This is definitely better than some of the others out there. I threw together some comparisons here at 7kb/s for mp3/opus/aac: https://non.io/TSAC-Comparisons
Happy to add other comparisons if others want any.
Overall, it's FAR better at these lower bit rates, but that doesn't mean it's necessarily good. One issue I see off the bat is that volume is fairly inconsistent in the output for TSAC, which makes stereo in particular quite hard to listen to with the volume "flickering" in each channel independently.
Also I don't seem to be able to access your page, so there might be error.
Finally, when doing opus comparison it's good now to denote if it is using Lace or NoLace decoder post processing filters that became available in opus 1.5 (note, this feature need to be enabled at compile time, and defying decode a new API call needs to be made to force higher complexity decoder) . See https://opus-codec.org/demo/opus-1.5/
I've encoded xHE-AAC at 6 kbit/s mono, which is the closest match I could get. It performs much better and is widely supported (Android 9/iOS 13/macOS 10.15/Windows 11), although there are no free low bitrate encoders available yet. I used the Fraunhofer IIS Pro with EZ CD Audio Converter. It would be great if you could add it: https://filebin.net/x46m1x7n6d2t7e6b
This is the codec that TSAC extended, so it could be a nice comparison to see. I'd also echo Vocos (from sibling comment), it operates on the same Encodec tokens but generally has better reconstruction quality.
This is definitely better than some of the others out there. I threw together some comparisons here at 7kb/s for mp3/opus/aac: https://non.io/TSAC-Comparisons
Happy to add other comparisons if others want any.
Overall, it's FAR better at these lower bit rates, but that doesn't mean it's necessarily good. One issue I see off the bat is that volume is fairly inconsistent in the output for TSAC, which makes stereo in particular quite hard to listen to with the volume "flickering" in each channel independently.