Belgian Amiga Club - ADF Collection/BS1 part 34.zip/BS1 part 34/FredFish PD 307.adf/DissiDemos/Wrench_Instructions.txt

Text File | 1990-01-13 | 29KB | 488 lines

                       MIDI Sample Wrench Demo
                       dissidents
                       730 Dawes Avenue
                       Utica, NY USA 13502
                       [phone]

Please note: Unlike the commercial versions of dissidents products, this
demo is not set up as a bootable disk. What this means is that BEFORE you
try to run the demos, you must copy certain libraries contained on this
disk to the libs drawer of your boot disk. In particular, you should copy

    music.library
    requester.library
    color.library

Simply put, The Wrench is designed to let you manipulate and alter sounds to
your desire. In short, The Wrench lets you see what your ears hear.
It is to the world of sound, as a desktop publisher is to words
and images. It does not create the sound per se, but rather, allows you to
shape it as required. Of course, with the flexibility and power of its
many functions, the resulting sound may be so altered that it becomes a new
sound in its own right.

Presently, there are a number of MIDI samplers
available to the musician. Generally, they all do a good job of capturing
sound in a digital form, and playing it back. Unfortunately, most of them lack
either a simple user interface or the capability of altering waveform data.
The most basic use of The Wrench is in sending the wave data to the Amiga where
it will be modified, and then sent back to the sampler. In this way, you get
to do things to the sound that the sampler can't do, and, you get to do it
in a very friendly environment. Perhaps just as important is the ability to
crossload sounds. Since The Wrench talks to many different samplers and
stores waves in a common form, it is very easy to send sounds from one
sampler to another.

Let's take a closer look at how some of this is accomplished with an example.
First, start up The Wrench from Workbench. Once The Wrench is up and running,
you should see a light colored blank screen with a title bar at the top.
This is your background work area. It is here where you'll start the three
editors and eventually quit the program. This is also where you make
global settings which effect all three editors such as screen resolution,
colors, and type of wave backups used. When the
background area is active, the mouse pointer will look like an arrow with
tail feathers on it. If you press the right mouse button ( menu button ),
you will see a list of menus. They are Project, Setup, and MIDI. The Project
menu allows you to open each of the three editors, or quit the program.
Don't select anything just yet. Under Setup you'll find the choices Color,
Backups, and Display. Selecting Color brings up the standard dissidents
color window. The Display choice let's you toggle between
200 line ( non-interlaced ) and 400 line ( interlaced ) display.
The Backups item has three sub-items; None, Internal,
and External. These work in conjunction with the editors' Undo feature.
You are going to need the Undo feature, so select Backups/Internal.

Since you would like to view and manipulate a sound, you must call up an
editor. Select Project/Open1 to start up editor number one. A medium size
window with red trim should appear towards the top of the screen. The mouse
pointer will change to a tail-less arrow ( the standard Intuition pointer. )
The other two editors look just like this one except that they are colored orange and
yellow ( these colors help you keep track of menus and such. ) You will note
that the lower and right edge borders contain small push-buttons and
sliders. These allow you to zoom in/out and pan left/right/up/down. The
lower right corner contains a standard window sizing gadget. Select this and
increase the size of the window. Note that the sliders are scaled along with
the window. In the upper left corner you will find the standard window close
gadget. When you are done with this editor, you may close it down by
clicking on this ( but not yet! ) Now hold down the menu button. You should
see a new menu set in the same color as the window ( red. ) The menus are
Sample, Options, Mode, Functions, Markers, and Clips. You would like to load
a wave from disk. Select Sample/Load. The standard dissidents File
Requester appears. Using the Next Disk button, set the disk name
to the SampleWrench disk. The center area lists many of the available files.
You may move through this list with the up/down arrows and scroll bar off to
right. Look for a file called Flute.demo and double click on it. The disk
drive light should come on and a moment later, the edit window will contain
a picture of the wave. The horizontal axis represents time, with the start
of the wave at the extreme left. The vertical axis represents signal
strength. This representation is called a time domain view, and is similar
to what you would see an oscilloscope. Please note that you can still access
the background work area by clicking in it ( obviously, your new edit window
must be less than full size to do this! ) Doing so will change the mouse
pointer and allow you to use the background menus. To Reactivate the edit
window, just click on it.


