AmbiLoop 1.40 - September 23rd, 2002

Contents:
	Welcome
	What is AmbiLoop?
	How Does it Work?
	Features
	Using AmbiLoop
	License

Welcome: 
Thanks for your interest in this fourth major release of the AmbiLoop 
software.  AmbiLoop may be downloaded and used free of charge, subject to 
the license agreement shown on the download web page and at the end of 
this document.  We hope you enjoy the program and welcome comments, 
questions and bug reports related to it.  

Chris MacDonald & Chris Roberts
AmbiLoop@yahoo.com


What is AmbiLoop?  
AmbiLoop is a Windows software application that uses your sound card to 
implement a real-time, multi-tracking audio looping recorder.

 
How Does it Work?
AmbiLoop basically functions like a multi-track endless audio tape loop or 
digital delay box with feedback.  Simply set the desired loop time for a 
track and press the record button.  Incoming audio is recorded in real 
time for the length of the loop.  Recording continues seamlessly as the 
loop repeats and the previously recorded audio begins playing back at a 
volume set by the feedback control.  Or just grab a single loop on the fly 
with the Insert Record feature.  AmbiLoop will play up to eight tracks 
simultaneously.  Loops can be slowed to half speed or played backwards,
and a multimode filter and reverb algorithm are available for non-destructive, 
realtime effects processing.


Features:
 (New to Version 1.40)
 * MIDI Control allows nearly all AmbiLoop commands to be triggered via MIDI.
 * Session load/save remembers loop and effect settings unique to your projects.
 * Configuration load/save allows customization of global system settings.
 * Mix-to-track allows real-time mixdown of up to seven tracks to an eighth track.
 * Reverb effect.
 * Pan slider allows panning of mono and stereo tracks.
 * Metronome improved with count-off and auto-mute features.


 (New to Version 1.32)
 * Windows size properly with large system font
 * small application icon corrected

 (New to Version 1.30)
 * Updated track interface.
 * Solo button per-track.
 * Slow and Reverse now selectable per-track.
 * Mute per-track.
 * Insert Record mode to automatically record
   a single, complete pass through a loop.
 * Set loop time via tempo and measures.
 * Change loop time for all tracks simultaneously.
 * Metronome available in play and/or record.
 * Option to use spacebar for Record instead of Play/Pause.
 
 (New to Version 1.20)
 * Play up to eight loops simultaneously.
 * Record and play loops in mono or stereo.
 * Stereo state variable filter with Low/Band/High/Notch outputs plus LFO.
 * Record and playback in reverse.
 
 (New to Version 1.10)
 * Improved user interface.
 * Undo last recording.
 * Half speed recording & playback.
 * Keyboard shortcuts for transport controls.
 * Monitor latent input.

 (new to Version 1.01) 
 * Stereo loop recording and playback. 
 * Seamless recording through loop end-to-beginning transition. 
 * Loop times up to 100 seconds or more (memory limited). 
 * Set loop point while recording. 
 * Instant multiply doubles loop length. 
 * Load and save loops as .wav files. 
 * Multiple sample rates supported (depends on audio card). 
 * Input and output device selection. 
 * Adjustable latency time. 
 * Uses PortAudio library technology (thank you PortAudio group!). 
 

Using AmbiLoop:

SETTING INPUT: You will be recording audio that is sent to the input 
(usually "line" or "mic") of the selected sound card.  See your sound card 
documentation for information on how to select which input will be used.  
Use the Windows volume control application to set the input monitoring 
level.  If everything is working properly you should see AmbiLoop's Input 
Meter flickering as you make sounds.  Be careful not to overload the input 
of your card, as audible distortion can occur.  Avoid extreme or prolonged 
over-driving of the sound card.  Consult your soundcard documentation for 
correct operation of your card.  

SETTING LOOP TIME: You may set a loop time by choosing the 
Options->Set_Loop_Time menu option.  To enter the desired loop time in 
seconds, click on the Seconds "radio button" and enter a value (the Tempo
value will be recalculated based on the new time and the current Measures
value.)  Or, select the Tempo radio button and enter a value for tempo and
measures (the loop time will be automatically computed, 4/4 time is assumed).
If you wish to change the loop time of all the tracks to the new value, check 
the "Set All Loops to This Time" box.  To change the time of empty 
(unrecorded) loops only, check the box marked "Set Empty Loops to This Time."
Click Okay to change the loop times.  

RECORDING A LOOP: Press the Record button on the Transport control and 
begin your performance.  The Loop Position indicator will advance, showing 
where you are in the loop (numbers below the bar show time in seconds).  
Your performance is being recorded, and when the loop completes the Loop 
Position indicator will reset and whatever you played during the first 
pass through the loop will begin playing back.  

