MIDI Interfaces Topics:
» What is a MIDI Interface?
» MIDI Ports
» MIDI In, Out, Thru
» Types of MIDI Cables
» Wireless MIDI
» What To Look For...
When MIDI - short for Musical Instrument Digital Interface - was developed nearly 25 years ago, it resulted in a flood of music technology that continues to deliver new, improved ways of making music. While software synthesizers and DAW programs have replaced many of the hardware devices from the 1980s and 1990s, there is still a need to connect keyboards, control surfaces, and other MIDI gear to each other and to computers. This guide discusses many of the things you need to consider when choosing a MIDI interface. Sweetwater Sales Engineers are highly trained and experienced in the ins and outs of MIDI. Call 1-800-222-4700 with any questions you may have.
What is an MIDI interface?
A MIDI interface is a device that allows MIDI equipment such as keyboards, trigger pads, sound modules, and control surfaces to be connected to each other and to a computer. The simplest interface has just one MIDI In port and one MIDI Out port, which allows 16 channels of MIDI data to flow to and from a connected device. Most current MIDI interfaces are cross-platform and work equally well on Mac or PC.
MIDI interfaces commonly come in 2-, 4-, and 8-port configurations (e.g. 8 in x 8 out). Since each port can transmit 16 channels of MIDI data, an 8-port interface can handle a total of 128 MIDI channels. An 8-port MIDI interface such as the MOTU MIDI Express XT is useful for those who have a number of external sound modules, control surfaces, and keyboards to connect. Other configurations are available, such as the Edirol UM-3EX, with three ports, and the 10-port Digidesign MIDI I/O. Many MIDI interfaces allow for the networking of multiple units if more MIDI I/O is needed. For synchronizing MIDI-equipped standalone recorders, video decks, and DAWs, some interfaces, such as the MOTU MIDI Timepiece AV have the ability to resolve MIDI data to word clock, LTC (Linear Time Code), or video sync.
MIDI In, Out, Thru
The MIDI ports found on MIDI keyboards, interfaces, and other MIDI gear are labeled In, Out, and Thru, in various combinations. Some controllers may only have a MIDI Out, some have MIDI In and Out, while others have all three. The In port is where the instrument receives MIDI data from a computer or other device, while MIDI Out is where data is transmitted from the device. MIDI Thru is a useful connection that passes an exact copy of the data present at the MIDI In of the device. This makes it easy to daisy-chain a number of MIDI instruments together so, for example, several hardware MIDI synths can play the same notes or chords simultaneously to create a huge, multilayered sound.
Types of MIDI Cables
The most common type of MIDI cable is 5-pin DIN, otherwise known as a standard MIDI cable. DIN is an acronym for Deutsche Industrie Normung, a German organization that establishes standards for with circular multi-pin plugs, like those found on the ends of MIDI cables. There are also cables used to network multiple MIDI interfaces together such as the mini-DIN 8 Serial cable or the 9-pin "D" for ADAT sync. Many MIDI interfaces now connect to a computer via a USB cable. The commonly used USB cable format is the USB A/B, which has a flat rectangular connector at one end (for the computer) and a square connector at the other (to the unit). Again, most manufacturers supply this cable with the unit.
A recent development in MIDI interfaces, a wireless MIDI interface, such as the CME WIDI-X8 can actually send MIDI information via radio transmitter, just as a wireless microphone transmits voice. The advantage of wireless is a cleaner desktop setup, and the ability to change setups without having to rewire. The WIDI-X8 can also transmit USB via RF, which allows you to connect two computers together. This is particularly handy if you are using one computer for sequencing (recording or live playback) and one for virtual instruments such as TASCAM's Gigastudio.
In order to choose an appropriate MIDI interface for your present and future needs, here are some questions you'll need to ask. Naturally, if you need help answering them, your Sweetwater Sales Engineer is just a phone call away.
Do you really need a MIDI interface?
Some MIDI keyboard controllers now come with a MIDI interface built-in so if you plan on a simple setup and don't have a keyboard controller yet, MIDI controllers such as CME VX Series may be the perfect solution. In addition, many audio interfaces include MIDI interfaces, which means that MIDI data can travel to your computer via the audio interface's USB or FireWire cable.
How many ports will you need?
What are you connecting? The amount of MIDI gear you have determines this. If have just one keyboard controller that you'll be using with a virtual synth setup in a laptop, a simple 1 x 1 MIDI interface will do. However, if that virtual synth is GigaStudio or Kontakt 2 used in standalone mode, you'll need a 4-port MIDI interface - one port for each of their four 16-channel layers. If you are using external MIDI synths, MIDI controller and control surfaces, you'll need at least an 8-port system with the possibility of networking more.
What features do you need?
If all you plan to do is sequence (compose) or perform, then a straightforward, expandable MIDI interface is all you need. A good example is the 5-port MOTU micro lite. If you plan on working with video, or dedicated digital multitrack recorders, you will need an interface that offers video sync options, as well as word clock, ADAT sync, and possibly Superclock (a specification used by Digidesign for Pro Tools). An interface that can be powered via USB (bus-powered) is a great option for mobile setups, since it does not require an additional AC power cable.
Wired or Wireless
Ultimately, this is a matter of choice, but if you're building a project or bedroom MIDI studio or composer's suite with rackmounted gear, a wired system is probably a better choice in terms of gear placement options and stability. Wireless requires line-of-sight access with no obstructions between transmitter and receiver. For live performance, a wireless MIDI interface will offer cleaner setup and mobility. The same holds true for a bedroom/project studio where you may have computer in one location but wish to have a cleaner desktop or the ability to move about the room.
USB 1.1 or USB 2.0?
Make sure you check your computer's USB specification to see if it supports USB 1.1 or 2.0. Many combination audio/MIDI interfaces such as the E-MU 0404 USB employ a USB 2.0 connection.