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Tech Tips
How do I create or edit XML documents for patch names in Pro Tools 6.x under Mac OS 10.2.x?
Tip: Tired of Pro Tools 6 (and higher) automatically re-syncing sound FX folders that never change?
Why does my Pro Tools LE session clip when I open it on TDM hardware?
[26863]
How do I create or edit XML documents for patch names in Pro Tools 6.x under Mac OS 10.2.x?
Detailed information on Creating Mac OS X Patch Names & MIDI Device Definitions is available at:
http://www.digidesign.com/support/tips/xnames.html
and as an Acrobat PDF download from the bottom of that same page:
http://www.digidesign.com/support/docs/xnames.pdf
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[26622]
Tip: Tired of Pro Tools 6 (and higher) automatically re-syncing sound FX folders that never change?
Use the Mac finder to lock the folder. Pro Tools will not re-sync a folder that has been locked. This will speed up
your browser when searching through those locked folders.
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[5831]
Why does my Pro Tools LE session clip when I open it on TDM hardware?
Pro Tools LE uses the power of your CPU's processor to perform mixing and processing. A side benefit of this
technology is its ability to use 32-bit floating point math to scale the level of signals to avoid clipping (which
translates to great headroom). Signals in Pro Tools LE can indeed clip, but signal management can be easier... you
mostly have to watch output levels for mixed signal busses and bring them down so that they don't clip.
Pro Tools TDM systems use HW DSP acceleration that utilize 24-bit fixed point math. (Comparing 24-bit fixed point
and 32-bit floating point audio systems is a bit like comparing PowerPC and Intel Pentium processors... properly
implemented and designed, you can get a great result out of either one... but comparing the techniques used
directly can be difficult!) TDM systems provide 48 bits of precision at the mix bus, which allows a very large degree
of headroom as well. However, Plug-In processing in the TDM world is restricted to a 24-bit data path, so as with
most any signal processing in the audio world, some attention to level setting is necessary to avoid clipping.
For example , if you introduce a signal into a DigiRack EQ that is close to "full code" (the hottest digital level before
clipping) and you add a large boost on an EQ, you will likely clip the EQ Plug-In. Just as with any rack mounted
device, etc., you can avoid this simply by using the input attenuator control provided. The EQ Plug-In for Pro Tools
LE behaves the same way, but because all of the processing is occurring in the host computer, the levels can be
scaled for you to avoid most clipping without adjustment (other than mix outputs which require it).
Note: Some Plug-Ins use a technique called "double precision arithmetic" to provide 48 bit precision when
processing, which results in increased headroom. This is great, but keep in mind that these Plug-In do require
roughly twice as much DSP power to do their work.
Because of these differences, if you plan on exchanging sessions between Pro Tools LE and TDM systems, it can be
prudent to attenuate the input level of a Plug-In like DigiRack EQ if you have applied a large amount of boost to a
predominant frequency (like a big booming kick drum). This will avoid the possibility of clipping in the TDM version
of the Plug-In, and you'll still get to take advantage of a "24-bit clean signal" when levels are set correctly.
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USD
Why isn't Pro Tools resolving to a tape striped with LTC/VITC that I received from a European studio?