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Opus killer @128 kbps

3 years ago one of the users from my forum published the ABX log (russian) which shows that he hear difference between lossless and opus -b 128. As I understand that was opus 1.1 (October 2014)

Now I tried that sample with libopus 1.2.1 (also -b 128) and here's the result:

Spoiler (click to show/hide)

The difference is almost at hearing threshold but is perceptible and sounds like some additional high-frequency noise (Opus sounds with more sharpness than original sample).

The sample: 02_the_riddler_hide_and_seek.flac
Encoded sample: 02_the_riddler_hide_and_seek.opus

As I read in Wiki, Opus recommended bitrate for music is 96—128 kbps, but why it's restricted there to maximum of 128? Maybe it should be raised to ~160 kbps?

Re: Opus killer @128 kbps

Reply #1
Would you mind trying --bitrate 140?

(I have 2 tracks I care about which I can't really ABX at --bitrate 128 with 'reasonable effort', but I repeatedly got at 6/8. Too low a safety margin for my taste. Using --bitrate 140 I get real random ABX results.)

The wiki recommendation isn't wise in this respect to me either. We have seen in another thread that --bitrate 80 yields results which are fine usually. Even --bitrate 64 is very usable for a good quality. And if someone wants a setting which is fine also in rare situations -- bitrate 128 isn't a bad choice, but a somewhat higher bitrate maybe useful. What an exact bitrate to use depends on personal preference and personal judgement about those tracks requiring a higher bitrate (relevance and quality wise).
I'd prefer a recommendation for good quality music which reads like 64 ... 160 kbps. (OK, the wiki table is meant to provide a start-off, but I'm not sure whether everybody reads this. Even for a start-off the lowest recommended bitrate should be 80 kbps rather than 96 IMO).
lame3995o -Q1.7
opus --bitrate 140

Re: Opus killer @128 kbps

Reply #2
Although you requested 128 kbps, the download segment is actually 175 kbps, presumably trying real hard to be transparent.

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