At the Sounding Edge: FreeWheeling
Basic operation of FreeWheeling is easy. Audio input can come from a record-enabled mixer channel, an OGG-encoded soundfile or the internal synthesizer. The main display shows the input sound as it passes through FreeWheeling (Figure 2). By default, four input channels are defined with separate volume control by pressing the up or down arrow key and the input channel number (1,2,3,4). Press a QWERTY key to record a segment and then press it again to play the recording as a loop. Repeat this basic procedure with other keys, using any previous loop as real-time accompaniment. The u key deletes the last recorded loop, Space+[key] deletes the loop at [key] and Alt-Space deletes all current loops. F8 saves the last recorded loop as an OGG file, while F7 saves an entire collection of loops as a scene. Synth patches, audio loops and scenes all are selectable from FreeWheeling's browser. The b key rotates the browser through its loadable types, the keypad + and - keys scroll the available items for each type and the Enter key selects and loads an item.
Recording may be freestyle, timed to a prerecorded loop or coordinated with FreeWheeling's metronome. A tap tempo feature provides a neat way to set the metronome. During playback, loops can be toggled on and off by pressing the associated key. Loops can be muted and unmuted with the keypad - and + keys, plus the loop key. Volume control is available per I/O channel and per loop, giving the performer finer control over the overall balance.
I've recorded some simple examples demonstrating these features and placed them on-line here. They're not especially musically valuable, but they should give you an idea of what can be done at even FreeWheeling's most basic levels.
Now we go a few steps further in our explorations and look into the .fweelin.rc file. This file is an XML-based configuration file through which FreeWheeling's features can be customized extensively, including its interface layout, keyboard bindings, MIDI control assignments and more. You'll need to spend a little time to learn the configuration syntax, but the file, which is also FreeWheeling's primary documentation, is written clearly and is definitely worth the effort.
The easiest way to use .fweelin.rc is to change some of the default values, restart the program and check out what changes were made. For example, I changed this setting :
<!-- Soundfonts to load. Soundfonts without a path load from /usr/local/share/fweelin/. --> <fluidsynth soundfont="basic.sf2"/>
with this line:
to load my preferred soundfont for FreeWheeling's internal FluidSynth.
This simple example sets FreeWheeling's display size more to my liking:
The next example presents a more interesting use of .fweelin.rc, binding MIDI key numbers to toggle loop recording and playback. First we go to the Variables section and set the noterange variable to the desired range of MIDI note numbers, in this instance, the lowest octave of my CZ101 MIDI keyboard:
<declare var="VAR_noterange" type="range" init="36>47"/>
In the video section, we find this layout design:
<layout id="1" name="MIDI Keyboard" scale="0.35,0.55" pos="0.00,0.00" label="0" elabel="0" namepos="0.02,0.02" show="0">
The Tab key toggles between the PC keyboard, layout id 0 and the MIDI keyboard displays. By default, FreeWheeling opens with the PC keyboard layout, but that also can be redefined.
The startup section of .fweelin.rc defines the map between my CZ101 keyboard and FreeWheeling's MIDI layout:
<!-- Sub 0: Startup - do startup stuff --> <binding input="go-sub" conditions="sub=0" ... output2="video-show-loop" parameters2="layoutid=1 and loopid=VAR_noterange+VAR_loopid_pianostart" ... />
The video-show-loop event defines the range of loops displayed. Each recorded loop is assigned a unique ID number, loopid, created by summing the value of the received MIDI note number and the value of the loopid_pianostart variable. The pianostart variable also is defined in the Variables section:
<declare var="VAR_loopid_pianostart" type="int" init="350"/>
Figure 3 shows off FreeWheeling recording an audio input while playing back loops assigned to the MIDI keyboard layout. When I press the lowest key on my CZ101, a loop is recorded and assigned to the corresponding key in FreeWheeling's MIDI layout. Pressing the key again plays the assigned loop, as seen in Figure 3.
The MIDI key binding is defined in the Trigger Loops section:
<binding input="midikey" conditions="notenum=VAR_noterange and keydown=1" output="trigger-loop" parameters="loopid=notenum+VAR_loopid_pianostart and vol=velocity/127"/>
If a MIDI key press occurs that equals a note number defined within VAR_noterange, then the conditions are met and a trigger-loop event takes place, either recording or playing a loop on the MIDI key layout.
As I said, it takes some effort to get your mind around FreeWheeling's customization options and syntax, but it does start to make sense and it does result in a highly personalized instrument.
Similis sum folio de quo ludunt venti.
Practical Task Scheduling Deployment
July 20, 2016 12:00 pm CDT
One of the best things about the UNIX environment (aside from being stable and efficient) is the vast array of software tools available to help you do your job. Traditionally, a UNIX tool does only one thing, but does that one thing very well. For example, grep is very easy to use and can search vast amounts of data quickly. The find tool can find a particular file or files based on all kinds of criteria. It's pretty easy to string these tools together to build even more powerful tools, such as a tool that finds all of the .log files in the /home directory and searches each one for a particular entry. This erector-set mentality allows UNIX system administrators to seem to always have the right tool for the job.
Cron traditionally has been considered another such a tool for job scheduling, but is it enough? This webinar considers that very question. The first part builds on a previous Geek Guide, Beyond Cron, and briefly describes how to know when it might be time to consider upgrading your job scheduling infrastructure. The second part presents an actual planning and implementation framework.
Join Linux Journal's Mike Diehl and Pat Cameron of Help Systems.
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With all the industry talk about the benefits of Linux on Power and all the performance advantages offered by its open architecture, you may be considering a move in that direction. If you are thinking about analytics, big data and cloud computing, you would be right to evaluate Power. The idea of using commodity x86 hardware and replacing it every three years is an outdated cost model. It doesn’t consider the total cost of ownership, and it doesn’t consider the advantage of real processing power, high-availability and multithreading like a demon.
This ebook takes a look at some of the practical applications of the Linux on Power platform and ways you might bring all the performance power of this open architecture to bear for your organization. There are no smoke and mirrors here—just hard, cold, empirical evidence provided by independent sources. I also consider some innovative ways Linux on Power will be used in the future.Get the Guide