Dear Aunt TUAW,
Is there any app you know of that i could use to turn down the volume of individual/specific apps on my Mac without turning down the whole of the system.
If you've ever used it on windows seven then you'll know how useful it is.
Any apps you could recommend. i'm willing to pay (but not that much - just in case apple introduces its own solution?)
Your loving nephew,
You'll want to take a look at Audio Hijack Pro from Rogue Amoeba. With it, you can hijack each application you want to adjust and apply a filter (Auntie imagines "gain", with the gain turned down) to tweak the sound levels. You can read more about using Audio Hijack Pro for per-application volume tweaks in this write-up.
Rogue Amoeba's Paul Kafasis explains, "While Audio Hijack Pro is geared as a recording tool, we've seen lots of users taking advantage of it for audio adjustment as well. Once an app is hijacked, Audio Hijack Pro provides fantastic control over the audio output. The Mute button is handy for temporarily silencing annoying apps, and the Effects area provides all sorts of power. The Gain slider found there makes it possible to turn audio down or up. As well, plugins like Double Gain can amp things up further (helpful on laptops with weaker speakers), while the 10-band equalizer is nice to have in all sorts of apps which lack their own."
Holding your breath for a 10.8 or 10.9 feature direct from Apple? Kafasis told Auntie, "It seems rather unlikely Apple is going to add this - it's been a desire since 10.0, and has never been added."
Audio Hijack Pro offers a free trial period so you can experiment before buying.
Best of luck,