Now that you have the flute loaded, you can start having some fun. First
off, notice what happens when the window is resized; the wave is scaled to
fit the new window. You can zoom in and out in both the horizontal and
vertical directions by using the four double-arrow buttons. These change
magnification by factors of two. Notice that as you zoom in, the slider knobs
get progressively smaller. The knobs indicate how much of the wave you are
presently looking at. You may also pan left, right, up, or down by using the
single arrow buttons. These will move your viewing position about 10% of the
present view size. Note that when you pan, the position of the slider knob
will change, indicating which part of the wave is presently in view. You may
also pan by dragging the knob to a desired view location. Note that once
you zoom in far enough, the wave will not be drawn in a filled in manner,
but rather, like a single pencil line. When the wave looks like this,
you're ready for micro-surgery!

Sometimes, you'd like to zoom in on a specific area, and the zoom buttons
can be rather cumbersome. For this case, use the Zoom Box mode. Before using
this, make sure that you are not already zoomed all the way in from using the
Zoom In buttons. Simply click on the two Zoom Out buttons a couple of times.
( A very quick way of zooming out completely is to select Sample/Show Full.
Try both of these. ) To enter Zoom Box mode, select Mode/Zoom Box. The mouse
pointer will turn into a small picture of an edit window with a little zoom
box in it. The hot spot for this pointer is the upper left. To use this,
position the pointer near the area that you'd like to take a closer look at.
Hold down the left mouse button and move the mouse over the area of
interest. You should see an outline over the wave. This is
the area that will be shown in the new view. Release the mouse button. In a
moment the new view will be drawn. Before you proceed, return to Normal
mode by selecting Mode/Normal. You now know the basics for moving around in a
wave. This will be very helpful later on when you set loop points, do free
hand drawing, or use any number of functions.



Previewing the Wave


Seeing may be believing, but the ears have final say in matters of sound. It
is possible to use the Amigas internal voices to listen to the wave.
Generally speaking, the quality of this sound will be less than that of the
associated samplers. It is still quite valuable for general use though. To
listen to the flute, first make sure that the audio outputs are connected and
turned up. Select Sample/Play. A small blue requester will appear
in the upper left corner of the edit window. All MIDI Sample Wrench
functions communicate with you in this manner. The requester will allow you
to enter data relevant to that function. Since the internal Amiga voices are
desired, ignore the Remote Channel and Transpose string gadgets, and select
the Local button. In a moment the requester will have disappeared and the
the mouse pointer will have turned into a pair of eighth notes. The Amiga
keyboard can now be used a music keyboard. It is split into two claviers.
The upper clavier uses the Q row as white keys ( Q is A ) and the 1 row as
black keys. The lower clavier uses the Z row as the white keys ( Z is A ),
and the A row as the black keys. The Q key is the standard, or root pitch of
the wave. The lower clavier will extend to one octave below the root pitch.
The upper clavier limit will depend on the sampling rate of the wave. The
maximum upward shift is one octave but it may be less if a high sampling rate
was used. Feel free to play the flute! You will note that you have four
voice polyphony! Also, if you hold down a key, you will notice that the
sound sustains. This particular loop is rather poor, so you'll fix this a
little later as part of the tutorial. To stop the Play mode, just hit the
ESCape key. The mouse pointer will go back to normal. Now that you can
preview sounds, you'll be able to hear the results of your edits
immediately. Sound good so far? Things are only going to get better!



Scale to Full and Undo


Let's dive right into a few functions. One very useful function is called
Scale To Full. This increases the wave to its maximum amplitude. Judicious
use of this function can keep your noise floor at its minimum. Select
Functions/Scale To Full. The Wrench will calculate just how much gain this
wave needs for you, and then apply it. Since no further input is needed from
you, no function requester is displayed. While The Wrench is figuring out
the gain, the mouse pointer will turn into a Thinking sign, indicating that
the editor is busy. Once the calculations are completed, the new wave is
drawn and the mouse pointer is reset. If you'd like, you may preview this
sound by selecting Sample/Play as before. Note that the flute sounds basically
the same, it's simply louder.

