After posting about loops usage in UT's, solidrock responded with good information.

Also Jim has been giving me a bit of guidance and testing for some
of my UT's.

He sent me this nice writeup on Loops.
For me, it was very informative.
With his permission did this posting.

Quote:
by Jim Fogle.

Loops can either be audio or midi based. Most people think loops are just half, measure, one measure, two or four measures in length. In fact, loops can be any length; all it has to include is a pattern that will be repeated more then once.

For the most part when people speak of loops they are thinking about audio loops so that's what I'll concentrate on so when I say loops from now on, I'm talking about audio loops.

Generally loops are half, one or two measures in length. They can be 16 or 24 bit wave (Windows), AIFF (iOS) or REX (Reason). Wave files are additionally available as general audio or Acidized wave files. Some people convert loops to MP3 or WMA file format but that is normally not a good idea. We'll concentrate on wave and REX files since those are the most popular.

You can use any audio editor (such as Audacity) to divide an audio file into segments. If a segment contains a complete rhythmic pattern, it's a loop. It requires very precise editing to make sure there are no extra samples before the start or end of the pattern. If you're even one sample off, the error will be compounded each time the loop repeats. That's the most common error people makes when they first start making loops.

One problem using loops is, dependent on the composition of the audio contained in the loop, the loop has limited time or pitch shifting capability until artifacts degrade the audio output.

Acid, an audio editing software package by Sony, embeds pitch and tempo information in the loop header to help minimize artifacts. It's not perfect but when other software packages are able to read an "acidized" loop the loop's time and pitch shifting capability can increase about 300% as compared to the same loop before it has been acidized! Even if a software package can not read the acid embedded information, it still can use the loop as an audio loop or audio file.

Reason uses a different approach. The software scans the audio file, identifies all the waveform peaks, then divides the audio file into many peak-to-peak slices. Each slice can be play, pitch or time shifted. The slices can also be moved around within the audio file into a new order. This is how the stutter effect is created. Few software packages can import, read or use REX files. Sonar is one of the few that can.

FrankB

Down The Street vs2015 12-03-2014
Win7, AMD QuadA8-5500,16GB,2TeraHD, Komplete 10
PG Ultra Plus 2016,Alesis 12USB, Sonar Platinum