8 posts / 0 new
Last post
kitkat's picture
Offline
Last seen: 3 months 17 hours ago
Joined: 18/06/2007 - 09:30
Posts: 286
DAB quality

I know dab is poor quality against fm etc but can anyone explain what makes it so poor, is it just the fact that to many station fighting for space or is it low bit rates etc?

the record spot's picture
Offline
Last seen: 5 days 14 hours ago
Joined: 13/10/2007 - 14:36
Posts: 9252
Re: DAB quality

Couldn't tell you technically, perhaps Andrew or one of the other WHF folk could, but one listen to Radio Five Live at 64k then hearing the broadcast get reduced to the levels of a squawkbox garble told me that the bitrate could do with being a little higher...

ianr23gp's picture
Offline
Last seen: 8 months 1 week ago
Joined: 05/02/2008 - 11:25
Posts: 102
Re: DAB quality

Again, I'm no techie but I'd imagine there is only a fixed bandwidth that can be broadcast on. The large number of digital stations all probably have to transmit on a lower bitrate to squeeze them all in.

I'd be interested to hear if this is complete rubbish or a good guestimate...

Andrew Everard's picture
Offline
Last seen: 9 months 4 weeks ago
Joined: 30/05/2007 - 12:34
Posts: 28837
Re: DAB quality

Low bitrates, created by the need to cram as many stations as possible onto one multiplex, coupled with an inefficient coding system.

With more recent coding systems, such as the AAC-based version used in DAB+, it's possible to get much better sound quality for the same bitrate.

But of course it requires different decoding, which means new receivers...

ianr23gp's picture
Offline
Last seen: 8 months 1 week ago
Joined: 05/02/2008 - 11:25
Posts: 102
Re: DAB quality

Thanks Andrew. I've just read your other post on the 'digital Britain opportunity'.

I'm not surprised that DAB+ requires a new decoding method = new receivers.

When do you ever think a Japanese boardroom would start with the following:
"Now, let's not re-invent the wheel here. We want our customers to benefit from new technology using their existing purchases. What's a few more billion yen in lost revenue this quarter?"

Andrew Everard's picture
Offline
Last seen: 9 months 4 weeks ago
Joined: 30/05/2007 - 12:34
Posts: 28837
Re: DAB quality

Point taken, but of course we have no-one to blame but ourselves for DAB, as it was an all-European invention. The result of a protracted Eureka moment, in fact...

This also explains why the Japanese companies were relatively slow to get into DAB, why so few AV receivers have DAB tuning built-in, why the Americans didn't go for DAB and probably a whole load more things...

King Goal's picture
Offline
Last seen: 7 months 1 week ago
Joined: 25/08/2009 - 12:22
Posts: 23
Re: DAB quality

I bought a DAB radio to rid interference and was led to believe there was no interference with DAB.  Why then do I get a poor reception on some stations?  Is it due to the area you live in?

Anonymous
Anonymous's picture
Re: DAB quality

bitrates is one problem and compressed dynamic range is other. Very bad if they both used together. Some fm stations also compressing dynamic range.

Log in or register to post comments