I noticed there are associated .ho and .hdp files for each wav and ogg music loop that Magix uses (from Catooh).. what are these? They must help the program combine sounds because I have noticed when I take plain wav music pieces and try to combine them with the Magic loops or with other wav files it is much harder to get them to work together.
Thanks,
The .H0 and .HDP files are associated with audio files in MAGIX audio editing software such as Audio Cleaning Lab and Music Maker (and likely Samplitude and Sequoia). Naturally, MAGIX is not going to reveal the details of their software products, and I am no programmer. However, these two files likely record the key, BPM, and other editing information of audio files used in these programs.
So, as you've noticed there are .H0 and .HDP files associated with the media files from CATOOH. This is likely because some of this content is created sold by third parties and not MAGIX. Whereas, the soundpool files from MAGIX do not have these files until they are inserted into an arrangement. However, the soundpools and the files from CATOOH are tagged with information, such as the BPM. Many of the soundpools actually list the BPM of their audio files in the program.
This information is important for the reason you site. If you have the program set to do so (which is the default), any of these audio files inserted into an arrangement will automatically be adjusted to the arrangement tempo. As you noted, this makes working with these files MUCH easier. This feature can be turned off in the Program Settings if desired.
In MMM, you can use the Beat Finder to assign the BPM to other audio files so that they too will automatically conform to the arrangement tempo. However, this feature works best on audio files that have a clear, steady and distinct beat. If the file does not have these things, the Beat Finder tends to "lose the beat". I haven't tried using it on audio files that lack a beat because it would obviously be an act of futility.
Thanks for your very clear and informative answer, Procyon. I was thinking they might also be a record of changes to the ogg/wav file when used in a altered state as part of a new composition. I've noticed that Sony Acid, the Cakewalk Music Creator, Acoustica Mixcraft and other music programs all seem to also use some sort of proprietary file that is linked to the main sound file. Some of these programs state clearly that the original sound file is not altered though.. I could find nothing about this in the MM MX18 pdf manual or on line, but I may have missed it.
I haven't bought any yet from Catooh, (waiting for MX18 to arrive next week), but I wonder if their "sound packs" and "instrument packs" also contain these ho and hdp files? Has any one used them?