User Guide

MY COMPACT DISC RECORDER USES A FILE TYPE WITH AN RBK EXTENSION. WHAT IS
AN RBK FILE AND CAN I OPEN IT WITH SOUND FORGE XP?
RBK files are raw PCM sound data files. These files are used by some compact
disc recorders to store Red Book audio onto a compact disc. RBK files are data-
only and contain no other information. They are stored as 16-bit, stereo data
with a sample rate of 44,100 Hz.There are a number of things that make them
different than a normal 16-bit raw file:
• The channels are stored in reverse order
• The data is stored in Big Endian format (Motorola)
• The data length of the file has to be a multiple of 2,352 bytes (1 CD sector).
The size of a CD sector is calculated as follows:
1 second of 44.1k, 16 bit, stereo audio = 176,400 bytes
CD audio has 75 sectors of data for each 1 second of audio
Sector size = 176,400/75 = 2,352 bytes
To open an existing RBK file, use the Raw File type in Sound Forge XP’s Open
dialog (File menu) and select the RBK preset. Remember that you will have to
swap the channels if you want to maintain the correct left/right channel
settings.
EFFECTS
WHY DO SOME EFFECTS TAKE SO LONG TO PROCESS?
Some processing functions used by Sound Forge XP are very math intensive.
Examples include EQ and the reverb effect.This means that millions of integer
and floating-point arithmetic operations must be performed for each second
of sampled data. Even with a powerful, co-processing machine, high
resolution sound editing can tax a system resources.
Of course, running effects on stereo, 44,100 Hz, hour-long files will slow any
system. If you are going to be deleting or inserting space into these huge files,
it is more effective to break the files into smaller ones and then mix the
smaller files together once you are done processing them.This can be especially
necessary when you insert or delete from the beginning of a large file, since
Sound Forge XP must shift the entire file over during processing.
APPENDIX B
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