Making music on the A\Box
by: Alf Inge Wang
at NTNU
Output
The A\Box comes with four 16-bit CD-quality audio
outputs as standard. Who need four audio outputs ? Isn't stereo (two) output
enough ? Most high-cost, high-quality synthesizer have four outputs as
standard. The reason for this is that you have a lot more flexibility when
it comes to mixing sounds when recording (you can control four separated
sounds instead of two) and to make special effects. Another useful feature
is that four outputs makes it possible to produce two stereo outputs at
the same time. This feature can be used to let two players of a game hear
different when playing the same game.
Input
A\Box comes with stereo 16-bit CD-quality audio inputs.
Because this is A\Box standard hardware, there is no need for buying an
additional audio-sampler.
Digital Signal Processor (DSP)
The best part of the A\Box audio system is the built
in DSP (FAME). This co-processor makes it possible to mix any number of
tracks (only limited by memory space available). As an example you can
have separate tracks for every instrument in an orchestra and a possibility
to edit each instrument. You can also play all instrument at once and mix
them together as professional audio engineers do (adjust volume and equalize
each track). All the mixing of tracks is done real-time without use of
the main processor. The DSP can also be used to generate sound effects.
The A\Box is a ideal platform for creating sound studio software, because
of A\Box DSP capacities of real-time mixing, and fast I/O (for hard-disk
recording). The DSP (FAME) is also programmable and have almost unlimited
possibilities.
FM and AM synthesis
It is not only digitalized sound A\Box can produce.
A\Box provides built in FM and AM audio synthesis which makes A\Box a true
synthesizer. By using FM and AM synthesis, there is no need for storing
amounts of data for defining the sound. The sound is defined through parameters
that decide how the audio waves behave. However it is not easy or maybe
possible to create all sounds by using FM and AM synthesis.
Easy to expand
Since the A\Box has a PCI-bus, it is possible to use
almost all audio hardware available on the marked. The limitation is software
support for different audio hardware.
Midi-support
Midi is an acronym for Musical Instrument Digital
Interface and is used to connect e.g. synthesizers to computer or to other
synthesizers. By using a midi-connection between your computer and a synthesizer
you can record what you're playing, save/load sounds, program your synthesizer
from your computer etc. Midi can also be used to synchronize video. There
is no plans for a build-in Midi-interface in A\Box. This don't need to
be a problem, since more and more synthesizer has build-in Midi-interfaces.
This means that you only hook your synthesizer to you serial port. There
also exist a lot of external Midi-interfaces on the marked. I have personally
asked Phase5 to include a Midi-interface, but I haven't received any answer
yet.
General
In general digital samples, FM-synthesized sounds
and envelope-VCO generated tones can be generated, modified, mixed and
output via these freely programmable audio-DMA.
Software
My opinion is that A\Box has a lot of audio power,
but my concern is software. If big audio software companies want to support
A\Box, A\Box will become an audio workstation. If not... (you can't do
much with only audio hardware)