If for some reason, you decided that you didn't like the results of this
function, you could get back the previous wave by selecting Sample/Undo.
Do this now. Note that the wave that existed right before the Scale To Full
function was used has reappeared. It's as if the function was never used.
Since you used Internal Backups, the Undo can be undone.
This will return the fully scaled wave. Do this by selecting Sample/Undo
again. Select this one more time to get back the original unscaled wave.



Digital Equalization


One of the more common signal processing functions used in day to day work
is equalization, or EQ, as it is often called.
EQ allows you to change the spectral balance or timbre of a
sound. The Wrench has an extensive digital equalizer. To see the EQ section,
select Functions/EQ. You will note that the EQ requester is rather large and
contains many controls. If your window is too small, part of the requester
may be obscured. If this happens resize the window so that it's a bit
larger.

There are three basic equalizing functions that can be used.
These functions are high/low pass filter, bass/treble shelve, and
parametric EQ. As an example, you are going to add a moderate amount of high
frequency boost to the flute wave. The simplest way to do this is via the
bass/treble shelving control. This control is more flexible than the average bass or
treble control because it allows you to specify the frequency at which EQing
starts to take place. For this example, use 2KHz. You will note that the
Frequency string gadget is already selected and ready to receive input.
Simply type the numbers 2000 into the gadget. ( If the gadget is not
selected, just click on it first, then type in 2000. ) Now, in order to
get a treble control, the Bass/Treble pushbutton must read Treble. Click on
it a few times and notice how it changes from Bass to Treble and back.
Once it is set to Treble, adjust the Cut/Boost slider for a moderate amount
of gain, say 5 or 6 dB. To produce the EQ, click on the Shelve pushbutton at
the bottom of the requester. The requester will disappear and the mouse
pointer will say Thinking as it calculates the new wave. After a moment, the
new equalized wave is drawn. Select Sample/Play in order to hear the new
flute wave. The equalized flute should sound a little brighter than the
original wave, and perhaps a bit breathy as well. ( Note that excessive boost
might cause the wave to become clipped and distorted, just as it would with
a normal equalizer. ) Remember, to exit the Play mode, hit the ESCape key.
The EQ section is very powerful and can alter waves in many ways. The Treble
control is just one function of many. Before you proceed, select
Sample/Undo to get back the original wave.



Markers and looping


If you have worked with samplers for a while, you know the importance of
making good seamless loops. You probably also know the frustration of trying
to achieve those ideal loops! Loops are a necessary evil if you want a sound
to sustain over long periods of time ( several seconds. ) Without loops,
sustaining sounds would require tremendous amounts of memory. A loop is
defined by start and end points within the wave. This section is repeated
for as long as a key is held down. Visual editing is an absolute boon to the
hardcore looper. By seeing what you're trying to loop, the whole process
becomes much easier. Generally, you'll arrive at satisfactory loops in
considerably less time. The trick is to visually determine front and back
parts of the wave which are similar. By doing this, discontinuities in the
loop are minimized, and thus tell-tale clicks and thumps are reduced. Some
waves are easier to loop than others. Very clangorous or harmonically
complex waves can be virtually impossible to loop perfectly. The flute wave
is not particularly difficult.

