9
99-5jamz
Guest
I was sent some audio clips of HD radio. and it sounds like a internet stream. Is that me or is it true?<P ID="signature">______________
[email protected]</P>
[email protected]</P>
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R
RadioDoc
Guest
> I was sent some audio clips of HD radio. and it sounds like
> a internet stream. Is that me or is it true?
>
Were the clips MP3's? Was it AM, or FM? FM (at least done correctly) doesn't sound at all like a stream.
AM does though, at least in my opinion.
If you could provide a few more details, we may be able to come up with some answers.<P ID="signature">______________
</P>
> a internet stream. Is that me or is it true?
>
Were the clips MP3's? Was it AM, or FM? FM (at least done correctly) doesn't sound at all like a stream.
AM does though, at least in my opinion.
If you could provide a few more details, we may be able to come up with some answers.<P ID="signature">______________
</P>
K
k9ez
Guest
> > I was sent some audio clips of HD radio. and it sounds
> like
> > a internet stream. Is that me or is it true?
> >
>
> Were the clips MP3's? Was it AM, or FM? FM (at least done
> correctly) doesn't sound at all like a stream.
>
> AM does though, at least in my opinion.
>
> If you could provide a few more details, we may be able to
> come up with some answers.
>
AM done right sounds decent. We have a Radio Disney in town that sounds GREAT. The CODEC doesnt seem really friendly for voices at this point, as they sound a tad "digital". Music on this Radio Disney outlet sounds great however. Whenever I have demoed the station to people, their jaws literally drop when the HD kicks in.
FM sounds clean to me. Even when running HD2.
As RadioDoc said, if you are getting them via an MP3 you could have bit rates and different CODECs battling and end up with garbage.
> like
> > a internet stream. Is that me or is it true?
> >
>
> Were the clips MP3's? Was it AM, or FM? FM (at least done
> correctly) doesn't sound at all like a stream.
>
> AM does though, at least in my opinion.
>
> If you could provide a few more details, we may be able to
> come up with some answers.
>
AM done right sounds decent. We have a Radio Disney in town that sounds GREAT. The CODEC doesnt seem really friendly for voices at this point, as they sound a tad "digital". Music on this Radio Disney outlet sounds great however. Whenever I have demoed the station to people, their jaws literally drop when the HD kicks in.
FM sounds clean to me. Even when running HD2.
As RadioDoc said, if you are getting them via an MP3 you could have bit rates and different CODECs battling and end up with garbage.
> As RadioDoc said, if you are getting them via an MP3 you
> could have bit rates and different CODECs battling and end
> up with garbage.
I've heard some of these online demos. Clear Channel has one on there new HD site and I think you're probably hearing artifacts in the encoded MP3.
I haven't yet heard HD, so I may be wrong, but that's my educated guess.
Not to hijack this thread, but for those of you that have heard HD, does it sound better then satellite radio? I think satellite radio sounds like an internet stream.<P ID="signature">______________
If you put your mind to it, you can accomplish anything...</P>
> could have bit rates and different CODECs battling and end
> up with garbage.
I've heard some of these online demos. Clear Channel has one on there new HD site and I think you're probably hearing artifacts in the encoded MP3.
I haven't yet heard HD, so I may be wrong, but that's my educated guess.
Not to hijack this thread, but for those of you that have heard HD, does it sound better then satellite radio? I think satellite radio sounds like an internet stream.<P ID="signature">______________
If you put your mind to it, you can accomplish anything...</P>
R
RadioDoc
Guest
> > > I was sent some audio clips of HD radio. and it sounds
> > like
> > > a internet stream. Is that me or is it true?
> > >
> >
> > Were the clips MP3's? Was it AM, or FM? FM (at least
> done
> > correctly) doesn't sound at all like a stream.
> >
> > AM does though, at least in my opinion.
> >
> > If you could provide a few more details, we may be able to
>
> > come up with some answers.
> >
>
>
> AM done right sounds decent. We have a Radio Disney in town
> that sounds GREAT. The CODEC doesnt seem really friendly
> for voices at this point, as they sound a tad "digital".
