quadsearcher
1K Club - QQ Shooting Star
- Joined
- Nov 8, 2010
- Messages
- 1,197
What you write above is true, but not the whole story.
For lossy codecs AC3 and DTS, which use psychoacoustic models, there is no simple relation between bitrate and audible quality. They also don't 'use' bits the same way. In fact they are hard to compare fairly. And in the few actual controlled listening tests, there's no clear winner, despite all the audiophile mythology about 'Dullby'.
As for MLP (lossless) vs lossy, there's also a knee jerk contention that lossy will sound worse. That too is highly dependent on conditions. Regarding lossy multichannel, note a general rule as per Dr. Toole that as you add channels from mono to stereo to multi, reliable discrimination of audio quality decreases. (It's why Toole/Olive's famous speaker preference studies used *single* loudspeakers.
OK. That fits with some information I've skimmed, and subjectively, I wouldn't disagree. There was some Fleetwood Mac MC disc that was only released as a lossy codec but it sounded just fine. Nothing to compare it to, but sounded fine.
For me, the interest I have in wanting to pin down a relationship between audible quality and codec , which I understand is generally not possible between lossy codecs and may be difficult or not practical to perceive between lossless and lossy, is that before my discs rot, tapes get sticky, or decent cartridges are unavailable, I want to back everything (RAID etc.) up as others have. I would lose what's left of my mind to attempt to decide which codec on each disc is most worthy of converting to FLAC for archiving, so it seems to me that of the three streams of a DVDA, MLP is digitally closest to original (WAV) so I should pick that one.
Now knowing that DTS and AC3 are not necessarily hierarchical, if MLP is not available on a given disc, I probably would use a flawed A/B comparison briefly and not think too much about it, I'd convert/archive one of them. Flip a coin or something.
Dr. Toole? Olive? Piques my interest.