In order to denote where a loop begins and ends, The Wrench uses Markers.
You have six markers at your disposal. They can be used for purposes other
than looping, but that's all you'll do with them for now. In this section,
you're going to create a new sustain loop for the flute wave since the
default loop was not very good. At this point, you're interested in the
Markers menu. First of all, markers are shown on the wave drawing as
numbered vertical lines ( blue, if using default colors. ) Even numbers are
drawn at the base of the line while odd numbers are drawn at the top. To see
where your markers are, select Markers/Show Markers. You should see one
marker at the front of the wave and one at the rear. Only two markers are
presently in use. They have been pre-defined to indicate the sustain loop.
In order to verify the sustain loop, select Markers/Show Loops. You should
now see a horizontal line at the base of the wave, extending from the
beginning marker to the end marker. Note that this line is the same color as
the markers. Also, note that it is possible to view the loop
without viewing the markers. In this example you'll want to see both, though.
You can verify all of this by selecting Sample/Info. Info will tell you the
exact position of each marker ( in samples ) and also show which markers are
used for the loops. The Wrench can deal with two different loops, a
Sustain loop and a Release loop ( for now, you only care about the Sustain
loop. ) Unused Markers will have no number after them. Note that only
Markers two and four have values. These were set when the wave was initially
loaded from disk. Also note that the Sustain loop is defined
as starting at Marker two and ending at Marker four. ( As you can see, this
requester provides other items of interest including the sampling frequency
and wave size. ) Exit the Info requester by selecting the Okay button ( if
the bottom of the requester is obscured, resize the window larger. )

The reason why the default loop is so lousy is because the markers were
poorly placed ( on purpose! ) Zoom in on the start Marker ( #2 ) by using
either the Zoom Buttons or Zoom Box. Magnify your view until only a few cycles
( repetitions ) of the wave can be seen. Try to memorize the shape of the
wave and pay particular attention to where the marker intersects ( is it
above, on, or below the center line? ) Now, by using the horizontal scroll
slider, move over to the other marker ( #4. ) ( If you can't see the blue
horizontal Sustain line at the bottom of the wave, you've gone too far, so
backup! ) You will notice that the cycles in this section of the wave look a
bit different than in the first part. Also, this Marker is intersecting in a
different area. So, that's two good reasons why the loop sounds so bad!
To fix this, you'll need to pick out similar areas. First, zoom out fully so
that you can see the entire wave again. ( Select Sample/Show Full. ) The
start Marker was placed on the attack portion of the wave. Usually, this is
not a good place to start a loop because the sound has not yet reached full
volume. Fortunately, the end Marker is reasonably placed.

What you would like to do now is reposition the start Marker,
so select Markers/Set Marker/2. A small requester will pop up
with "Set Marker #2" on it. You can position the marker by
either typing in a position from the keyboard, or by
using the mouse. Both techniques have their advantages, but for this
example, select Mouse. After the requester disappears, the mouse pointer
will turn into a placement pointer ( a thin vertical line with end pieces. )
Place this pointer over the wave and press and hold the left mouse button. A
thin, lightly colored line appears under the pointer. While still holding
down the left mouse button, move the pointer over the wave. The line tracks
the mouse position. Its purpose is it to make it a little easier to judge
your position in the wave. A good spot for the marker would be after the
initial attack, somewhat to the right of the first obvious bump ( around one
third of the way through the wave. ) When you get the pointer
to this area, release the mouse button. The wave is redrawn
and the new marker position is shown. The Sustain loop line has also been
adjusted to reflect the change automatically. If you don't like your
position, you can repeat the process be selecting Markers/Set Marker/2
again.

This marker positioning was rather broad. Although you are in the right
area, you don't know if the precise marker intersection is that good.
Usually, markers are set at zero-crossing points on the wave. You would like
to do this. Zoom in on the start Marker until only a few cycles are visible.
Chances are, it will not be on a zero-crossing. You will have to fine-tune
your position. For the sake of convenience, look for a positive going
zero-crossing ( ie a point where the wave intersects the centerline as it
rises. ) Select Markers/Set Marker/2. From the requester, select Mouse, and
position the pointer over this zero-crossing. Press and release the left
mouse button to set the marker. Before proceeding, note the general shape of
the wave in the vicinity of the marker. By using the horizontal scroll
slider, move to the end Marker. You will probably have to reposition this
one a bit as well. Try to find a zero-crossing area that looks like the
one you just did. Select Markers/Set Markers/4, and reposition this marker as
you did the previous one. Once this is accomplished, the loop is done. You
may audition your work by selecting Sample/Play as you did before. If you
made reasonable choices, the loop should be much smoother than the original.
( To exit Play mode, hit ESCape. )

Successful looping is half art and half science. Do not be dismayed if this
first attempt was less than perfect. As time progresses and you become more
comfortable with The Wrench and waves, your looping skill will increase. To
make your life easier, The Wrench offers certain automated looping features,
as well various forms of crossfade looping for those more difficult sounds.
As a side note, even though you only fiddled with markers #2 and #4, any of
the six available markers may be used to define the loop by using
Markers/Set Loops.