> Music on this Radio Disney outlet sounds great however.
> Whenever I have demoed the station to people, their jaws
> literally drop when the HD kicks in.
>
> FM sounds clean to me. Even when running HD2.
>
> As RadioDoc said, if you are getting them via an MP3 you
> could have bit rates and different CODECs battling and end
> up with garbage.
>
You're right...I never really put it together until you mentioned it. Music on AM HD sounds great. Talk however seems sort of weak. I wonder how much of that has to do with audio processing and cascading codecs.
It would be interesting to hear what an AM would sound like with uncompressed audio fed directly into the encoder, bypassing any STL hops or bit-rate reduction.
One of the problems that operators will have to watch for is cascading codecs. What happens is the audio can get bit-reduced several times. For example, if your audio is in your automation system in any format other than .wav, you've reduced the bits once. Then, most modern digital studio-to-transmitter links employ some sort of bit-reduction. Finally there is the bit-reduction of the HD codec.
You can recreate the effect by ripping a song off of a CD, then encode it as a high bit-rate MP3. Take that and re-encode it at a lower rate. Take the result and encode it one more time.
It's something that we'll really have to watch as broadcasters. With one of my FM's, the transmitter is at the studio site. All of our audio is loaded as uncompressed .wav's, and there is no data reduction before the HD encoder. It sounds phenominal!
On the other hand, I've heard analog FM's that already suffer from a bit of this even without HD!
As they say...garbage in, garbage out!<P ID="signature">______________
</P>
> > like
> > > a internet stream. Is that me or is it true?
> > >
> >
> > Were the clips MP3's? Was it AM, or FM? FM (at least
> done
> > correctly) doesn't sound at all like a stream.
> >
> > AM does though, at least in my opinion.
> >
> > If you could provide a few more details, we may be able to
>
> > come up with some answers.
> >
>
>
> AM done right sounds decent. We have a Radio Disney in town
> that sounds GREAT. The CODEC doesnt seem really friendly
> for voices at this point, as they sound a tad "digital".
> Music on this Radio Disney outlet sounds great however.
> Whenever I have demoed the station to people, their jaws
> literally drop when the HD kicks in.
>
> FM sounds clean to me. Even when running HD2.
>
> As RadioDoc said, if you are getting them via an MP3 you
> could have bit rates and different CODECs battling and end
> up with garbage.
>
You're right...I never really put it together until you mentioned it. Music on AM HD sounds great. Talk however seems sort of weak. I wonder how much of that has to do with audio processing and cascading codecs.
It would be interesting to hear what an AM would sound like with uncompressed audio fed directly into the encoder, bypassing any STL hops or bit-rate reduction.
One of the problems that operators will have to watch for is cascading codecs. What happens is the audio can get bit-reduced several times. For example, if your audio is in your automation system in any format other than .wav, you've reduced the bits once. Then, most modern digital studio-to-transmitter links employ some sort of bit-reduction. Finally there is the bit-reduction of the HD codec.
You can recreate the effect by ripping a song off of a CD, then encode it as a high bit-rate MP3. Take that and re-encode it at a lower rate. Take the result and encode it one more time.
It's something that we'll really have to watch as broadcasters. With one of my FM's, the transmitter is at the studio site. All of our audio is loaded as uncompressed .wav's, and there is no data reduction before the HD encoder. It sounds phenominal!
On the other hand, I've heard analog FM's that already suffer from a bit of this even without HD!
As they say...garbage in, garbage out!<P ID="signature">______________
</P>
R
RadioDoc
Guest
> > As RadioDoc said, if you are getting them via an MP3 you
> > could have bit rates and different CODECs battling and end
>
> > up with garbage.
>
> I've heard some of these online demos. Clear Channel has
> one on there new HD site and I think you're probably hearing
> artifacts in the encoded MP3.
>
> I haven't yet heard HD, so I may be wrong, but that's my
> educated guess.
>
> Not to hijack this thread, but for those of you that have
> heard HD, does it sound better then satellite radio? I
> think satellite radio sounds like an internet stream.
