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Separating AM from FM HD

Re: All right, I have had enough of this.

> > > Thats exactly what most of us arew doing with HD Radio.
> >
> > Analog AM radio, analog FM radio, and Compact Discs were
> all
> > very dynamic when first introduced, with little or no
> > compression/limiting/clipping used to increase loudness...
>
> > but over time, all of these media have become increasingly
>
> > over-processed and decreasingly "hi-fi". The same exact
> > thing will happen to any form of digital terrestrial radio
>
> > -- because while you can change the technology, you can't
> > change the mentality that "louder is better". Even XM and
>
> > Sirius are both more highly-processed than they really
> need
> > to be, despite the total lack of the kind of competitive
> > rivalry (between their own channels) which has led to the
> > AM/FM/CD loudness wars.
> >
>
> I would agree that some CDs and audio from studios come to
> broadcasters too processed. I ahev had a number of
> conversations with our people about how we can convince the
> studios to give us more of a raw cut. Some of the
> processing (Nashville in particular IMHO) that comes off of
> these music pieces plays havoc with the processing we are
> trying to do.
>
> That beign said, it is still important for a radio station
> to add some processing. Your "typical" listener is
> listening in an evnviroment that usually has ambient noise.
> ie a car. If you dont process you will have too many peaks
> and valleys where the listener will need to turn the volume
> up and down. A fine example is NPRs Whadya Know? show.
> When I listen, I find that I am turning the volume up and
> down. It becomes quite irritating!
>
> Yes I have PDs that want us to be at least competitve
> loudness wise, but we are not always the loudest in the
> market. We try for the fine line of decent loudness and
> good sound.
>
> On HD1 and 2 I am running processing that is equivalent to a
> "Classical" setting. But I do a little tweaking on the EQ.
> It provides and minimal compression setting. giving some
> leveling, but not processing to the teeth like some analog
> stations can. That over processing is like fingernails on
> the chalk board.
>
> Funny with all of this discussion about processing, I truly
> wonder how many of the "average listener" really notices the
> difference.
>

I think processing is a lot like good seasoning. In the right amount, it can make your dish "perfect". Too much and it tastes awful!

:)<P ID="signature">______________
</P>
 
Re: All right, I have had enough of this.

> > radio. Even at the full bandwidth available on FM IBOC,
> > there is no CD quality. You want CD quality?? Cut back
> the
> > processors so they arent clipping so hard to make them
> > loud.....
>
>
> Thats exactly what most of us arew doing with HD Radio.

Then please send your people to my market. Within 100 miles, when I had the Kenwood tuner, only WBOS, Boston appeared to be processing separately. The rest sounded exactly the same in digital as analog when the mode switched.

According to Bob Orban, San Francisco has some dual processed stations that take advantage of the 20 KHz without preemphasis. I almost expect him to walk into a few stations with his processor just so he can hear decent audio on his BA receiver.

Rich
 
Re: All right, I have had enough of this.

> Funny with all of this discussion about processing, I truly
> wonder how many of the "average listener" really notices the
> difference.

Differences in audio processing are mostly perceived subconsciously, unless there is a drastic differences in the sound of each station. Some people are really "tone-deaf" when it comes to audio (I had one friend who simply could not understand the concept of "bass" and "treble"; as I moved the knobs on my amplifier back and forth to demonstrate, he could only identify the sound getting "louder" or "softer"; he was unable to distinguish the change in tonality!)... while other people are consciously able to distinguish differences in loudness as little as +/- 0.5 dB.

But in this case, even if you have the best audio processing in the world, the benefits of that get thrown out the window when you factor in the psychoacoustic effects of IBOC's audio codec artifacts, especially on the low-bitrate FM "HD2" and main AM digital channels. Again, it's very subjective; to me, IBOC's "simulated treble" (also heard on XM, which uses a very similar codec) is like the sound of fingernails scratching on a chalkboard, while to other people, they don't even notice it at all. In fact, I literally got a headache from listening to XM in a coworker's car... with tweeters aimed right at my face, the codec artifacts were magnified and became extremely annoying, to the point where I simply could not enjoy the programming, even if they played all my favorite songs.
<P ID="signature">______________
It's a common mistake to not use punctuation in its proper form.
<a target="_blank" href=http://www.cgl.uwaterloo.ca/~csk/its.html>Be kind to your friend, the apostrophe.</a></P>
 
Re: All right, I have had enough of this.