Cut, Paste, and Clip


Well, it's time for the last element of the tutorial. Before you start, make
sure that you can see the entire wave ( select Sample/Show Full. ) In this
final section, you shall perform cut and paste operations. This is kind of
like tape editing with a microscopic razor blade! Functionally, it works a
lot like the cut and paste operations found in many word processors. You can
do some pretty neat things with these functions. You can lengthen or shorten
sounds, splice different sounds together, or even rearrange different parts
of a sound. For example, you might sample someone speaking a sentence,
and then alter the order of the words! ( As a gag, you might rearrange your
favorite politicians latest speech and turn it into a pile of meandering,
useless, gibberish. Don't be surprised though, if you can't tell the
difference. )

The basic functions for this section are found under the Clips menu.
Basically, the routine runs something like this: you define a Clip ( a chunk
of the wave ) by using either Markers or the mouse, then you either Cut it
( remove it from the wave ), or Copy it for later use. The copied clip is
placed in a Clipboard which can be accessed from any of the three virtual
editors. From the Clipboard, a clip may be Pasted into a wave ( inserted
into the wave at a desired point. ) The Clipboard will hold up to six clips
at any given time. To help keep things straight, each clip can be given its
own unique name. This is the basic theme. There are a few useful variations
and features besides.

First, you're going to grab a clip from the flute wave. Select Clips/Clip.
A small requester will pop up indicating that The Wrench is ready to work on
Clip #1. You can name each clip, so give this one a meaningful name like
"fido". After you've typed fido into the Name gadget, select the Mouse
pushbutton. Defining clips with the mouse is very quick and easy ( more
exacting applications can use a pair of markers. ) After the requester
disappears, the mouse pointer will turn into the placement pointer. You are
going to grab the last half of the flute wave. To do this, position the
pointer over the middle of the wave. Now, press and hold the left mouse
button. While still holding the mouse button, move the pointer over to the
right edge of the wave. Notice how the intervening area is shown in reverse
highlight. This is the clip. Release the mouse button. You now have a clip
called "fido" in the Clipboard. At this moment, the clip has not actually been
copied to the Clipboard, it is only referenced. To complete the job, select
Clip/Copy. You might wonder why this is a two step process, and why The
Wrench doesn't automatically copy the clip for you the way many word
processors do. Unlike their word processor counterparts, wave clips can be
very large ( several hundred thousand bytes is not unreasonable. )
Unnecessary copying can slow things down and eat up your free memory pool.
Anyway, it would be nice to verify the clip. You can do this by selecting
Clips/Edit. This brings up the Clipboard requester. It shows each of the six
available clips, their names, and their sizes. A little star after the clip
number indicates that the clip has been Copied. Your Clipboard should
contain a single clip called "fido". It should have a star after the 1. You
just wanted to verify this, so return to normal processing by selecting the
Okay pushbutton.

At this point, you could either Cut this clip, or Paste it. Select
Clips/Cut. This will remove the clip and your new truncated wave will be
drawn. Time to try the Paste function. Select Clips/Paste. The Wrench will
need a paste position for this clip. The position may be specified by either
a marker or the mouse. As usual, select the Mouse pushbutton. You will be
greeted with the familiar placement pointer. It works just like the other
placement pointers. Position it where you would like the clip to be
inserted ( just about anywhere is fine for this example ) and press and
release the left mouse button. After a moment of calculation, the wave is
redrawn with the clip inserted. Once the initial clip has been copied into
the Clipboard ( as you've done ), it can be pasted repeatedly ( try this. )
Once you are finished with a clip, you should discard it by selecting
Clips/Erase ( do this and answer Yes at verification. )


The End


To close the edit window, click on the Close gadget in the upper left
corner. Since this operation will forget the contents of the editor, you are
asked for verification. After answering Yes, only the background window
remains. Select Project/Quit to leave The Wrench.