>
It hands-down beats satellite radio. I have Analog AM-FM/HD AM-FM/Sirius on my car stereo. Sirius (and XM - I have a Sky-Fi as well) can't even come close to touching FM-HD.
Having said that, it very much depends on source material and audio processing.<P ID="signature">______________
</P>
> > could have bit rates and different CODECs battling and end
>
> > up with garbage.
>
> I've heard some of these online demos. Clear Channel has
> one on there new HD site and I think you're probably hearing
> artifacts in the encoded MP3.
>
> I haven't yet heard HD, so I may be wrong, but that's my
> educated guess.
>
> Not to hijack this thread, but for those of you that have
> heard HD, does it sound better then satellite radio? I
> think satellite radio sounds like an internet stream.
>
It hands-down beats satellite radio. I have Analog AM-FM/HD AM-FM/Sirius on my car stereo. Sirius (and XM - I have a Sky-Fi as well) can't even come close to touching FM-HD.
Having said that, it very much depends on source material and audio processing.<P ID="signature">______________
</P>
> It hands-down beats satellite radio. I have Analog AM-FM/HD
> AM-FM/Sirius on my car stereo. Sirius (and XM - I have a
> Sky-Fi as well) can't even come close to touching FM-HD.
That is VERY good to hear.
> Having said that, it very much depends on source material
> and audio processing.
Considering that most stations use some form of file compression for there music libraries (5:1 in most cases) it will be very interesting to hear those stations that use an uncompressed source material.
-Enginerd<P ID="signature">______________
If you put your mind to it, you can accomplish anything...</P>
> AM-FM/Sirius on my car stereo. Sirius (and XM - I have a
> Sky-Fi as well) can't even come close to touching FM-HD.
That is VERY good to hear.
> Having said that, it very much depends on source material
> and audio processing.
Considering that most stations use some form of file compression for there music libraries (5:1 in most cases) it will be very interesting to hear those stations that use an uncompressed source material.
-Enginerd<P ID="signature">______________
If you put your mind to it, you can accomplish anything...</P>
K
k9ez
Guest
> > > As RadioDoc said, if you are getting them via an MP3 you
>
> > > could have bit rates and different CODECs battling and
> end
> >
> > > up with garbage.
> >
> > I've heard some of these online demos. Clear Channel has
> > one on there new HD site and I think you're probably
> hearing
> > artifacts in the encoded MP3.
> >
> > I haven't yet heard HD, so I may be wrong, but that's my
> > educated guess.
> >
> > Not to hijack this thread, but for those of you that have
> > heard HD, does it sound better then satellite radio? I
> > think satellite radio sounds like an internet stream.
> >
>
> It hands-down beats satellite radio. I have Analog AM-FM/HD
> AM-FM/Sirius on my car stereo. Sirius (and XM - I have a
> Sky-Fi as well) can't even come close to touching FM-HD.
>
> Having said that, it very much depends on source material
> and audio processing.
>
To give you a better understanding.... Sat radio sounds like AM HD to me. Just about the same qualities.
So FM HD takes it much further. Even running multicasting it hold the sound quality rather nicely. It is really surprising how good of audio you can get out of that stream. Some people say that they expect it to sound like an internet stream at the same rate. I can certainly tell you it doesnt equate!
>
> > > could have bit rates and different CODECs battling and
> end
> >
> > > up with garbage.
> >
> > I've heard some of these online demos. Clear Channel has
> > one on there new HD site and I think you're probably
> hearing
> > artifacts in the encoded MP3.
> >
> > I haven't yet heard HD, so I may be wrong, but that's my
> > educated guess.
> >
> > Not to hijack this thread, but for those of you that have
> > heard HD, does it sound better then satellite radio? I
> > think satellite radio sounds like an internet stream.
> >
>
> It hands-down beats satellite radio. I have Analog AM-FM/HD
> AM-FM/Sirius on my car stereo. Sirius (and XM - I have a
> Sky-Fi as well) can't even come close to touching FM-HD.
