cmcmanis@sun.UUCP (03/24/87)
This is a description of the Mimetics SoundScape software for the Amiga
Version 1.4. For a lot of reasons I think this stuff is great however
since I haven't used anything else I wouldn't know any better anyway :-)
Mimetics sells three packages for the Amiga, they consist of a MIDI
interface (that plugs into the serial connector), an 8 bit stereo
sampler, and the Pro-Midi Studio package. I have been using the
Pro-Midi studio and Sampler software for a couple of weeks now.
------- THE SAMPLER PACKAGE
The sampler is a device that sits on the second joystick/mouse port of the
Amiga and digitizes sounds from either a stereo line level source or a standard
'cassette deck' type microphone. Depending on how much memory you have (I
have 1 Meg) the samples can be anywhere from .1 sec to 4.5 seconds long. When
digitizing new sounds I typically digitize for a couple of seconds and then
use the sound editor to cut out just exactly the portion of the sound I want.
To begin digitizing you select the octave for the new sound, and then click
on sample. The screen blanks (because the entire machine is needed to run the
sampler at 50 Khz through the joystick port) and the program begins digitizing
and playing back the input in real time. This allows you to adjust the input
volume of the source for the maximum dynamic range. When the sound would clip
normally the software adds extra distortion so that it is 'obvious' that you
have reached the limit. This distortion is *not* there when you sample, they
added it as a sort of audible VU meter for sampling. So after hearing the
distortion, you adjust the volume to just under that value then start the
sample by clicking the left mouse button. There is a threshold control that
can delay the start of the sample until a certain signal level is received.
When the sample starts the screen turns yellow indicating that sampling is
in progress and then the SoundScape windows reappear when it is done.
The sample then appears in the editing window.
The editing window has three 'markers' and two 'sliders'. The markers
determine the start point of the sample, the beginning loop point and
the ending loop point. The sliders determine the 'scale' which is sort
of a zoom in factor on the waveform, and a position which determines
where in the wave the editing window is positioned. While editing you
can use the top two rows of the keyboard as a simple musical keyboard to
play back your sample at various pitches. After extracting the exact piece
of sound you want from the original sample you can 'clip' it. This throws
away the data that is outside the start and end-of-loop markers and saves
a bit of space. At this point you can also copy *or* 'transpose' the sample
into different octaves. Copy is fairly obvious, but the transpose option
attempts to maintain the tonal relationships of the various harmonics in
the sample.
After all this you can save the sample out to disk, and pop back into the
'envelope' window. This window lets you adjust what I used to think of as
the VCA envelope. Basically it is a 6 part ADSR envelope. So far I mainly
use it for adding nice decay effects but like I said it has only been a
couple of weeks.
------- THE PRO-MIDI STUDIO
The MIDI studio part of the package is just that, a software MIDI studio.
The primary window of this package is a 'patch panel' where several MIDI
sources and targets appear. Of these, there are a MIDI Connector which
is logically attached to the MIDI port of the Amiga, whatever you patch
this too will receive MIDI events from the External connector. The Clock
which is a standard MIDI timebase generator. This will generate MIDI timing
events that can be connected to the sequencer and to external MIDI devices
for use by any thing that needs time events. A mixer which I haven't used.
A speaker, which simulates a four channel sampled sound box using the four
Amiga sound channels. And the Amiga keyboard which can be set up to generate
MIDI events for the system. Lastly there is the Tape Deck which is simply
an n track, and n note sequencer where n is determined by how much memory
you have. Note Events take up about 10 bytes in the sequencer and tracks
add about 15 bytes per track so on my machine there is space for about
30,000 notes. Any extra memory you add directly translates into note
memory so if I had one of those 2 Meg memory cards I would have room for
an additional 200,000 notes.
The sequencer is a full fledged unit, you can record on any track, quantitize
tracks, cut and paste sections of notes, there is even a 'punch in' and 'punch
out' facility that will activate the record button at a starting timestamp
and deactivate it at an ending timestamp allowing you to rerecord one small
section on an otherwise perfect track. Also the output of the sequencer can
be any one of the patch panel items so you can use it just like a built in
sequencer for your synth. Another nice feature is that you can 'preview'
the tracks with the Amiga playing sampled sounds, and then use it to drive
the ESQ-1 when you go to record. Note that the limits of the Amiga are
4 voices max, but with any timbre, and it can switch timbres between
notes.
This package is already a really useful sampling and sequencing package,
it also gives me capabilities with my DX-100 that weren't previously
available like being able to play sampled voices, splitting the keyboard
and doing polytimbral stuff. However the Mimetics folks have also made
public the format for writing your own modules in C and adding them to
the system. To write a module you simply provide routines for
initialization, handling midi events, and user input. You also provide
an icon for the patch panel. At a recent demonstration of this stuff
Mimetics had Todor Fay, the author, show how easy it was to write
modules. His first one was a simple 'chording' module. This module
consisted of an initialization module and a input routine that took the
note event it received, extracted the note number from the structure,
created two more note events for the third and fifth to make a major
chord and sent them out. When you run your new module, the icon you
have designed appears in the patch panel, when you patch it to other
midi devices the SoundScape system notes who you are talking to so when
you throw out midi events like the chord module above, they get fed to
the inputs of the modules you are patched in to. His second module did
some echo type effects by simply repeating the received midi event 'n'
times where 'n' was settable from a user window. I went home and
modified it to also cut the key velocity by a fractional amount each
time which added a decaying effect.
Do I like it? Sure I do, the 1.4 version is a very robust package unlike
some of it's predecessors. If you get all three parts (The MIDI
interface $50, the Sound sampler $100, and the Pro-Midi Studio package
$150) it goes for about $300. But that was less than a new synth or a
Drum machine, or a sequencer, etc. So personally I considered it a good
deal. What don't I like about it? Well their manual stinks, they claim
to be working on that, I find it unfortunately typical of small software
enterprises. They don't provide enough samples with their package or
any really hot prerecorded sequences. I suspect that the reason is simply
a lack of time and effort. I still reccomend it though.
--
--Chuck McManis
uucp: {anywhere}!sun!cmcmanis BIX: cmcmanis ARPAnet: cmcmanis@sun.com
These opinions are my own and no one elses, but you knew that didn't you.