     SOME ITEMS NOT READILY APPARENT WITHOUT THE REAL USER'S MANUAL


1) Two global menu settings are available. These are EDIT ALL and AUTO
ZOOM OUT. They are found under the background Setup menu. If EDIT ALL is
checked, the entire wave will be altered, otherwise, only the area presently in
view will be altered. The following functions are effected: Digital EQ, EG,
Transfer Function, Compressor, Scale To Full, Reverse, DC Offset, Invert, Gain,
and Play. Play does no editing of course, instead, you'll just hear the area
presently in view. If this area is less than the full wave, the sound will be a
'one shot' type. In other words, loops will be ignored.

2) AUTO ZOOM OUT has the effect of showing the entire wave if an edit caused
the wave to change in size. In this way, the overall effect can be clearly
seen. You can turn off this ability if desired. This can be useful if you are
preforming very small edits at high magnifications, where the view position
doesn't change much. This effects the Cut and Paste operations, the Combine and
Append functions, and the Undo feature.

3) Under the Markers menu, a new VIEW MARKER choice is available. By
selecting the desired marker number, the horizontal view position will be
changed so that the marker will be lying roughly mid-window. This is very
useful for setting loop points. Normally, marker-loop adjustment is
performed under high magnification, and it may take a few moves before
the other end of the loop is located. Now, by selecting VIEW MARKER, the
other end of the loop will come into view immediately ( use CTRL-Marker
Number for the keyboard shortcut - upper row only - do not use the numeric
keypad ).

4) Also under the Markers menu is the VIEW LOOP choice. This will cause
the view to adjust so that the overall looping section may be inspected.

5) A FILTER pushbutton is located on the Play Sample requester. This
allows A500 and A2000 owners to set the response of the Amiga's audio
filters. When the button is highlighted, the filter is on, forcing a high
frequency roll off. When the button is not highlighted, the filter is open,
creating a brighter sound. An open filter may produce an increase in alias
distortion, so the setting is a subjective one.

6) Thanks to an update in our requester.library, you can now get a list of
mounted devices from the FileIO window by clicking on the right mouse button.
This can be a bit quicker than using the Next Disk button repeatedly if you
have a large number of devices available.

7) A keyboard shortcut for mouse-based Marker placement exists. You may
bypass the Set Marker requester completely by holding either ALT key and then
hitting the desired Marker number along the upper row of keys ( 1 through
6 ). This will immediately turn the mouse pointer into the insertion pointer.
These shortcuts can speed up the fine tuning of Markers used for loop
definition.

8) There is a keyboard shortcut for pasting clips into editors with the
mouse. This bypasses the Paste Requester. By holding down either ALT key and
then hitting P, you go directly into the mouse paste mode.

9) Since a major part of the editing process involves previewing the sound
with the Play option, we have made access to this feature a little faster.
There are two keyboard commands which will take you directly into either
the Play-Local or Play-Remote options. These are CTRL-L and CTRL-M,
respectively. The last values set in the Play Requester will be used. This
allows you to set the desired values on your first call to the Play
function, and completely bypass the Requester for future calls. Note that
the CTRL-L and CTRL-M calls may be repeatedly used after each other without
having to call up the Play Requester. As this feature is intended to be a
speed-up aid for more experienced users, no menu equivalent is available.
( If you are a confirmed mouse-freak, give the keyboard command equivalents
a good trial period. Most folks report that mouse/menus are very good when a
program is new, but that the keyboard is faster and more productive once you
get used to it. Ever try typing a letter to a friend by just using a mouse? )

10) You can play clips without having to copy them into an editor. By
selecting Play from the Clips menu, the active clip for the present window
will be played back from the Amiga keyboard. The output is in one-shot
mode only. Also, the period used is that of the present wave. If there isn't
a wave in the editor, a default period of 32000 nanoseconds ( 31.25 KHz )
is used.