I’m trying to make it sound like you are in hearing thunder while inside of a cave but I need help!
I FEEL LIKE IT IS RIGHT IN FRONT OF ME AND I’M JUST MISSING IT. 
If you want to make an effect where the pitch reduces, try Effect > Sliding Time Scale / Pitch Shift… .
If you want reverb, see Effect > Reverb… .
If you want to increase or decrease how loud certain frequencies are, use Effect > Equalization… .
Gale
Okay I’ll try it out and let you know my results.
It’s prefect thanks. I have one more question you might be able to help me out. I have and High quality recording of thunder and rain and i want it to sound like your hearing from inside of a cave. so if your in a cave and there is a thunder storm out side and you can hear the thunder from inside the cave what would be the best effects to use in your opinion?
Thanks!
This might not really help you.
Some time ago, I wrote a Nyquist code snippet to emulate an explosion in a mine.
I would probably use a long chain of echoes since the thunder bounces off all the cave’s walls.
That suggests the thunder and rain must sound as if it’s coming from a more distant and expanded space which requires a more pronounced, confined and up front stereo imaging stage within the cave to contrast against the reduced volume but more opened up sound stage of the outside thunder/rain. Tweaking Room size against Reverberance and Tone Low and Tone High settings in Audacity’s Reverb… tool might deliver these results.
Thanks. That suggests then that you may want to Edit > Duplicate the “thunder and rain” track then work on one copy as the audio inside the cave and the other copy as the audio outside the cave.
You may want to use the -…+ gain sliders on the tracks to reduce the outside audio by more than the inside audio.
Gale