Ringtones can be sounds in various formats. There are a lot of identified formats specific for the ringtones. One of them is the MIDI ringtone format. MIDI files are complex files often containing thousands of notes, and many channels. This makes a midi file ‘polyphonic’ and to use a midi file on a standard ‘monophonic’ phone we need to simplify it. MIDI is the acronym for Musical Instrument Digital Interface. MIDI was introduced in 1983 as a music industry standard communications protocol that lets MIDI instruments and sequencers talk to each other to play music. The sounds are defined by the hardware instruments used for playback. MIDI files are complex files often containing thousands of notes, and many channels. This makes a midi polyphonic. MIDI (.mid) ringtones are compatible with any phone that supports MIDI. There are many websites out there with premium or free MIDI content. MIDI ringtones help you to identify your phone ringing in a crowd and can be used as message alert tones and as sound effects in mobile phone games. Polyphonic midi tones are downloaded over MMS or WAP or from PC via Bluetooth, infrared or cable.
SP-MIDI – The SP-MIDI (Scalable Polyphony MIDI) specification was co-authored by Nokia Corporation and Beatnik Inc. According to the MIDI Manufacturers Association, “Scalable Polyphony MIDI was conceived as a solution for ‘3G’ (3rd Generation) mobile applications and systems… SP-MIDI provides flexibility to both the system operator and the mobile terminal manufacturer to address differing customer needs. For example, lower-cost phones may be offered that have only 8-note polyphony, vs. higher priced models that have 32-note polyphony, yet the same content will play on either phone.”
Nokia was the first cell phone maker to adopt SP-MIDI followed by Sony Ericsson. The first of these polyphonic phones came out in the second half of 2002. Expect to see this feature in more phones and PDAs in the future.
SP-MIDI is a variation on the general MIDI ringtone format and was designed to allow ringtone composers the ability to compose a single audio file that can be used across a wide range of MIDI-based mobile phones. For example, cheap mass market phones usually have a 4-note polyphonic limit and high-end phone models can have 32-note polyphony. The SP-MIDI ringtones can be used on both 4-note and 32-note mobile phones. SP-MIDI ringtones can be played on the computer with Windows Media Player, but since it’s a ringtone they aren’t the entire song, just a memorable hook or catchy riff from the song.
