pctechguide.com

  • Home
  • Guides
  • Tutorials
  • Articles
  • Reviews
  • Glossary
  • Contact

Midi Sound Cards

The Musical Instrument Digital Interface, or MIDI, has been around since the early 1980s. It was developed to provide a standard way of interfacing music controllers such as keyboards to sound generators like synthesisers and drum machines. As such, it was originally designed to work via a serial connection and can be viewed in the same light as an ASCII RS-232 link – namely as a combination of an information transfer standard and an electrical signal protocol.

MIDI

On the electrical side, MIDI is a half duplex 5MA current loop, which carries an 8-bit serial data stream at a bit rate of 31.25 kilobaud. The use of a current loop means that two devices talking via MIDI can be electrically isolated using opto-isolators, which is an important factor in ensuring the safe and noise-free operation of a system encompassing both audio and computer-based hardware. This is why a special cable is required to connect a sound card to an external sound generator or MIDI controller, as the opto-isolators and current buffers aren’t included on most sound cards.

On the information side, MIDI is a language for describing musically important real-time events. It communicates over 16 channels (in much the same way that it’s possible to have seven SCSI devices in a chain), allowing up to 16 MIDI instruments to be played from just one interface. Since the majority of sound cards are multi-timbral, 16 instruments can be played simultaneously from just one device. Adding a second MIDI interface opens up another 16 MIDI channels. Some MIDI interfaces offer as many as 16 outputs, making it possible to access 256 at the same time.

MIDI doesn’t actually transmit sound, just very simple messages which the receiving device responds to. Instruments are connected via standard 5-DIN plugs. When a key is pressed on, for example, a keyboard, it sends a Note On message down the MIDI cable instructing the receiving device to play a note. The message consists of three elements:

  • a Status Byte
  • a Note Number
  • a Velocity Value.

The Status Byte contains information about the event type (in this case a Note On) and which channel it is to be sent on (1-16). The Note Number describes the key that was pressed, say middle C, and the Velocity Value indicates the force at which the key was struck. The receiving device will play this note until a Note Off message is received containing the same data.

Depending on what sound is being played, synthesisers will respond differently to velocity. A piano sound, for example, will get louder as the key is struck more firmly. Tonal qualities also change. Professional synthesisers often introduce extra timbres to imitate the sound of the hammers striking the strings.

Continuous Controllers (CCs) are used to control settings such as volume, effects levels and pan (the positioning of sound across a stereo field). Many MIDI devices make it possible to assign internal parameters to a CC: there are 128 to choose from. From those, the MMA (MIDI Manufacturers Association) developed a specification for synthesisers known as General MIDI.

The first MIDI application was to allow keyboard players to layer the sounds produced by several synthesisers. Today, though, it is used mainly for sequencing. – although it has also been adopted by theatrical lighting companies as a convenient way of controlling light shows and projection systems.

Essentially, a sequencer is a digital tape recorder which records and plays MIDI messages rather than audio signals. The first sequencers had very little memory, which limited the amount of information they could store: most were only capable of holding one or two thousand events. As sequencers became more advanced, so did MIDI implementations. Not content with just playing notes over MIDI, manufacturers developed ways to control individual sound parameters and onboard digital effects using Continuous Controllers. The majority of sequencers today are PC-based applications and have the facility to adjust these parameters using graphical sliders. Most have an extensive array of features for editing and fine-tuning performances, so its not necessary to be an expert keyboard player to produce good music.

MIDI hasn’t just affected the way musicians and programmers work; it has also changed the way lighting and sound engineers work. Because almost any electronic device can be made to respond to MIDI in some way or other, the automation of mixing desks and lighting equipment has evolved and MIDI has been widely adopted by theatrical lighting companies as a convenient way of controlling light shows and projection systems. When used with a sequencer, every action from a recording desk can be recorded, edited, and synchronised to music or film. It also provides an economical means for multimedia authors to deliver high quality audio to the listener. The current alternative is to sample the music, but at around 10 MB/min a 40GB hard disk would soon become a necessity. MIDI data requires only a fraction of this.

  • How Do Computers Make Pictures?
  • Graphic Card Resolution
  • Graphic Card Colour Depth
  • Graphic Card Components
  • Graphic Card Memory
  • Graphic Card Driver Software
  • 3d Accelerated Graphic Cards
  • Graphic Card Geometry
  • 3D Rendering
  • FSAA Graphic Card Technology
  • Digital Graphic Cards
  • DVI Graphic Cards
  • HDCP Technology
  • Graphic Card HDMI Ports
  • Graphic Card Display Port
  • Unified Display Special Interest Group
  • DirectX
  • OpenGL technology
  • Direct3D
  • Talisman
  • Fahrenheit Graphic Cards
  • SLI Technology
  • CrossFire Graphic Cards

Filed Under: Sound Cards

Latest Articles

CDR-RW Double Density Media

The idea of a double density writable and rewritable CD media is not new. In the early 1990s a number of companies experimented with extending the White Book and Red Book standards to store large amounts of video. However, these technologies were … [Read More...]

Pentium “Deschutes”

A 333MHz incarnation of the Pentium II, codenamed Deschutes after a river that runs through Oregon, was announced at the start of 1998, with 400MHz and higher clock speeds planned for later in the year. The name Deschutes actually refers to two … [Read More...]

Intel 820 Chipset

Test - Originally scheduled to be available concurrently with the Pentium III processor in the spring of 1999, Intel's much delayed 820 chipset was finally launched in November that year. Those delays - which had left Intel in the position not having a chipset that supported the 133MHz … [Read More...]

Why Cross-Chain Trading Is the Future of Crypto Investing?

The rapid growth and evolution of the cryptocurrency market have opened up exciting opportunities for investors. Within this dynamic landscape, … [Read More...]

Revolutionize Your Internet Experience with Orbi 960 – The Ultimate WiFi System

In a world where seamless connectivity is essential, slow and unreliable internet connections are a major problem. Whether you are running a business, … [Read More...]

Do You Need a VPN When Trading Cryptocurrency?

There’s no doubt that the biggest global industries in 2023 are tech-driven, while there remains a significant crossover between many of these … [Read More...]

Goodbye Bitcoin: the 3 alternative cryptocurrencies that have great upside potential, according to experts

Bitcoin has been a very lucrative investment for people that got into it early. One report from The Motley Fool pointed out that $10 of bitcoin … [Read More...]

Self-driving cars face their Achilles’ heel and may be targets of hackers

The market for self-driving cars is booming. Customers spent $22.22 billion on these autonomous vehicles in 2021 and they will likely spend more in … [Read More...]

How to avoid scams with bitcoin and other cryptocurrencies

Cryptocurrencies got a bad reputation when scams multiplied like ants on a piece of cake. Even today many people associate bitcoin and other … [Read More...]

Guides

  • Computer Communications
  • Mobile Computing
  • PC Components
  • PC Data Storage
  • PC Input-Output
  • PC Multimedia
  • Processors (CPUs)

Recent Posts

Price Slicer Removal

Price Slicer may seem like a useful piece of software you can use to save money while shopping on the Internet. However, it is much more hassle than … [Read More...]

DSTN LCD monitors

A normal passive matrix LCD comprises a number of layers. The first is a sheet of glass coated with metal oxide. The material used is highly … [Read More...]

Copper Interconnect Architecture

Every chip has a base layer of transistors, with layers of wiring stacked above to connect the transistors to each other … [Read More...]

[footer_backtotop]

Copyright © 2023 About | Privacy | Contact Information | Wrtie For Us | Disclaimer | Copyright License | Authors