Sound Empire Caster AAC streaming

[greekradio]

Hi all,

I'm using Sound Empire Caster 1.2.7 to send a live feed from my home studio to a community FM radio station. It works well.

In the past I was streaming to the station's master control studio (via Icecast server) in mp3 at 320 kbps, and a month ago I switched to AAC at 320 kbps.

However, in AAC mode, I noticed that the server (and all players) detect the stream as AACplus (Content Type: audio/aacp) instead of AAC-LC (Content Type: audio/aac)

In BUTT (another encoder) it automatically selects the best AAC profile for the chosen bitrate. In bitrates below 48 kbps BUTT defaults to AAC+v2, between 48kbps and 96 kbps BUTT defaults to AAC+v1 and above 96kbps BUTT defaults to AAC-LC.

With SECaster it doesn't appear to be the case.  Above 96 kbps, there's no need for Spectral Replication (synthesized high frequencies) used by AAC+.  AAC-LC is best for high bitrates.

So my question is:  is there a way to have SECaster stream in AAC (AAC-LC) at high bitrates (ie 320 kbps)? Selecting AAC in SECaster, streams in AACplus. Is this a bug?

Thank you.

[DJ Garybaldy]

AFAIK AAC only goes up 128kbps

[greekradio]

AAC (AAC-LC) can go up to 320 kbps, and at that bitrate it achieves "transparency".

AAC+ (HE-AAC v1) is typically used at mid-to-low bitrates, typically 48 to 128 kbps.
AAC+ (HE-AAC v2) is typically used at very low bitrates, below 48 kbps.

It appears that the "AAC profile" in SECaster is in fact an AAC+ codec.

The implementation of AAC in SECaster seems incorrect.

[DJ Garybaldy]

Unless you speak Russian there isn't a fat lot you can do about it. Its developed by a developer from Ukraine.

There are other encoders you could use.

[greekradio]

I'll stick to SE Caster, I really like the interface. But I'll revert to MP3 320 kbps to link my home studio to the FM Radio Station.

Surprisingly, NAUTEL, a respected high-power commercial AM/FM Broadcast Transmitter manufacturer highly recommends Sound Empire Caster for Studio-to-Transmitter VoIP link in their documentation.
http://support.nautel.com/content/user_files/sites/2/2019/06/Streaming-Configuration-Josh-Bohn-NUG2019.pdf

I'll try to get in touch with the developer of SECaster if he can fix the AAC implementation.

In the mean time, broadcasters should avoid using AAC mode in SECaster.

[DJ Garybaldy]

The sound Empire Caster forums are here if its any use http://se2.com.ua/phpBB/viewforum.php?f=13

[greekradio]

Thanks.

I think I'll give BUTT a try. It appears it's more consistent with updates and serious about codec implementation.