Music & MIDI
I guess you have discovered that most of the MIDI files you have played doesn't sound nearly as good as MP3s or music CDs. But do you know that many of the music we hear today are produced in studios using MIDI?
MIDI is a standard in the industry and defines, among other things, how musical instruments communicate with each other, and also how the music is stored inside MIDI files.
MIDI does not standardize on the hardware that is used to play back the MIDI files. Nor does it specify the quality of the sound and instruments generated by the MIDI synthesizer. This has resulted in MIDI files sounding bad on many sound cards.
Now let's take a look at the common techniques used to generate MIDI music.
FM Synthesis
In the older days, most of the music synthesizer portion of a sound card used FM or similar techniques. The most common was the Yamaha OPL3 chipset. Music produced by FM are often described as unrealistic and metallic because it uses mathemical algorithms to approximate the sounds of musical instruments.
Wavetable Synthesis
Newer sound cards today make use of a more advanced technique
called wavetable synthesis. Instead of using mathematical algorithms to approximate the sound of musical instruments, actual recordings of real instruments are made and stored in the ROM. These recordings are known as samples.
In earlier sound cards, especially with ISA cards, the sounds are stored in a ROM chip on the sound card. However, with the higher bandwidth of the PCI bus, the newer PCI sound cards are able to forgo the more expensive option of storing samples in ROM. Instead, samples are stored in a file on the hard drive and loaded into the PC's memory as needed. Creative calls this feature PCI wave-table synthesis.
The Sound Blaster Live! uses wavetable synthesis to reproduce instrument sounds, and samples-in-files are called SoundFonts! The EMU10K1 takes on the task. The SoundFonts are stored in the main memory of the PC and played back by grabbing the instrument samples through the PCI bus.
The Sound Blaster Live! has two synthesizers - a hardware synthesizer incorporated in the EMU10K1, as well as a software synthesizer built into the drivers.
A hardware synthesizer does not rely on the CPU to playback MIDI, while a software synthesizer uses CPU time to do so. The hardware synthesizer would definitely perform better with higher sound quality and features (for example, filters and adding of effects). The software synthesizer, relying only on a general purpose CPU, will be bogged down if it were to perform complex sound processing. A specialized sound processor like the EMU10K1 would handle these tasks with ease.
Voices
The number of voices specifies how many instruments can be played at the same time. To play a piece of music, the synthesizer has to generate many tones at the same time. Even on a song with only one instrument, say the piano, more than one key can be pressed at any time, and each of the sound produced by each key will take up one voice.
The hardware synthesizer in the EMU10K1 provides 64 voices, while the software synthesizer provides another 1024 voices (Live!Ware 2 and above). The number of voices supported by the software can be changed.
In Control Panel, click the System icon, click the Device Manager tab, and search for a Creative SB Live! device. Double click on it and select the Synth Options tab. You will see this dialog box:
You can select from 64, 128, 256, 512 and 1024 voices but take note that more voices will result in more CPU time needed to sustain that number of voices.
Practically, most MIDI files do not need more than 64 voices. In fact, many never hit 32 voices! I think being able to handle 1024 voices, or even 256 voices for that matter, is overkill for a software synthesizer. Sounds more like marketing to me!
MIDI Devices
To be able to play MIDI files, the synthesizer must represent itself as a MIDI device in Windows. To see all the MIDI devices available in your PC, go to Control Panel, click on the Multimedia icon, then click the MIDI tab.
The EMU10K1 hardware synthesizer is available as two devices, named as A: SB Live! MIDI Synth and B: SB Live! MIDI Synth.
The software synthesizer is represented as a single device named Creative S/W Synth.
MIDI Channels
Each MIDI device supports 16 MIDI channels. At the channel level, the composer will be able to set the instrument to use in each channel, and control various parameters like the level of effects applied to the instrument, the volume of the channel and many others.
Since there are 2 hardware MIDI devices and 1 software MIDI device, it makes a total of 48 MIDI channels, as stated in Creative's specifications.
MIDI Input & Output
The industry standard MPU-401 UART is built into the SBLive! to provide a MIDI input and output. This is available in the joystick port (using an adaptor), as well as the digital I/O cards and the Live!Drive.
In addition to the 48 MIDI channels built into the SBLive!, you can have another 16 MIDI channels by connecting an external MIDI device to the MIDI output.
MIDI Effects
The SBLive! can handle 2 effects (the standard reverb and chorus) for MIDI. Nothing much is seen in the provision of additional effects and routing features in the drivers, even though the EMU10K1 is a very capable effects processor. What a waste!
If you would like to use the power of the EMU10K1 in a professional application, you may want to consider EMU's APS (Audio Production Studio) which also uses the EMU10K1 but comes with hardware and software drivers
that are geared towards desktop musicians.
For those of us who wish to stick to the SBLive! because of its affordability, EMU will allow their APS 2.0 drivers (and above) to work with SBLive! cards.
Check the musician section for more information on MIDI and Music on the Sound Blaster Live!
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