The sound of thunder is one of the most relaxing and sublime sounds in nature and capturing it's uniqueness is one of the things we do here. But simply recording thunder claps is just the beginning of the process. Here are a few examples of a single thunderclap's digital transformation into a virtually real thunderclap.
Here is a the sample we begin with. A simple mono recording of thunder:
Here is the same recording with a little stereo rumbling added:
The same recording with audio depth to enhance its 'spatial' quality. In this particular case this is done by adding the same sound byte slightly offset and panning in the mirror opposite of the original clip at a lower volume. The idea behind this is to simulate the separation of our left and right hearing:
And finally enhancing the finishing rumble:
When it finally does gets mixed into a dreamscape it might go through more digital manipulation (i.e. noise and distortion cancelation, rate adjustment and such) But why all this work for a single thunderclap? Simply because those nature sound machines never did it for me. I could always pick up on the looping involved and soon their effectiveness would wear off... not to mention the lack of quality in the recordings. I think the sound of thunder is more relaxing, and therefore sleep inducing, if you can really picture yourself in the intended environment.