Personally I use VBR for encoding. So if it's set to 160 kbps for example (using iTunes), it may well end up being a 241 kbps as happened to me some hours ago. (or could be less than 160) Besides, digital players handle VBR much better than CBR (Constant Bit Rate) & that applies to both audio & video. Not to mention the actual encoding improvements by spending equal bit rates upon simplistic music bits compared to complex bits as happens with CBR (ie: VBR spends more bit rates upon complex audio parts than those that are more easily compressed.) I personally don't encode at below 192 unless it's a song I'm not over-enthusiastic about or "some" heavy metal or the original sound quality doesn't deserve/require high bit rates. My favourites always get 320 kbps VBR or 256 VBR.

Anything below 30 kbps is only intended for talk recordings such as perhaps comedy. I guess similar to those cheap talk cassette tapes one could buy once upon a time. Music sounded disastrous on them. But digitally, just talk is fine (I suppose.)

Oh well just my thoughts & opinion for what it's worth.

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