>
> Having said that, it very much depends on source material
> and audio processing.
>
To give you a better understanding.... Sat radio sounds like AM HD to me. Just about the same qualities.
So FM HD takes it much further. Even running multicasting it hold the sound quality rather nicely. It is really surprising how good of audio you can get out of that stream. Some people say that they expect it to sound like an internet stream at the same rate. I can certainly tell you it doesnt equate!
> > Having said that, it very much depends on source material
> > and audio processing.
>
> Considering that most stations use some form of file
> compression for there music libraries (5:1 in most cases) it
> will be very interesting to hear those stations that use an
> uncompressed source material.
>
> -Enginerd
>
There is some music service offering uncompressed audio for automation systems...I don't recall the name but it was something like uncompressedmusic.com
Didn't seem too trustworthy, IMO. Not to mention that the music was only compatible with about 2 automation systems.
As far as studio to tower site communications, I had suspected that would be the fly in the HD ointment. Wouldn't you want 3 seperate feeds going into IBOC? Meaning 3 T1 lines or whatnot?
> > and audio processing.
>
> Considering that most stations use some form of file
> compression for there music libraries (5:1 in most cases) it
> will be very interesting to hear those stations that use an
> uncompressed source material.
>
> -Enginerd
>
There is some music service offering uncompressed audio for automation systems...I don't recall the name but it was something like uncompressedmusic.com
Didn't seem too trustworthy, IMO. Not to mention that the music was only compatible with about 2 automation systems.
As far as studio to tower site communications, I had suspected that would be the fly in the HD ointment. Wouldn't you want 3 seperate feeds going into IBOC? Meaning 3 T1 lines or whatnot?
R
RadioDoc
Guest
> > > Having said that, it very much depends on source
> material
> > > and audio processing.
> >
> > Considering that most stations use some form of file
> > compression for there music libraries (5:1 in most cases)
> it
> > will be very interesting to hear those stations that use
> an
> > uncompressed source material.
> >
> > -Enginerd
> >
> There is some music service offering uncompressed audio for
> automation systems...I don't recall the name but it was
> something like uncompressedmusic.com
>
> Didn't seem too trustworthy, IMO. Not to mention that the
> music was only compatible with about 2 automation systems.
>
> As far as studio to tower site communications, I had
> suspected that would be the fly in the HD ointment.
> Wouldn't you want 3 seperate feeds going into IBOC? Meaning
> 3 T1 lines or whatnot?
>
Sure, in a perfect world, we'd love a big fat pipe! In reality, however, we'll be squeezing 5 gallons of water into a 1 gallon pail. There are a few RF products, mostly in unlicensed spectrum, that provide the needed bandwidth.<P ID="signature">______________
</P>
> material
> > > and audio processing.
> >
> > Considering that most stations use some form of file
> > compression for there music libraries (5:1 in most cases)
> it
> > will be very interesting to hear those stations that use
> an
> > uncompressed source material.
> >
> > -Enginerd
> >
> There is some music service offering uncompressed audio for
> automation systems...I don't recall the name but it was
> something like uncompressedmusic.com
>
> Didn't seem too trustworthy, IMO. Not to mention that the
> music was only compatible with about 2 automation systems.
>
> As far as studio to tower site communications, I had
> suspected that would be the fly in the HD ointment.
> Wouldn't you want 3 seperate feeds going into IBOC? Meaning
> 3 T1 lines or whatnot?
>
Sure, in a perfect world, we'd love a big fat pipe! In reality, however, we'll be squeezing 5 gallons of water into a 1 gallon pail. There are a few RF products, mostly in unlicensed spectrum, that provide the needed bandwidth.<P ID="signature">______________
</P>
> As far as studio to tower site communications, I had
> suspected that would be the fly in the HD ointment.
> Wouldn't you want 3 seperate feeds going into IBOC? Meaning
> 3 T1 lines or whatnot?
Yeah it would seem that way...
P2P T1 lines are what most major market stations are using however I'm curious as what they are using to back up those lease lines.