You are still recording at this point and may continue to play over what 
was previously recorded.  If you want to stop the loop, press the Stop 
button on the Transport.  To play back without recording, press the Play 
button.  To pause the loop at its current position, press Pause.  Press 
the Record or Play buttons to resume after Pausing.  

SETTING THE FEEDBACK AMOUNT: As you continue recording the sound will 
gradually die out at a rate specified by the Feedback slider.  If the 
slider is set to 0, no recorded sound will be heard during recording.  If 
it is set to 50, the recorded sound will become half as loud on each pass 
through the loop.  If the slider is set to 100, the recorded sound never 
gets quieter.  Be careful at high feedback settings, it's easy to "pile 
up" so much sound on top of itself that distortion occurs.  The feedback 
slider has no effect during playback, only recording.  

SETTING THE LOOP POINT: If you begin recording and decide that you want 
the loop to end before the full loop time has passed, press the Record 
button again, or press the Set Loop button.  This will cause the loop to 
recycle immediately and the loop length will be set to the position at the 
time the button was pressed.  This only works during the first recording 
pass through the loop.  After the loop has recycled once the feature is 
disabled.  If you Erase the current loop, the feature will be enabled 
again for the first pass of recording.  

FROM RECORD TO PLAY WITHOUT STOPPING: If you are recording and want to 
switch to the play mode without stopping the loop, press the Record button 
a second time.  (This only works after the first pass through the loop has 
completed, otherwise you will be setting the loop point as described in 
the paragraph above.)

INSERT RECORDING: This feature can be used to record a loop exactly once 
from beginning to end.  If you press the Insert button while playback is 
under way, the insert light will begin to flash green, indicating it is 
"armed".  The insert light will switch to red and recording will begin as 
soon as the recording track wraps back to the beginning of its loop.  
Recording will continue until one pass through the loop has been made, 
then the insert will end and playback will continue without further 
recording.  If the Insert button is pressed when playback is stopped (Stop 
light is lit), the Insert light will turn red and recording will begin 
immediately.  One pass through the loop will be recorded and then the 
transport will switch to the Play mode.

MIX-TO-TRACK RECORDING:  The Mix To Track feature allows a loop to be
recorded which will contain the sound from any other loops that are
playing when recording takes place.  This allows up to seven tracks to
be mixed down onto one track.  To use this feature, select the "Rec"
button of the track on which you would like to record.  Then select the
"Mix To Track" check box located to the right of the Reverse button in
the Transport Controls area.  When the Record button is pressed, any
loops that are set to play back will be recorded onto the recording track.
You can change volume, pan, and effect settings during recording and
these changes will be audible on the recorded track.  The recorded track
is an ordinary AmbiLoop loop, and may be any length (i.e. not necessarily
the same length as the loops that are playing back.)

MULTIPLYING A LOOP: If you have recorded a short loop but now want to 
record a longer passage over it, press the Multiply button.  This will 
double the loop length and copy the old loop contents twice, seamlessly 
multiplying the loop by two.  Now you can continue recording over the new, 
longer loop.  This feature works at any time.  

USING MULTIPLE TRACKS: There are eight "tracks" available on which to 
record loops.  By default you will record on Track 1.  To select a 
different track for recording, simply click the Record "radio button" for 
the corresponding track in the Track section at the top of the AmbiLoop 
window.  You can now record on the new track and any recording you did on 
Track 1 will remain untouched.  You can move from track to track in this 
way, recording wherever you wish.  The loop transport controls, feedback 
slider, and large loop position indicator will all refer to the track you 
on which are currently recording.  

MUTING A TRACK: If you don't want to hear a particular track, check its 
Mute box.  Note that the current recording track must be unmuted or 
no sound will be recorded.

SOLOING A TRACK: Click on a track's Solo box to silence all other tracks 
and hear the soloed track alone.  You can solo multiple tracks at once.  
Solo even works on a muted track.  Be sure to uncheck all the solo boxes 
when you are done.  If you can't figure out why a particular track isn't 
playing, make sure that other tracks aren't being soloed.  

SETTING TRACK VOLUME: To change the playback volume of a track, move the 
track's vertical slider up and down.  The meter just to the left of the 
slider will show the track's current "post fader" volume.

SETTING TRACK PAN: To change the position of a track in the stereo field,
move the horizontal pan slider (located below the Reverse checkbox) left
or right.  There is a "detent" at the center position so it is easy to
re-center sounds.

TRACK LOOP POSITION: The horizontal meter located above the track volume
control indicates that track's current loop position.  

