Normalization and Equalization
Normalization is a process that increases the peak amplitude of a signal to the maximum level before clipping. All other amplitudes are then raised in their original proportions to the new peak amplitude. Equalization boosts or cuts the strength of a specified frequency or range of frequencies. The graphic equalizer found in a car stereo system is a common example of one kind of EQ device called a shelving equalizer. It divides the audible spectrum into more or less narrow bands and provides a control for boosting or weakening the strength of the frequencies within each band.
So how did all this creative activity turn out? You can hear the results for yourself; see Resources for the URL.
Bear in mind that the recording has not yet been mastered, and I still can return to my original session and make other changes. Feel free to suggest improvements, but try to be kind about my modest efforts.
Paul Davis also is responsible for creating the JACK low-latency audio server and transport control interface, so you would expect Ardour's JACK synchronization capabilities to be well evolved. I tested the Hydrogen drum machine and the Rosegarden sequencer running in JACK master and slave modes and experienced mixed levels of success. Both programs were synced to and from Ardour by way of JACK without trouble. Hydrogen got along nicely with Ardour, but I had problems recording the output of softsynths driven by Rosegarden. The Rosegarden team is aware of this issue and intends to resolve it, but you should check the Rosegarden Web site for the latest news.
At the time of these tests, Ardour's support for MTC send/receive was under heavy revision, so I was unable to complete any meaningful tests. However, MTC support is a major item on many Ardour users' wishlists, and the remaining bugs should be worked out before version 1.0 is released. Other means of synchronization may be supported in future versions of Ardour. Direct SMPTE reading, MIDI clock and SPP (song position pointer) have been suggested as likely candidates, but work on those protocols will have to wait until after the Ardour 1.0 release.
As I learn more about Ardour, there seems to be even more to learn. It's a credit to Ardour's designers that the initial interface view is clear and uncluttered, using pull-down and pop-up menus to reveal many underlying features. Also, many helpful keyboard bindings exist, but you need to run ardour -b at the command prompt in an xterm to discover them.
After gaining more confidence with Ardour's basic features, I started to explore more of its capabilities. The TM-D1000 sends MIDI messages and controller streams for most of its actions, and Ardour's controls can be bound to external MIDI control surfaces. Ctrl-middle-click on a button or fader and then activate the controller to set the binding. This feature is very cool, allowing any hardware device that sends MIDI controller streams to act as a control surface for Ardour. Incidentally, group definitions still are in effect, so you can control multiple faders in Ardour from a single external fader.
The TM-D1000 also transmits and responds to MIDI machine control (MMC) commands, a valuable feature because Ardour can control and be controlled from such a device. MMC messages include typical transport control actions such as start/stop, fast-forward and rewind. Thus, a MIDI-sensible mixer such as the TM-D1000 can function as a hardware control surface for almost all of Ardour's operations.
In an article of this length I could test only the features most relevant to my goals. I have not worked yet with Ardour's looping mechanisms, MTC still was stabilizing as I completed this article, I didn't check out the timestretch capability and so on. As I said, Ardour is a deep application, and there are many useful and interesting features not touched on in this article's use of the program.
Development activity around Ardour is intense, especially as the program closes in on its 1.0 release. Many people are interested in a viable alternative to the proprietary lock-in solutions available for other operating systems, and Ardour appears to moving along the right development path. Much work remains to be done, including improved MIDI capabilities, video track support, expanded synchronization possibilities and a GUI overhaul (GTK2 support is planned). However, Ardour currently is in a feature-freeze, with bug fixes and stability being the first order of the day before version 1.0 is released.
As might be expected in a pre-1.0 beta release of a large-scale complex project, it is not quite bug-free. Ardour's Mantis bug-tracking and feature-request system provides an excellent way to check on the status of known problems, report new ones and make suggestions for future releases.
VST plugin support currently is problematic, due mainly to continuing changes in WINE and Linux kernel development, but it is a high-priority item for the developers. Many users have expressed their willingness to switch platforms for their audio work if VST/VSTi support becomes seamless under Linux.
Similis sum folio de quo ludunt venti.
- Handling the workloads of the Future
- Readers' Choice Awards 2014
- diff -u: What's New in Kernel Development
- How Can We Get Business to Care about Freedom, Openness and Interoperability?
- Cooking with Linux - Serious Cool, Sysadmin Style!
- Synchronize Your Life with ownCloud
- Days Between Dates?
- Computing without a Computer
- Non-Linux FOSS: Don't Type All Those Words!
Editorial Advisory Panel
Thank you to our 2014 Editorial Advisors!
- Jeff Parent
- Brad Baillio
- Nick Baronian
- Steve Case
- Chadalavada Kalyana
- Caleb Cullen
- Keir Davis
- Michael Eager
- Nick Faltys
- Dennis Frey
- Philip Jacob
- Jay Kruizenga
- Steve Marquez
- Dave McAllister
- Craig Oda
- Mike Roberts
- Chris Stark
- Patrick Swartz
- David Lynch
- Alicia Gibb
- Thomas Quinlan
- Carson McDonald
- Kristen Shoemaker
- Charnell Luchich
- James Walker
- Victor Gregorio
- Hari Boukis
- Brian Conner
- David Lane