>
> But in this case, even if you have the best audio processing
> in the world, the benefits of that get thrown out the window
> when you factor in the psychoacoustic effects of IBOC's
> audio codec artifacts, especially on the low-bitrate FM
> "HD2" and main AM digital channels. Again, it's very
> subjective; to me, IBOC's "simulated treble" (also heard on
> XM, which uses a very similar codec) is like the sound of
> fingernails scratching on a chalkboard, while to other
> people, they don't even notice it at all. In fact, I
> literally got a headache from listening to XM in a
> coworker's car... with tweeters aimed right at my face, the
> codec artifacts were magnified and became extremely
> annoying, to the point where I simply could not enjoy the
> programming, even if they played all my favorite songs.
>

Although I personally haven't heard the artifacts you're talking about on HD, I certainly have heard it on XM and you're right...it's awful. I ended up cancelling my subscription because listening gave me a headache!<P ID="signature">______________
</P>
 
Tell me ain't so!

In fact, I
> literally got a headache from listening to XM in a
> coworker's car... with tweeters aimed right at my face, the
> codec artifacts were magnified and became extremely
> annoying, to the point where I simply could not enjoy the
> programming, even if they played all my favorite songs.
>
When the PD of one of ur FM's had me listen to his XM, I got a massive headache withing 15 minutes. He then switched to some talk station (I don't recall now which one and it doesn't matter) it was the worse coding I have ever heard. I said to him, "you have the nerve to itch to me about using our GSM Matrix live on air on your station and you listen to this crap"? It kills how everytime one of our salepeople get a Sat. radio they want me listen to it to hear how great it sounds...I just laugh and point out how awful it is then make them listen to ours, to which the usually get pissed.
So please, please, tell me that HD does NOT sound like XM or Sirius! My only experience with it was 3 years ago at NAB and was horrible at best but I will not judge HD because many things have changed since then.
 
Re: Tell me ain't so!

> In fact, I
> > literally got a headache from listening to XM in a
> > coworker's car... with tweeters aimed right at my face,
> the
> > codec artifacts were magnified and became extremely
> > annoying, to the point where I simply could not enjoy the
> > programming, even if they played all my favorite songs.
> >
> When the PD of one of ur FM's had me listen to his XM, I got
> a massive headache withing 15 minutes. He then switched to
> some talk station (I don't recall now which one and it
> doesn't matter) it was the worse coding I have ever heard. I
> said to him, "you have the nerve to itch to me about using
> our GSM Matrix live on air on your station and you listen to
> this crap"? It kills how everytime one of our salepeople get
> a Sat. radio they want me listen to it to hear how great it
> sounds...I just laugh and point out how awful it is then
> make them listen to ours, to which the usually get pissed.
> So please, please, tell me that HD does NOT sound like XM or
> Sirius! My only experience with it was 3 years ago at NAB
> and was horrible at best but I will not judge HD because
> many things have changed since then.
>

From what I've heard, HD Radio sounds WAY better than satellite radio.
<P ID="signature">______________
16-year-old radio geek.</P>
 
Re: Tell me ain't so!

> From what I've heard, HD Radio sounds WAY better than
> satellite radio.

XM and HD Radio both use essentially the same codec (aacPlus with SBR -- a.k.a. "simulated treble"). The exact bitrate of the XM music channels is unknown, but it was rumored to be around 48 kbps when the service was first launched, and now that they've added more channels, it's probably around 40 kbps for the music channels and anywhere from 20 to 32 kbps for the talk channels. In comparison, AM IBOC is 36 kbps, while FM IBOC is a maximum of 96 kbps, split up between however many channels the station chooses to broadcast (typical splits are 64 + 32 kbps or 48 + 48 kbps for two channels, and 48 + 32 + 32 kbps for three channels).

