Podcast sample rate

RS richard22j at zoho.com
Wed Jul 19 06:13:01 PDT 2017

>From: Vangelis forthnet Sent: Monday, July 17, 2017 21:24

>... If you are referring to the original *low radiomodes as fetched by GiP, 
>then, and someone correct me, please, if I'm wrong, I believe 48.0kHz SR 
>applies to hardware/software media players which are capable of reproducing 
>the SBR portion of the HE-AACv1 encode; for SBR incompatible players, only 
>the LC portion is played back at half the SR, i.e. 24.0kHz (resulting in 
>most higher frequencies of the spectum being muted...).

Further to my previous reply, I have been wondering whether the same problem 
occurs with television sound.  HLShd delivers 96kbit/s audio, so I wondered 
if it had a SBR (Spectral band replication) component which would result in 
the sampling rate being reduced to 24khz for players which did not support 

The answer seems to be that some programmes do use SBR and some don't. 
Recent studio and outside broadcast programmes seem to use AAC-LC so there 
is no SBR and the 48kHz sampling rate is preserved, although at least some 
of the Wimbledon coverage had SBR.  A few weeks ago there was a repeat of a 
Talking Pictures programme on Lord Olivier and that had SBR.  When older 
films are made available on the iPlayer some use AAC-LC and some have SBR.

Of course if you want the 256kbit/s AC3 stream you won't get that on the 
iPlayer.  You'll have to record the satellite broadcast.

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