I believe the Intraplex units (on each end of the T1) allow you to parcel out the bandwidth of a single T1 better perhaps giving you the ability to send 4 channels of audio (not sure what quality - I'll let someone else comment on Intraplex since I don't have much experience with them), but I can tell you that Moseley's P2P T1 products fall short in my opinion as far as flexibilty for HD.
Consider the following. When I worked for CC, we had a P2P T1 (main hauler) for audio 2-22khz channels send, 2-22khz channels rec. We then had a 900Mhz radio link with Moseley Starlink's at both ends to pass AES audio for the back up airchain. Ok, that's fine and dandy for the HD-1 channel and the analog carrier, but what about back up solutions for the HD side channels? There isn't enough spectrum in the standard 900 band to allow for this? Curious what some of these engineers have done in these markets for backup.
-Enginerd<P ID="signature">______________
If you put your mind to it, you can accomplish anything...</P>
> suspected that would be the fly in the HD ointment.
> Wouldn't you want 3 seperate feeds going into IBOC? Meaning
> 3 T1 lines or whatnot?
Yeah it would seem that way...
P2P T1 lines are what most major market stations are using however I'm curious as what they are using to back up those lease lines.
I believe the Intraplex units (on each end of the T1) allow you to parcel out the bandwidth of a single T1 better perhaps giving you the ability to send 4 channels of audio (not sure what quality - I'll let someone else comment on Intraplex since I don't have much experience with them), but I can tell you that Moseley's P2P T1 products fall short in my opinion as far as flexibilty for HD.
Consider the following. When I worked for CC, we had a P2P T1 (main hauler) for audio 2-22khz channels send, 2-22khz channels rec. We then had a 900Mhz radio link with Moseley Starlink's at both ends to pass AES audio for the back up airchain. Ok, that's fine and dandy for the HD-1 channel and the analog carrier, but what about back up solutions for the HD side channels? There isn't enough spectrum in the standard 900 band to allow for this? Curious what some of these engineers have done in these markets for backup.
-Enginerd<P ID="signature">______________
If you put your mind to it, you can accomplish anything...</P>
J
joshleblanc
Guest
Since most of these HD2 stations are automated jukeboxes, why not just stick a box (PC) with the music and automation software out at the tower site? Set it up to allow remote control via dialup or other basic means if necessary to update music, scheduling, or ect. This eliminates the STL bandwith problem.
> Since most of these HD2 stations are automated jukeboxes,
> why not just stick a box (PC) with the music and automation
> software out at the tower site? Set it up to allow remote
> control via dialup or other basic means if necessary to
> update music, scheduling, or ect. This eliminates the STL
> bandwith problem.
>
I once spoke with another engineer about this exact idea. A fully VT'ed station. All you'd need is a T1 or DSL out to the site. Then you'd locate the automation AT the transmitter site. If you had a T1 out to the site you could even use that for music, VT and log transfer with NO problems.
It's not a bad idea, just limits you if you ever want to do more with the side channels.
-Enginerd<P ID="signature">______________
If you put your mind to it, you can accomplish anything...</P>
> why not just stick a box (PC) with the music and automation
> software out at the tower site? Set it up to allow remote
> control via dialup or other basic means if necessary to
> update music, scheduling, or ect. This eliminates the STL
> bandwith problem.
>
I once spoke with another engineer about this exact idea. A fully VT'ed station. All you'd need is a T1 or DSL out to the site. Then you'd locate the automation AT the transmitter site. If you had a T1 out to the site you could even use that for music, VT and log transfer with NO problems.
It's not a bad idea, just limits you if you ever want to do more with the side channels.
-Enginerd<P ID="signature">______________
If you put your mind to it, you can accomplish anything...</P>
B
bossmsx
Guest
AM vs. FM (and FM at varying bitrates)
What I heard in Philly was this...When WPEN was still playing music, depending on the song the codec either really sounded great, or it went downhill...Some songs, like "Blue on Blue" by Vinton trashed the sound...OTOH, "You Can't Hurry Love" was almost indistinguishable from FM and probably better....Probably instruments..Bear in mind, also the frequency response is higher than analog FM this helps in one sense, whether or not it 'sounds' better, and the Stereo separation is well nigh out of this world, be it AM OR FM..Leonard Kahn actually uses this in his arguments against IBOC, that the dbs of separation are more than the human skull (or ears?) can discern, lol, and you can tell it's so great that it actually exceeds anything you've experienced in a while, at least that I can tell.
