Roland MT-32: Многотембральный звуковой модуль

Roland MT 32 Multi Timbre Sound Module

The Roland MT 32 Multi Timbre Sound Module is a MIDI synthesizer module first released in 1987 by Roland Corporation. It was originally marketed to amateur musicians as a budget external synthesizer with an original list price of $695. However, it became more famous along with its compatible modules as an early de facto standard in computer music. Since it was made prior to the release of the General MIDI standard, it uses its own proprietary format for MIDI file playback. 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 monotimbral 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.

Like the Roland D 50 Linear Synthesizer, it uses linear arithmetic synthesis, a form of sample based synthesis combined with subtractive synthesis, to produce its sounds. Samples are used for attacks and drums, while traditional synthesis assures the sustain phase of the sounds. The original MT 32 comes with a preset library of 128 synth and 30 rhythm sounds, playable on 8 melodic channels and one rhythm channel. It also features a digital reverberation effect. 64 of the 128 patches (the limit of possible variations) are completely new or modified sounds, with additional sounds having been added to drum channel 10. Despite this, compatibility with GM is still limited by the lack of parts (9 on the MT 32, 16 per GM specification) and reversed panpot compared to MMA MIDI specifications. The utility was predated by a pack called "MT32GS", released by Mike Cornelius in 1992. The CM Panion, by Gajits Music Software, was an Amiga editor which worked with the MT 32.

Two major revisions of the MT 32 were produced. Roland refers to them as MT 32 (Old / Without headphones) and MT 32 (New / With headphones).

The LA32 sound generation chip is an 80 pin PGA. The control CPU is an Intel C8095 90 in ceramic DIP 48 package. The digital to analog converter (DAC) is a Burr Brown PCM54; the input signal having a resolution of 15 bits (see below). Line outs are unbalanced 1/4″ TS phone connector (separate left and right channels.) No headphone jack. MT 32 with revision 0 PCB, used in units up to serial number 851399. The PGA LA32 chip is later replaced with a 100 pin QFP type. MT 32 with "old type" revision 1 PCB, used in units with serial numbers 851400 950499.

The control CPU is an Intel P8098. Same Digital to analog converter (DAC), but with 16 bits of input signal resolution (see below). A stereo 1/4″ TRS headphones jack is added. MT 32 with "new type" revision 1 PCB, used in units with serial numbers 950500 and up. Roland MT 100: Combination of MT 32 and Roland PR 100 (Sequencer and 2.8" Quick Disk). While it uses a MT 32 (New) PCB, the chassis is different. MT 32 (Old) that have had the mainboard replaced by Roland because of a repair can contain the MT 32 (New) mainboard, with the headphone jack removed.

To target computer users, Roland released a number of CM (Computer Music) modules. They came without an LCD display and had most buttons removed. 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. These sound effects cannot be heard on an MT 32. Early models share a similar design to MT 32 (New). Control CPU is an Intel P8098 and DAC is a Burr Brown PCM54. Roland CM 32L: Released in 1989, this Roland CM has only a volume knob, a MIDI message and a power on indicator as external controls. Roland CM 64: A combination of the CM 32L and the CM 32P, a cut down "computer music" version of the Roland U 110. Like the CM 32P, the CM 64 can be expanded with a Roland SN U110 sound library card (compared to four on the U 110.) The CM 32P part plays on MIDI channels 11 16 which are not used by the CM 32L part. Roland LAPC I: ISA bus expansion card for IBM PCs and compatibles. Includes the MPU 401 interface. In later models, the DAC is a Burr Brown PCM55, and vibrato is noticeably faster. Roland CM 32LN: Sound module for the NEC PC 98 series notebook computers, featuring a special connector for direct connection to the computer's 110 pin expansion port. Released in Japan only. Roland CM 500: A combination of the CM 32LN with the Roland GS compatible Roland CM 300, the "computer music" version of the Roland SC 55. Released around 1992. Roland LAPC N: C Bus expansion card for the NEC PC 98 series of computers. Released in Japan only. Roland RA 50: LA unit with CM 32L ROM (but not all CM 32L samples): Requires software work around or hardware modification to work 100% as a MT 32.

In the period of 1989 to 1993, Robin Whittle of Real World Interfaces 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. by A. Ferndown detailed a mute circuit specially designed for use with the Roland MT 32 module. 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. lt is intended to eliminate the noise that the expander produces after a note off. This noise, which remains audible, becomes pretty irritating after a while when the expander is used at home. For studio use a noise gate is, of course, used".

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. However, some games were designed to exploit errors in earlier units, causing incorrect sound on later revisions. 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 On Line, a leading PC game publisher of the time, took an interest in the sound design of its PC games. 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. King's Quest IV, released in 1988, was the first Sierra title with a complete musical soundtrack scored on the MT 32. The MT 32 with a necessary MPU 401 interface cost $550.00 to purchase from Sierra when it first sold the device. 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. The MT 32 remained popular for musical composition well into the early 1990s, when the game industry began to shift toward CD Audio. For a time, it was described as providing "the most realistic sound available in computer gaming today". 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. Games that played General MIDI tracks on the MT 32 initialized the MT 32's sound bank to approximate the General MIDI Level 1 (GM1) specification, but avoided any of the MT 32's hallmark music synthesis features, adhering to GM1's rather limited set of controllers.

Due to the popularity of the MT 32 as a music playback device for computer games, many modern sound cards provide a simple "MT 32 emulation mode", usually realized by way of a sound mapping comprised either of General MIDI instruments rearranged to roughly represent the MT 32's preset sound bank, or of samples directly recorded from the original unit. 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. Results are often considered poor, as the sampling technology used can not reflect the pitch and time variable characteristics of the original synthesizer technology, and programming of custom sounds (see above) is not being supported at all. One exception is the Orchid SoundWave 32 card released by Orchid Technology in 1994, whose on board digital signal processor (DSP) allowed for a more faithful reproduction of the original sound characteristics. More recently, there have been attempts at emulating the LA synthesizer technology in software using images of the original PCM and control ROMs. The most notable of these emulators is the open source project Munt, which emulates the MT 32 hardware by way of a virtual device driver for Microsoft Windows, or a virtual MIDI device for OS X, BSD and Linux. It is also incorporated into ScummVM, an open source adventure game interpreter, as of version 0.7.0. Munt is based on an earlier MT 32 Emulation Project, which was the source of a short lived legal argument over distribution of the original ROM images with Roland Corporation, who manufactured the MT 32 and claims copyright on the ROM's data. The Raspberry Pi Single board computer has an Open source software emulator called the mt 32 pi. This project allows for Hardware emulation of the mt 32 by use of additional hardware. The project originally started as an emulation solution for the Roland MT 32 synth module, using the open source Munt emulation core. Roland offers emulation of classic synthesizers via the Roland Cloud subscription service. Support for the D 50 was notably added in June 2017.