What equipment / software do you [teh devs] use for recording sounds, music tracks, voice, and everything audio related? I’m interested and have a friend in the biz who is impressed with your work… I didn’t tell him where the music came from 
Imma get him some audio stuff for his birthday.
Thankya
You could have used the Ask the Devs thread to ask your question, no actual need to make a new thread.
Founded in 2004, Leakfree.org became one of the first online communities dedicated to Valve’s Source engine development. It is more famously known for the formation of Black Mesa: Source under the 'Leakfree Modification Team' handle in September 2004.