FM, I could tell a difference by the bitrate...At the time, BEN FM had not yet started multicasting and was running the full 96kbps that stations that only run one stream run...Tremendous sound..The Yamaha I had starts you off analog and 'blends in' to Stereo Digital, and that was just amazing...I would almost say the HDC codec at 96kbps was better on FM than the MP2 codec used by DAB/Eureka-147 that I heard at 192kbps (or 224) in Toronto, but the radio I had in Toronto was a cheap Perstel "Walkman" type, and the one in Philly was a Yamaha home theater unit, so that might be the case instead. WRDW-FM had 3 different streams and you could tell the compromise but probably was a case of 'some ears yes, some ears no', and still not the shrill 'aluminum foil'-ness that I heard on XM, or worse, Sirius.
Another thing is the noise level is well, there is no noise so what you have as hiss on analog is pure, I mean, pure silence on digital...Like you don't know silence.
What I heard in Philly was this...When WPEN was still playing music, depending on the song the codec either really sounded great, or it went downhill...Some songs, like "Blue on Blue" by Vinton trashed the sound...OTOH, "You Can't Hurry Love" was almost indistinguishable from FM and probably better....Probably instruments..Bear in mind, also the frequency response is higher than analog FM this helps in one sense, whether or not it 'sounds' better, and the Stereo separation is well nigh out of this world, be it AM OR FM..Leonard Kahn actually uses this in his arguments against IBOC, that the dbs of separation are more than the human skull (or ears?) can discern, lol, and you can tell it's so great that it actually exceeds anything you've experienced in a while, at least that I can tell.
FM, I could tell a difference by the bitrate...At the time, BEN FM had not yet started multicasting and was running the full 96kbps that stations that only run one stream run...Tremendous sound..The Yamaha I had starts you off analog and 'blends in' to Stereo Digital, and that was just amazing...I would almost say the HDC codec at 96kbps was better on FM than the MP2 codec used by DAB/Eureka-147 that I heard at 192kbps (or 224) in Toronto, but the radio I had in Toronto was a cheap Perstel "Walkman" type, and the one in Philly was a Yamaha home theater unit, so that might be the case instead. WRDW-FM had 3 different streams and you could tell the compromise but probably was a case of 'some ears yes, some ears no', and still not the shrill 'aluminum foil'-ness that I heard on XM, or worse, Sirius.
Another thing is the noise level is well, there is no noise so what you have as hiss on analog is pure, I mean, pure silence on digital...Like you don't know silence.
R
RadioDoc
Guest
> > As far as studio to tower site communications, I had
> > suspected that would be the fly in the HD ointment.
> > Wouldn't you want 3 seperate feeds going into IBOC?
> Meaning
> > 3 T1 lines or whatnot?
>
> Yeah it would seem that way...
>
> P2P T1 lines are what most major market stations are using
> however I'm curious as what they are using to back up those
> lease lines.
>
> I believe the Intraplex units (on each end of the T1) allow
> you to parcel out the bandwidth of a single T1 better
> perhaps giving you the ability to send 4 channels of audio
> (not sure what quality - I'll let someone else comment on
> Intraplex since I don't have much experience with them), but
> I can tell you that Moseley's P2P T1 products fall short in
> my opinion as far as flexibilty for HD.
>
> Consider the following. When I worked for CC, we had a P2P
> T1 (main hauler) for audio 2-22khz channels send, 2-22khz
> channels rec. We then had a 900Mhz radio link with Moseley
> Starlink's at both ends to pass AES audio for the back up
> airchain. Ok, that's fine and dandy for the HD-1 channel
> and the analog carrier, but what about back up solutions for
> the HD side channels? There isn't enough spectrum in the
> standard 900 band to allow for this? Curious what some of
> these engineers have done in these markets for backup.
