Within Roland's family of linear arithmetic (LA) synthesizers, the multitimbral MT-32 series constitutes the budget prosumer line for computer music at home, the multitimbral D-5, D-10, D-20 and D-110 models constitute the professional line for general studio use, and the high-end bitimbral D-50 and D-550 models are for sophisticated multi-track studio work.
It was the first product in Roland's Myuujikun (ミュージくん) line of Desktop Music System (DTM) packages in Japan.
Additionally, in 1993 Roland released the "GM2MT" SysEx pack, which can be used to reprogram the MT-32 and compatibles to match General MIDI specifications as closely as possible.
Most of these CM modules aside from the CM-32P and CM-300 are compatible with the MT-32 but feature 33 additional sound effect samples which many games took advantage of.
However, an aftermarket modification was available from Real World Interfaces to improve the MT-32's sound quality and generally increase its suitability for professional use.
In order to improve the signal-to-noise ratio without investing in higher-quality components, the volume of the digital signal fed into the DAC is doubled by shifting all 15 non-sign-carrying data bits to the left, which amounts to multiplying the amplitude by two while keeping the noise floor constant at the analogue output.
However, since the DAC's least significant bit is connected and does change with the sign, the sound quality is improved slightly over the earlier implementation.
In the period of 1989 to 1993,[9] Robin Whittle of Real World Interfaces[10] offered aftermarket modifications to the MT-32 to address its sound quality issues, as well as improve the functionality of the reverberation unit, provide discrete analog outputs for the internal reverb send and reverb return, and provide battery backup of the MT-32's settings.
In particular the changes to the reverb unit functionality will likely cause an RWI modified MT-32 to render reverberation differently from what was intended, with possibly detrimental effects.
Article abstract mentions "The mute circuit presented here Is specially designed for use with the Roland MT-32 module, although with some small alterations it should be suitable for use with other makes of expander er synthesizer.
First generation units, having control ROM versions below 2.00, require a 40 millisecond delay between system exclusive messages.
Some computer games which were programmed to work with the compatible modules (see above) or later ROM versions that do not require this delay, fail to work with these units, producing incorrect sounds or causing the firmware to lock up due to a buffer overflow bug, requiring turning the unit off and on.
Also, some games were written to use instruments not found in the MT-32 models, and require a compatible module, such as a CM-32L, for proper sound playback.
Despite its original purpose as a companion to other professional MIDI equipment, the MT-32 became one of several de facto standards for PC computer game publishers.
Sierra secured a distribution deal to sell the MT-32 in the US, and invested heavily in giving its game titles (at the time) state-of-the-art sound by hiring professional composers to write in-game music.
Although the MT-32's high price prevented it from dominating the end-user market of players, other PC publishers quickly followed Sierra's lead, expanding the role of music in their own game titles with Roland supporting the industry by releasing CM modules for computer users.
[12] The proliferation of the General MIDI standard, along with competition from less expensive "wavetable" sample-based soundcards, led to the decline of musical soundtracks using the MT-32's proprietary features.
Later modules like most of the Roland Sound Canvas series, Yamaha MU-series and the Kawai GMega feature such limited MT-32 backwards compatibility modes.
[citation needed] More recently, there have been attempts at emulating the LA synthesizer technology in software using images of the original PCM and control ROMs.