SAVING LOOPS: To save your loops to disk, choose the File->Save_Loop menu 
option.  A dialog box will appear asking which of the eight tracks you 
would like to save.  Select a track and click Okay.  A file requester will 
appear allowing you to save your loop as a wave file.  A warning will be
displayed if there are unsaved loops when quitting via the File menu, or if
a session save is attempted while unsaved loops exist.  This warning can
be disabled in the Preferences dialog.

LOADING LOOPS: You can also load wave files into AmbiLoop and play them as 
loops.  Select the File->Load_Loop menu option.  A dialog appears which 
allows you to specify the track on which you would like the loop loaded.  
Select a track and click okay.  A file requester will appear allowing you 
to find and load your file.  

SAVING SESSIONS:  A "session" file in AmbiLoop is a file that remembers
what loops are currently loaded, what track and effect settings are 
currently set, and the current tempo and measures.  To save a session, 
select the File->Save_Session menu option.  You can then enter a name and
location for your session file.  Note that loop data is not stored in the
session file, only the location on disk where the loops can be found.

LOADING SESSIONS: Select the File->Load_Session menu option to load a
previously saved session file.  If loop files were moved after the session 
file was saved, a requester will appear prompting for the new loop file
locations.  The session file must then be saved to record the new loop
file locations.

SAVING CONFIGURATION: The configuration file records the current settings
for latency, metronome, preferences, and devices.  It also records the
current "session" information, such as loops loaded and track and effect
settings.  This information is stored in two files, SysConfig.xml and
Default.session, located in the AmbiLoop directory.  These settings will
be automatically restored every time AmbiLoop is started.  To save the
configuration, select the File->Save_Configuration_as_Default menu option.

LOADING CONFIGURATION: The default configuration file is automatically 
loaded when AmbiLoop starts up.  To re-load the configuration file, select
the File->Load_Default_Configuration menu option.

REVERSE FEATURE: Select the Reverse checkbox for any track you would like 
to be reversed.  The Reverse transport button causes playback direction to 
change for all selected loops.  Press reverse to hear your loops 
backwards!  If you have checked the Reverse box for the current recording 
track, you can record a loop while in reverse, then press Reverse again to 
hear the new loop backwards while previously recorded loops play forwards.  

UNDO FEATURE: It is possible to undo the last recorded layer of a loop by 
pressing the Undo button any time.  There is only one layer of undo, so 
every time you press the record button, any previous recording is 
"commited" to the loop.  If your system is tight on memory, try disabling 
the Undo feature in the Options->Preferences menu.  The next time you set 
a new loop time or load a loop from disk, less memory will be needed for 
the loop.  

SLOW FEATURE: Select the Slow checkbox for any track you would like to be 
slowed.  Press the transport Slow button to hear those loops at half 
speed.  If you have checked the Slow box for the current recording track, 
you can now record at half speed as well.  Pressing the Slow button again 
will return the selected loops to normal speed.  Anything recorded at half 
speed will now sound twice as fast and the pitch will be doubled.  

METRONOME: Access the metronome features dialog box by selecting 
Options->Metronome from the menu.  Check the "Audible on Record" box to 
enable the metronome sound to be heard during recording.  Check the 
"Audible on Playback" box to hear the metronome during playback.  Or check 
both if desired.  The metronome volume may be adjusted with the volume 
slider.  The metronome tempo is set to the last Tempo value entered in the 
Set Loop Time dialog box (Options->Set_Loop_Time from the menu).  The
metronome has a count-off feature which causes metronome clicks to play
for a set number of measures before recording actually begins.  To use
this feature, click the "Count Off n Measures" box and enter the number
of measures of count-off desired.  When the Record button is pressed, the
metronome clicks will sound for that many measures before recording begins.
There is also an auto-mute feature, which causes the metronome to go
silent after a set number of measures.  Click the "Mute After n Measures"
check box to enable this feature, then enter the desired number of measures
for the metronome to sound before muting.  Count-off measures are included
in this total.  Pressing Stop resets the mute measure counting.

KEYBOARD SHORTCUTS: There are several keyboard shortcuts available for 
the transport controls: 

spacebar = Stop/Play (or Record via "Spacebar Record" preference)
return = Stop/Play
r = Record/Set Loop Point/Play
p = Pause
v = Reverse
s = Slow
l = Set Loop Point
E = Erase Loop (uppercase E only, a small safeguard)
m = Multiply
u = Undo
i = Insert Record

If you wish to use the spacebar to trigger recording rather than 
play/pause, click the "Spacebar Record" checkbox in the Preferences dialog 
box (Options->Preferences from the menu).  