>
> -Enginerd
>
I use a Moseley DSP-6000 to backup my Intraplex. Both boxes use data reduction to send 4 channels, though it's not objectionable.
Moseley Starlinks can do 4 channels as well. All in a standard 900MHz BAS frequency. As for three sets of channels...still not much available!<P ID="signature">______________
</P>
> > suspected that would be the fly in the HD ointment.
> > Wouldn't you want 3 seperate feeds going into IBOC?
> Meaning
> > 3 T1 lines or whatnot?
>
> Yeah it would seem that way...
>
> P2P T1 lines are what most major market stations are using
> however I'm curious as what they are using to back up those
> lease lines.
>
> I believe the Intraplex units (on each end of the T1) allow
> you to parcel out the bandwidth of a single T1 better
> perhaps giving you the ability to send 4 channels of audio
> (not sure what quality - I'll let someone else comment on
> Intraplex since I don't have much experience with them), but
> I can tell you that Moseley's P2P T1 products fall short in
> my opinion as far as flexibilty for HD.
>
> Consider the following. When I worked for CC, we had a P2P
> T1 (main hauler) for audio 2-22khz channels send, 2-22khz
> channels rec. We then had a 900Mhz radio link with Moseley
> Starlink's at both ends to pass AES audio for the back up
> airchain. Ok, that's fine and dandy for the HD-1 channel
> and the analog carrier, but what about back up solutions for
> the HD side channels? There isn't enough spectrum in the
> standard 900 band to allow for this? Curious what some of
> these engineers have done in these markets for backup.
>
> -Enginerd
>
I use a Moseley DSP-6000 to backup my Intraplex. Both boxes use data reduction to send 4 channels, though it's not objectionable.
Moseley Starlinks can do 4 channels as well. All in a standard 900MHz BAS frequency. As for three sets of channels...still not much available!<P ID="signature">______________
</P>
> I use a Moseley DSP-6000 to backup my Intraplex. Both boxes
> use data reduction to send 4 channels, though it's not
> objectionable.
>
> Moseley Starlinks can do 4 channels as well. All in a
> standard 900MHz BAS frequency. As for three sets of
> channels...still not much available!
>
Doc,
Very good point! You are correct that Starlink's and DSP-6000's WILL do 4 channels. Any stations using DSP's or a Starlink for a double hop don't have that luxury though(as CC Sac does). I'm sure many stations across the country suffer that similar fate.
-Enginerd<P ID="signature">______________
If you put your mind to it, you can accomplish anything...</P>
> use data reduction to send 4 channels, though it's not
> objectionable.
>
> Moseley Starlinks can do 4 channels as well. All in a
> standard 900MHz BAS frequency. As for three sets of
> channels...still not much available!
>
Doc,
Very good point! You are correct that Starlink's and DSP-6000's WILL do 4 channels. Any stations using DSP's or a Starlink for a double hop don't have that luxury though(as CC Sac does). I'm sure many stations across the country suffer that similar fate.
-Enginerd<P ID="signature">______________
If you put your mind to it, you can accomplish anything...</P>
> As for three sets of channels...still not much available!
I'm curious, with the Intraplex, how many channels and what available bandwidth do you have for audio? I assume by your last post that 4 channels is not an issue. What will it pass? How many Khz?
<P ID="signature">______________
If you put your mind to it, you can accomplish anything...</P>
I'm curious, with the Intraplex, how many channels and what available bandwidth do you have for audio? I assume by your last post that 4 channels is not an issue. What will it pass? How many Khz?
<P ID="signature">______________
If you put your mind to it, you can accomplish anything...</P>
R
RadioDoc
Guest
> > As for three sets of channels...still not much available!
>
> I'm curious, with the Intraplex, how many channels and what
> available bandwidth do you have for audio? I assume by your
> last post that 4 channels is not an issue. What will it
> pass? How many Khz?
