Yes i understand it should be 17k by default. I had reports from a listener of
there looking like a cutoff at 15k (this was likely the source file)
Not sure why you would suggest using SBR (AAC+/HE-AAC) however. Seems like a
bunch of extra steps to achieve a similar goal as just setting the bandwidth
parameter correctly. As SBR will first encode in LC at 1/2 sample rate (thus
max frequency info will be 1/4 real samplerate, 48kHz -> 12kHz) then use SBR
bits on the decoder side to 'reconstruct' the higher frequency info, useful for
low bitrate stuff, sure... However more intensive for the decoder and as I do
choose to transmit in 320k I can afford to raise the bandwidth cutoff.
Interesting if SBR is indeed enabled by default, and would be news to me, It is
disabled in ffmpeg by default.
I do not see the point in streaming in ogg/flac, at least doubling the required
bandwidth with no apparent quality difference to fdk_aac (or any other encoder
at 320k tbh) with a correctly set bandwidth parameter...
The choice of fdkaac over vorbis (and other ogg encapsulated encodings) was due
to bugs/issues in how browsers decode chained ogg, in particular when piped
into the webaudio api (i seem to get timestamp desyncs).
The main reason for wanting to set it higher is that there is a noticeable
difference between my fdkaac streams and my equivalent ogg/vorbis streams, and
also to mirror my settings in my DASH configuration.
```
-c:a:0 libfdk_aac -cutoff 20000 -b:a:0 320k \
-c:a:1 libfdk_aac -cutoff 19000 -b:a:1 256k \
-c:a:2 libfdk_aac -cutoff 18000 -b:a:2 192k \
-c:a:3 libfdk_aac -cutoff 18000 -b:a:3 128k \
-c:a:4 libfdk_aac -cutoff 17000 -b:a:4 96k \
```
Now at low bitrate dash options there is a valid reason to use HE / SBR and I
shall look into that.
@toots thanks for making that parameter available, i will look into building
from master, however i did have issues a couple days ago due to something to do
with an incorrect return type in sedlexing_compat
I was using an opam pin, is there some other dependency i also need to pin for
this to build successfully?
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