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WCRB-FM Off-The-Air Between Owners

WGBH is running 48 kbps for HD-1 & 2 and HD-3 is 32 kbps. WGBH HD-2 gets the same feed as WCRB's STL which is a linear 44.1 KHz. system. As of 5AM Monday, there is no compression in use at the WCRB transmitter, only modulation protection limiting. Figured we would try it this way a while and see what happens.

Rob Landry is a true gentleman and made the transition a real pleasure.
 
Don Juan said:
Scott Fybush said:
So for many stations running HD3, the allocation is now 48/48/48, or 64/32/48. It is increasingly common to see more unusual divisions of bandwidth, too - some engineers in the public radio world believe there's a "sweet spot" around 50 kbps where the current codec performs best.

Scott...is the allocation up to each station and engineer? Or is the allocation mandated by FCC code?

Also, I had heard that the HD3 stream must be in mono. Is that an FCC mandate, an iBiquity rule...or up to each station?

Correct me if I'm wrong Scott, but the only FCC mandate is that the main HD channel have equal or greater sound quality than the FM channel - which usually translates to around 64 kbps. The settings for the HD2 & 3 subchannels are up to each individual station, with some using the extended hybrid mode to add bandwith for the HD3 subchannel.
 
It's my understanding that the FCC doesn't mandate any specific split of the FM HD bandwidth, nor is there a mandate that the HD3 be in mono.
 
I think the HD3 ends up in mono because by the time they get the audio quality they want on HD1 and HD2, there isn't enough bandwidth to get stereo encoded on the bandwidth that's left for HD3
 
Freeform WBCN is in mono on ZLX -HD3. How many extra bits are there in Extended HD mode? 24 or 32kbps? Have read that the 96 kbps for HD1 and HD2 can not be shared with extended bits on HD3 for Hybrid.
Hope that GBH will use limited compression on 99.5 . Sounds good in my car.
 
I must apologize for inaccuracies in a previous posting. WGBH-HD is operating 48/48/24 mono for HD-1, 2 & 3. WGBH began operating WCRB on Tuesday at 5 AM, not Monday. Sorry for any confusion.
 
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