIDI transmits serial data at about 31.25 kbps through the cable. Each MIDI message is a small packet (note-on, note-off, control change, etc.) consisting of a status byte and one or more data bytes. A single MIDI cable can carry up to 16 channels of MIDI simultaneously, allowing you to have multitimbral instruments or layered parts on one cable.

Devices usually have three MIDI ports: OUT (sends data), IN (receives data), and THRU. Data flows from a device’s OUT port through to another’s IN port. A MIDI THRU port copies the incoming data and forwards it, letting you daisy-chain multiple instruments. For example, you might connect keyboard OUT → synth IN, and then that synth’s THRU → next synth’s IN.

Importantly, MIDI was designed with isolation in mind: the MIDI IN utilizes an optical isolator to prevent ground loops and noise. This means each device’s ground is kept separate, avoiding hum when gear is interconnected.

Choosing the Right MIDI Cable

The MIDI cable you need depends on your setup and how you plan to connect your device. Here’s how to make your choice easier:

For the MIDI Keyboard to the Computer

Choose the USB to MIDI cable to connect a MIDI keyboard to your computer. This is an easy way to send MIDs to your music software.

For the MIDI Controller to the Sound Module

The 5-pin MIDI cable connects sound modules or external MIDI controllers. This ensures a stable connection and safer data transfer.

For Multiple MIDI Devices

It’s best to use a USB-to-MIDI cable when connecting multiple MIDI devices. This cable allows you to manage multiple connections through a single USB port.

For Pedalboard Setups

When working with pedalboards, consider using a TRS-to-MIDI cable. These compact cables help minimize clutter while providing the MIDI functionality you need.

FAQs

Conclusion

Choosing the right MIDI cable ensures your instruments and computer stay in sync. Always match the cable type to the ports on your devices: use 5-pin DIN cables for classic MIDI-to-MIDI links, USB cables for USB-MIDI connections, and TRS cables if your gear specifies it. For complex setups, a multiport USB interface or MIDI through box can keep things tidy.

Remember that cable quality and length matter – short, well-shielded cables give the best performance. With the right cables (or wireless/USB alternatives), your MIDI devices will communicate reliably and latency-free, letting you focus on the music, not the connections.

Sam Wu

Sam Wu is the Marketing Manager at Romtronic, holding a degree in Mechatronics. With 12 years of experience in sales within the electronic wiring harness industry, he manages marketing efforts across Europe. An expert in cable assembly, wiring harnesses, and advanced connectivity solutions, Sam simplifies complex technologies, offering clear, actionable advice to help you confidently navigate your electrical projects.