IMO, Sirius does a better job of covering up its codec artifacts. It limits the audio response to a maximum of 12 kHz and the stereo separation to a maximum of 1.7 kHz, so the resulting audio is less crisp and often doesn't have very distinct stereo imaging, but is cleaner and more natural-sounding than XM's crisp but heavily-artifacted treble response. <a target="_blank" href=http://www.radio-info.com/mods/board?Post=659429&Board=sirius>Click here</a> for more info and some Sirius and IBOC audio samples to download and listen to on your PC.
<P ID="signature">______________
It's a common mistake to not use punctuation in its proper form.
<a target="_blank" href=http://www.cgl.uwaterloo.ca/~csk/its.html>Be kind to your friend, the apostrophe.</a></P>
 
Re: Tell me ain't so!

> > In fact, I
> > > literally got a headache from listening to XM in a
> > > coworker's car... with tweeters aimed right at my face,
> > the
> > > codec artifacts were magnified and became extremely
> > > annoying, to the point where I simply could not enjoy
> the
> > > programming, even if they played all my favorite songs.
> > >
> > When the PD of one of ur FM's had me listen to his XM, I
> got
> > a massive headache withing 15 minutes. He then switched to
>
> > some talk station (I don't recall now which one and it
> > doesn't matter) it was the worse coding I have ever heard.
> I
> > said to him, "you have the nerve to itch to me about using
>
> > our GSM Matrix live on air on your station and you listen
> to
> > this crap"? It kills how everytime one of our salepeople
> get
> > a Sat. radio they want me listen to it to hear how great
> it
> > sounds...I just laugh and point out how awful it is then
> > make them listen to ours, to which the usually get pissed.
>
> > So please, please, tell me that HD does NOT sound like XM
> or
> > Sirius! My only experience with it was 3 years ago at NAB
> > and was horrible at best but I will not judge HD because
> > many things have changed since then.
> >
>
> From what I've heard, HD Radio sounds WAY better than
> satellite radio.
>

Trust me it does! You sound hear stations like WNUA Chicagos HD2 Straight Jazz! You will be very happy!

Sat radio is fingrnails on teh chalkboard
 
Re: Tell me ain't so!

> XM and HD Radio both use essentially the same codec (aacPlus
> with SBR -- a.k.a. "simulated treble"). The exact bitrate
> of the XM music channels is unknown, but it was rumored to
> be around 48 kbps when the service was first launched, and
> now that they've added more channels, it's probably around
> 40 kbps for the music channels and anywhere from 20 to 32
> kbps for the talk channels. In comparison, AM IBOC is 36
> kbps, while FM IBOC is a maximum of 96 kbps, split up
> between however many channels the station chooses to
> broadcast (typical splits are 64 + 32 kbps or 48 + 48 kbps
> for two channels, and 48 + 32 + 32 kbps for three channels).

Thanks for the info on the codecs. It explains what I was hearing, but I didn't know why I was hearing it. I agree that I like the sound quality on Sirius better than XM but I'm not wild about either one. I chose Sirius for my car, but not because of the audio quality. It was because they had more channels that appealed to me. I have found that it takes a few minutes of listening to desensitize my ears, before it begins to sound decent. Psychoaccoustics is an amazing thing.
 
Re: Tell me ain't so!

> > From what I've heard, HD Radio sounds WAY better than
> > satellite radio.
>
> XM and HD Radio both use essentially the same codec (aacPlus
> with SBR -- a.k.a. "simulated treble"). The exact bitrate
> of the XM music channels is unknown, but it was rumored to
> be around 48 kbps when the service was first launched, and
> now that they've added more channels, it's probably around
> 40 kbps for the music channels and anywhere from 20 to 32
> kbps for the talk channels. In comparison, AM IBOC is 36
> kbps, while FM IBOC is a maximum of 96 kbps, split up
> between however many channels the station chooses to
> broadcast (typical splits are 64 + 32 kbps or 48 + 48 kbps
> for two channels, and 48 + 32 + 32 kbps for three channels).
>
>
> IMO, Sirius does a better job of covering up its codec
> artifacts. It limits the audio response to a maximum of 12
> kHz and the stereo separation to a maximum of 1.7 kHz, so
> the resulting audio is less crisp and often doesn't have
> very distinct stereo imaging, but is cleaner and more
> natural-sounding than XM's crisp but heavily-artifacted
> treble response. Click here for more info and some Sirius
> and IBOC audio samples to download and listen to on your PC.
>

I really prefer Sirius's audio to XM's. I find it a lot easier to listen to long term than XM.<P ID="signature">______________
</P>
 
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