Old 27th July 2013, 14:18   #1
centerm
Junior Member
 
Join Date: Jul 2013
Posts: 7
Quality loss when broadcasting live through sc_trans2

I'm using Shoutcast and sctrans to transmit into aacPlus, in case 32kbps. The audio sctrans is perfect, but when I connect (using the alternate port, not to stop the sctrans) audio broadcast live has a major loss of quality.
Is there any procedure that can be done to minimize this loss?
centerm is offline   Reply With Quote
Old 27th July 2013, 14:58   #2
DrO
 
Join Date: Sep 2003
Posts: 27,873
there is going to be audio loss as you're likely transcoding something which has already been transcoded from the DJ source being used and transcoding something which is already transcoded will do that.

other than ensuring the DJ source is connected at as high a bitrate as needed for the stream(s) coming out of sc_trans to try to lessen the impact of throwing more audio data away, there's not too much you can do about it.
DrO is offline   Reply With Quote
Old 27th July 2013, 16:01   #3
centerm
Junior Member
 
Join Date: Jul 2013
Posts: 7
Sorry for my English (translator - I'm brazilian)
What I realize is that there is no loss in audio quality in itself, but a part of the audio. Whenever I start to hear an audio aac, it starts to sound like it's mono sound, one second and then goes the rest of the audio (which gives the highest quality audio). It is this last part of the audio that seems to get lost when transmitting live using sctrans.
I could not quite understand what u mean by increasing the quality, as already tested in various qualities and always the sound loses this part "stereo"
centerm is offline   Reply With Quote
Old 27th July 2013, 17:16   #4
DrO
 
Join Date: Sep 2003
Posts: 27,873
what I mean is the DJ source needs to be providing a higher bitrate than what you provide to the listeners e.g. 320kbps even if the output is going to be 32kbps.
DrO is offline   Reply With Quote
Old 27th July 2013, 17:42   #5
centerm
Junior Member
 
Join Date: Jul 2013
Posts: 7
320kbps is high for Brazilian connections, but I'll try to test here.
centerm is offline   Reply With Quote
Old 27th July 2013, 18:50   #6
DrO
 
Join Date: Sep 2003
Posts: 27,873
that was just an example. you'll probably need to try different inputs to see what works. also make sure you haven't changed any of the aac encoder settings in the sc_trans concig file ie you just left it use the built in defaults.
DrO is offline   Reply With Quote
Old 27th July 2013, 19:02   #7
centerm
Junior Member
 
Join Date: Jul 2013
Posts: 7
Actually use the panel CentovaCast 3, have released a 500kbps limit for this test account and tried to connect with 320, but the server stop. I will compare the configuration file to see what might be happening. Thanks for the help.

Tested at 128 and 160kbps and the loss of quality is now almost imperceptible.
Thank you again.
centerm is offline   Reply With Quote
Reply
Go Back   Winamp & Shoutcast Forums > Shoutcast > Shoutcast Technical Support

Tags
live, sctrans

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump