At the Sounding Edge: Introducing seq24
The Performance editor (Figure 4) also is easy to use. Right-click and hold to bring up the pencil edit cursor, and left-click while holding to enter or delete a pattern. Concurrent patterns are allowed, and patterns can be added or removed in real time. Playback is either normal or defined by the loop points. The loop points are moved by selecting one of the L/R markers with the appropriate mouse button—left for L, right for R—and then clicking with the same button at the new location. The loop points also can be edited in real time.
The three buttons in the top-right corner of the editor expand, collapse or expand and copy the material between the L/R markers. They are simple but useful tools for working with larger formal designs and elements of a composition.
Saving your work in seq24 is as uncomplicated as the rest of the program. Select File/Save As, give your work any name you like, with or without any extension (MID is best), click OK and that's it. From that point on, you simply can use File/Save. Reloading your work is equally simple.
seq24's native file format is the Format 1 standard MIDI file format. seq24 also can load a MIDI file and break its individual tracks into sequence containers. This feature is another neat musical extension to seq24's utility, offering new possibilities for material from other sequencing environments.
Despite its evident simplicity, there is more to see in seq24, but the program is easy to learn. Complete documentation is found in a brief text file named SEQ24. Also, starting the program with the --help long help option lists the available command-line options. The tooltips help is well-written and should clarify the interface even for complete beginners.
As a final tease, I leave you with the screenshot in Figure 5 to illustrate seq24 accompanied by some friends and helpers. seq24 manages its MIDI I/O internally (see above), and the synths it drives in the screenshot are all JACK clients. I use QJackCtl's audio connections panel to route the audio data to and from my selected synths and effects processors. In Figure 5, the output ports for QSynth and amSynth are connected to the JACK Rack running a single LADSPA plate reverb plugin. The processed output from the JACK Rack is connected to the ALSA PCM audio output ports. ZAddSubFX has its own effects, so its output is connected directly to the PCM ports.
Thus, I have seq24 driving QSynth, amSynth, ZynAddSubFX and my SBLive's EMU10k1 synth (internal connection), with two of these devices routed through a software reverb unit. If you'd like to hear what this system sounds like you can visit this page for some brief examples in the OGG audio format. They're not complete pieces, but they should give you an idea of what can be done with some of the modern Linux audio and MIDI software now available.
seq24 can be invoked as a JACK transport client, giving it synchronization capability as either a JACK master or slave. Alas, my tests failed, which may be due to my JACK version. JACK sync is a cool feature, so I'll keep checking in on this one. Judging from the tarball's TODO file, other likely additions might include a few more edit functions and some randomization routines.
seq24 is not a complicated program. It has been designed for speed, stability and efficiency. Admittedly, it is short on editing functions and long on usability, but its features are well chosen and musically useful. It's also incredibly addictive fun, as befits any serious musical instrument.
Dave Phillips is a musician, teacher and writer living in Findlay, Ohio. He has been an active member of the Linux Audio community since his first contact with Linux in 1995. He is the author of The Book of Linux Music & Sound, as well as numerous articles in Linux Journal.
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.
Free to Linux Journal readers.Register Now!
- SourceClear Open
- SUSE LLC's SUSE Manager
- My +1 Sword of Productivity
- Tech Tip: Really Simple HTTP Server with Python
- Doing for User Space What We Did for Kernel Space
- Parsing an RSS News Feed with a Bash Script
- Managing Linux Using Puppet
- Returning Values from Bash Functions
- SuperTuxKart 0.9.2 Released
- Google's SwiftShader Released
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