Well, if we stick with finance-related translations, 信用 would make more sense as (financial) credit, though I'm not sure whether I could argue any substantial difference between madness and mania. 狂騒 is the term used in Japanese to describe the Roaring Twenties, which does relate to rampant market speculation and ultimately the 1929 stock market crash, but I'm not finding any direct usage link here. It would have more to do with speculative frenzies and a stock market mania than a mental breakdown of an individual after losing all their wealth, though. 狂騒 isn't a medical term.
Most likely, you didn't see my original mention of it because it was an edit; I thought I made the edit pretty soon after the original comment and that it was plausible you loaded the page and wrote up your response after I made the edit, but I guess not.
As for onomatopoeia, this resource might help?
You can type in transliterations directly or copy in plaintext, and it offers various translations/explanations to go with it. Though as a side note, faithless's text is written with all hiragana replaced with katakana to indicate her rough voice, and this can confuse machine translation very easily. She does have a lot of onomatopoeia, but I expect you'll also get garbled nonsense even outside of that.
Most likely, you didn't see my original mention of it because it was an edit; I thought I made the edit pretty soon after the original comment and that it was plausible you loaded the page and wrote up your response after I made the edit, but I guess not.
As for onomatopoeia, this resource might help?
You must be registered to see the links
You can type in transliterations directly or copy in plaintext, and it offers various translations/explanations to go with it. Though as a side note, faithless's text is written with all hiragana replaced with katakana to indicate her rough voice, and this can confuse machine translation very easily. She does have a lot of onomatopoeia, but I expect you'll also get garbled nonsense even outside of that.