traKmeter

Screen shot of traKmeter

About

Loudness meter for correctly setting up tracking and mixing levels.

Digital recordings

The digital revolution brought a lot of advantages to the field of audio processing such as higher fidelity, less noise and non-degrading copies. Unfortunately, however, digital audio also introduced some problems of its own.

Whereas the analog domain is relatively inert against very high levels (overdriving some analog equipment actually sounds pretty good), the digital domain punishes even small transgressions into forbidden territory with harsh clipping.

Gain staging

Professional analog audio equipment is designed to be run at a nominal level of +4 dBu (1.23 VRMS) and leaves a headroom for peaks of about 20 dB. This in turn is consistent with the maximum crest factor of analog audio signals.

Let’s transfer this to the digital domain. As the maximum crest factor of analog audio signals amounts to 20 dB, the headroom can be adjusted accordingly by setting average input and output levels to -20 dB FS RMS.

Another recommendation is that peak levels should not exceed -9 dB FS (see EBU R68-2000) during tracking. This will leave enough space for inter-sample peaks, audio peaks that lie in between two successive samples and may lead to unpredictable clipping during digital-to-analog conversion.

Why traKmeter?

Most digital audio equipment sadly only has peak meters. This is readily understandable as you want to avoid digital clippings by all means. However, the lack of average meters makes correct gain staging almost impossible.

For gain staging, you need average meters or – even better – a combination of peak and average meters. And this is were traKmeter comes in.

traKmeter has an average level meter that is centered around -20 dB FS RMS and a peak level meter that is aligned to -9 dB FS. It supports stereo and 8-channel audio signals, has two scales, two ballistics modes and is very easy to use. Additionally, all meters have been thoroughly validated.

Details

Platform:
GNU/Linux
Windows XP (and above)
Language:
C++
Type:
LV2 plug-in
VST plug-in (v2.4)
standalone executable

As traKmeter was coded using cross-platform code, it should be easy to compile a version for Mac OS X. I just don’t have a Mac…

In case you want to help, please see the manual for ways to contact me. You’ll need sufficient experience in coding, compiling and debugging, though, so no beginners please!

Releases

The current version is 1.05.0 (built on 2013-05-30). Source code can be downloaded from GitHub. For information on changes and new features, please see the release notes.

GNU/Linux

32 bit version:
LV2 plug-in
VST plug-in
Standalone
64 bit version:
LV2 plug-in
VST plug-in
Standalone

Windows

32 bit version (recommended):
VST plug-in
Standalone
64 bit version (experimental):
VST plug-in
Standalone

Bug reports

Please report bugs using the traKmeter bug tracker. You may also use the bug tracker to place your wishes or ideas.

Donations

traKmeter is free software, and I’m not going to ask for money. Period.

In case you still want to show your gratitude, simply donate to a cause of your choice and tell me about it. Thanks!

License

This is free software and licensed under the GNU General Public License version 3 (GPLv3).

Please note, however, that the ASIO and VST SDKs are not free. I have used them because they are de facto standards that make life easier for musicians and engineers who just want to make some great sounding albums. Their licenses also do not interfere with creating free software.

But if you are a free software advocate, you might not want to use the VST plug-in. The pre-built GNU/Linux stand-alone and LV2 plug-ins really are free software in the sense of the Free Software Foundation. And you may build a Windows stand-alone that does not make use of the ASIO SDK. Hmmm, being a free software advocate, you probably haven’t heard of Windows, so forget about the last sentence… :)

Software
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