MIDI CONTROL: Nearly all AmbiLoop commands may be triggered via MIDI.  To
access this feature, select the Options->MIDI_Control menu option.  This
brings up the MIDI Control dialog box.  Although the dialog contols may
seem complicated at first, the operation is fairly simple.  The goal of
the dialog is to match up a MIDI command (called a "MIDI Trigger") with an
action in the AmbiLoop software (called an "AmbiLoop Event").  After this
mapping is made, any time the MIDI Trigger is received, the corresponding
AmbiLoop Event will occur.  To create a new mapping, click the New button
in the lower left corner of the dialog.  This will create a default trigger
and map it to a default event.  Now select the desired MIDI command and
other parameters in the MIDI Trigger list boxes in the upper right of the
dialog.  AmbiLoop is also "listening" for MIDI commands at this point and
will automatically set the MIDI Trigger information to correspond to any
supported incoming MIDI command.  Once you have set your MIDI trigger, 
select the AmbiLoop event you would like this trigger to control.  When 
you are done editing, click the OK button to save your changes to disk, 
or Cancel to abandon your changes.

USING THE FILTER: AmbiLoop features a modeled state variable filter that 
you can use to filter your loops during playback.  The actual contents of 
the loops are unchanged, only the playback sound is affected.  To use the 
filter, click the Enable box in the filter section.  Then click the Effects 
box for the particular track you would like filtered (you can filter as 
many of the tracks as you wish).  Select the Low radio button in the 
filter section.  Now press Play and try moving the Frequency slider to the 
left.  The loop sound will become more muffled until it finally 
disappears.  Move the Resonance slider up to 50% and try moving the 
Frequency slider back to the right.  You will hear a resonant filter sweep 
of your loop.  If you wish to filter the left and right channels 
independantly, uncheck the Link box in the filter section.  You can now 
move the Frequency and Resonance sliders individually.  Filtering is 
non-destructive; your original loops are unaffected by the filtering.  

USING THE FILTER LFO: The filter features a dual Low Frequency Oscillator 
that can be used to automatically sweep the filter frequency.  To use the 
LFO, check the Enable box in the LFO section.  Set the Rate slider to 
around 1Hz and the Depth slider to 100%.  With a filtered loop playing, 
you will hear the filter frequency rising and falling at a rate of one 
cycle per second.  If you wish to modulate frequency of each filter 
independantly, uncheck the Link box in the LFO section.  Now you can move 
the sliders individually.

REVERB EFFECT:  The Reverb effect is located after the filter in the effects
"chain".  To enable Reverb, click the Enable box in the Reverb controls area.
The Length slider controls reverb time.  The Mix slider controls the ratio
of dry sound to reverbed sound.  The Damping slider controls the high
frequency rolloff of the reverb sound.

MONITORING SOFTWARE INPUT: It is possible to monitor AmbiLoop's "latent" 
input (input after it has arrived for processing by the software).  Check 
the box in the Options->Preferences dialog to do so.  Note that this audio 
will be delayed somewhat, in proportion to system speed and other factors.  
For general usage, it may be better to listen to the "real time" input 
sound via the Windows mixer.  AmbiLoop's latency compensation is designed 
to work with the real time input rather than the latent input.  If you 
have a very fast system you may not notice much difference though.  

SETTING LATENCY (CLICKING AND POPPING): If you experience periodic 
clicking or popping while playing loops, you may need to increase the 
latency time.  The default value is 70 which should be sufficiently large 
for most computers.  Finding the right value is a matter of 
experimentation.  To set latency, choose the Options->Set_Latency menu 
option, enter a value (units are in milliseconds) and click okay.  Try 
increasing the value by 10 or 20 until the clicking is eliminated.  
Conversly if you have a fast system, you may be able to reduce the latency 
amount.  AmbiLoop has a latency compensation mechanism so that newly 
recorded sound will match up with playback sound.  This should greatly 
reduce any noticable effects of latency.  Monitoring the latent input 
(described below) may help to more rapidly set a latency value as it 
allows you to immediately hear the effects of the latency time setting 
without needing to record a loop.  

SELECTING AUDIO DEVICES AND SAMPLE RATE: AmbiLoop will automatically 
select an audio input and output device (sound card) upon startup.  If you 
have multiple sound cards or otherwise need to change devices, choose the 
Options->Select_Audio_Device menu option.  A dialog box will be displayed 
with the available input and output devices.  Clicking on a device will
cause its properties to be displayed below the selection box.  The sample rate
at which AmbiLoop records can also be set in this dialog box by clicking on
one of the rates shown.  Click Okay to save your changes.  


License: 
AmbiLoop 1.xx may be downloaded and used without charge.  Redistribution 
by any means is prohibited.  
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS 
IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 
PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR 
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  

Copyright 2002, Christopher MacDonald.