Hi, excuse my ignorance, but please help. 
I want to use drum samples from the Studio Instruments SI-Drum Kit, which are by default contained in C:\Program Files\Cakewalk\Studio Instruments\SI-Drum Kit\Kits. 
I double-click the wav files in the subfolders to listen to the samples, but what I get is just very loud unpleasant noise. 
This happens to a number of other Studio Instruments samples, such as those from SI-Strings (but not all of them generate the noise). 
Is this normal? Is it just me who experiences this? 

Thanks 

It's not just you.
I'm not entirely sure what causes it, but I believe there is something proprietary about these files.
They may be associated with an sfz or some such that is required to interpret the file.
However, if you are wanting to do what I think you are, there may be a fairly simple solution (or workaround, depending on your viewpoint).
Are you trying to use some of the SI Drum sounds along with another drum VST synth?
If so, you can insert both SI and the other VST, and use a drum map to direct specific drums to either one.
This really just a MIDI map, and the cool thing is you can send any note to any available synth.
It doesn't work with Simple Instrument Tracks. You need to insert your synths with at least one MIDI Source Track, and Synth Audio Outputs as needed.
Set the output of the MIDI source track to a New Drum Map(GM, or the SI Drum map is a good place to start).
Then open the Drum Map Manager, and select your options.
I can help walk you though it if this seems viable.
If that's not what you are after, give us a better idea of what you are wanting to do.

Hi. Thank you for confirming the noise and for replying. I’m sorry about not mentioning what I really wanted to do. Instead of what you have described, I’m wanting to load SI-Drum Kit samples into a drum sampler and create a drum kit with multiple outputs.

I have high-end drum VSTs such as the Native Instruments Drummer libraries and Steven Slate Drums 4 EX (I don't have Session Drummer because I use the Essential version of Sonar), but because they are so CPU-hungry I now prefer to use a quick and easy drum kit in a project that uses many VSTs. I could buy Easy Drummer or some other less CPU-hungry drum VST, but why not turn this nice sounding free drum VST (believe it or not I like it better than BFD Eco) into a highly usable drum library, by adding different compressors/reverbs (good ones) to its kick, snare, toms, etc.

Well, I think I'll have to give up the idea because the samples seem protected and loading six instances of SI Drums instead for my purpose is very unrealistic. Anyway, thank you for your help.

Yea, I'm thinking it might be something Cake does to prevent users from using their samples in other programs.  They want you to upgrade to their products, not use their samples w/ other company's.