Sound Quality Vs. Measurements

[dvv]

That's funny...

I watch BBC 1 and BBC Entertainment at home, as well as CNN amd Bloomberg, plus the inescapable Sky, and I find BBC has the best sound overall and in general. Clean and clear like a whistle, with good dynamics.

CNN is also good, but somehow it's a little too dynamically flat for its own good. Bloomberg is below par, altthough still acceptable.

Sky is surprisingly good, I suspect in part because they also show Fox Crime and Fox Life, plus they own one of local national TV stations, so I suspect they saw reason in investing into quality gear and training local staff.

[Mark.Clappers]

It depends on what DVB standard you receive.

For "normal" DVB-T it's MPEG2 for HD DVB-T usually MPEG4.

But the bitrates used vary wildly (and so does the quality). A 64QAM 8K CR2/3 GI1/4 DVB-T multiplex is ~ 31Mbit /sec (from the top of my head) usually containing up to 5 TV channels.

DVB-C usually does a little better with regard to bandwith (modulations used are usually QAM64,128 & 256 depending on the S/N ratio of the cable network).

[Mark.Clappers]

I was wrong, the effective bit rate of a DVB-T multplex 64QAM 8K CR2/3 GI1/4 is ~20Mbit /sec. This would yield ~3.5Mbit /sec if 5 TV stations are in the same multiplex. Not a big surprise the quality isn't always top notch..

http://www.dvb.org/technology/fact_sheets/index.xml

[Pano]

Originally Posted by john dozier

I wish I had worked for the BBC, those folks know how to do it right. Even their streaming audio is excellent and IMHO the best in the world. Regards

Yes, very good stuff. But other national broadcasters do a great job. Having spent a bit of time at la Maison de la Radio (Radio France) in Paris and many years listening to the FM feeds, I can say they do a very good job. To my ear, as good or better than the Beeb.

Radio Netherlands also do great work.

[Pano]

Originally Posted by dvv

Frankly, I don't know. Put it this way - while a normal 16-bit Red Book file takes up say 33 MB or so, in WMA format this will shrink to about 5 MB, a compression ratio of say 6.5-7.2:1, or so.

Thanks for the reply. That's probably a 192 kbs setting. As you say, should sound mostly OK, but not as good as lossless. I doubt I could tell the difference in most cars, I know for sure not in mine!

[dvv]

@Pano

As I said, the greatest problem as is are the high range speakers, which are greatly subdued to my mind. I need a +8 dB treble lift to get them into what I hear as a normally balanced top to bottom range. Having experienced similar feelings elsewhere, and knowing that once you change the factory installed speakers for something half decent, +8 dB would cause screaming and demand I lower this to +2 dB worst case.

At least, that's what happened with the old car.

On the plus side, new speakers also afforded me a lot more general clarity and coherence, not like at home, but rather good for a car. Certainly good enough to satisfy my car listening requirements. And trust me, I really don't demand a lot from a car audio system, just decent is good enough.

[nigel pearson]

Originally Posted by Pano

Yes, very good stuff. But other national broadcasters do a great job. Having spent a bit of time at la Maison de la Radio (Radio France) in Paris and many years listening to the FM feeds, I can say they do a very good job. To my ear, as good or better than the Beeb.

Radio Netherlands also do great work.

Driving around Europe especially Germany is excellent . The bosses RDS Sony was excellent . I listened all night driving from the Austrian boarder to North Germany . The RDS seamless . If we loose FM we loose that which for most is the best hi fi they ever had . That Sony and Quad 63 's would interest me . I bet it would be stunning .


My little Sony portable ( $60 ) is almost as good as my old Quad FM3 . Certainly better than all digital alternatives . The now defunct TV 10 bit Nicam was sometimes the best . I put that down to balance on a particular night ( eg R3 and BBC TV simultaneous transmission ) . I think I could detect that the FM ( 13 bit ) had more detail when almost equal . Apparently the BBC did transmit some 13 bit . 10 bit was chosen because it is more durable ( Wales , multipath ) . A test transmission to Brighton gave no picture yet excellent sound in 10 bit as the first public demonstration ( 10 miles outside of TV range ) . I would guess 2 uV signal . This is from memory , someone from the BBC might know more accurate information . If only we could have the 13 bit's to listen to in digital . My FM3 I am sure is not the reason why it sounds good . It must be adding 1% distrotion and plenty of hiss ? I was looking at 10 bit encoding . Whilst not perfect it might be interesting .

[nigel pearson]

Just lifted this from a discussion about Chaos Theroy .

Chaos was observed by a number of experimenters before it was recognized; e.g., in 1927 by van der Pol[52] and in 1958 by R.L. Ives.[53][54] However, as a graduate student in Chihiro Hayashi's laboratory at Kyoto University, Yoshisuke Ueda was experimenting with analog computers and noticed, on Nov. 27, 1961, what he called "randomly transitional phenomena". Yet his advisor did not agree with his conclusions at the time, and did not allow him to report his findings until 1970.[55][56]

Op amps were intended to be this . I wonder if polynomials explain all ? The starting point is always the difficulty . Chaos is not random .

[dvv]

Is anyone alive here, or am I expecting messages from zombies? :-))))))))))

[benb]

I think some are entertaining themselves in the threads on low distortion oscillators and discrete (except for a few dual transistors on the same chunk of silicon) op amps.

Others may be like me, catching up on the Blowtorch threads.