>
The Intraplex will pass four discreet 15KHz channels, or two stereo "pairs". I don't know if you can pass more at a lower quality or not, though.<P ID="signature">______________
</P>
>
> I'm curious, with the Intraplex, how many channels and what
> available bandwidth do you have for audio? I assume by your
> last post that 4 channels is not an issue. What will it
> pass? How many Khz?
>
The Intraplex will pass four discreet 15KHz channels, or two stereo "pairs". I don't know if you can pass more at a lower quality or not, though.<P ID="signature">______________
</P>
R
RadioDoc
Guest
> > I use a Moseley DSP-6000 to backup my Intraplex. Both
> boxes
> > use data reduction to send 4 channels, though it's not
> > objectionable.
> >
> > Moseley Starlinks can do 4 channels as well. All in a
> > standard 900MHz BAS frequency. As for three sets of
> > channels...still not much available!
> >
>
> Doc,
>
> Very good point! You are correct that Starlink's and
> DSP-6000's WILL do 4 channels. Any stations using DSP's or
> a Starlink for a double hop don't have that luxury though(as
> CC Sac does). I'm sure many stations across the country
> suffer that similar fate.
>
> -Enginerd
>
Actually, you could. I did a double hop with DSP-6000's by just looping the analog outs to the ins at the relay point. You really can't do that more than once, though! Of course, that's not a great way to do it, but when you need to make it happen...
<P ID="signature">______________
</P>
> boxes
> > use data reduction to send 4 channels, though it's not
> > objectionable.
> >
> > Moseley Starlinks can do 4 channels as well. All in a
> > standard 900MHz BAS frequency. As for three sets of
> > channels...still not much available!
> >
>
> Doc,
>
> Very good point! You are correct that Starlink's and
> DSP-6000's WILL do 4 channels. Any stations using DSP's or
> a Starlink for a double hop don't have that luxury though(as
> CC Sac does). I'm sure many stations across the country
> suffer that similar fate.
>
> -Enginerd
>
Actually, you could. I did a double hop with DSP-6000's by just looping the analog outs to the ins at the relay point. You really can't do that more than once, though! Of course, that's not a great way to do it, but when you need to make it happen...
<P ID="signature">______________</P>
K
k9ez
Guest
> > As far as studio to tower site communications, I had
> > suspected that would be the fly in the HD ointment.
> > Wouldn't you want 3 seperate feeds going into IBOC?
> Meaning
> > 3 T1 lines or whatnot?
>
> Yeah it would seem that way...
>
> P2P T1 lines are what most major market stations are using
> however I'm curious as what they are using to back up those
> lease lines.
>
> I believe the Intraplex units (on each end of the T1) allow
> you to parcel out the bandwidth of a single T1 better
> perhaps giving you the ability to send 4 channels of audio
> (not sure what quality - I'll let someone else comment on
> Intraplex since I don't have much experience with them), but
> I can tell you that Moseley's P2P T1 products fall short in
> my opinion as far as flexibilty for HD.
>
> Consider the following. When I worked for CC, we had a P2P
> T1 (main hauler) for audio 2-22khz channels send, 2-22khz
> channels rec. We then had a 900Mhz radio link with Moseley
> Starlink's at both ends to pass AES audio for the back up
> airchain. Ok, that's fine and dandy for the HD-1 channel
> and the analog carrier, but what about back up solutions for
> the HD side channels? There isn't enough spectrum in the
> standard 900 band to allow for this? Curious what some of
> these engineers have done in these markets for backup.
>
> -Enginerd
>
Remember that the HD2 stream is just that. A data stream. So you are not sending the HD2 out to the transmitter as discreet audio channels, but as a high end data stream.
> > suspected that would be the fly in the HD ointment.
> > Wouldn't you want 3 seperate feeds going into IBOC?
> Meaning
> > 3 T1 lines or whatnot?
>
> Yeah it would seem that way...
>
> P2P T1 lines are what most major market stations are using
> however I'm curious as what they are using to back up those
> lease lines.
>
> I believe the Intraplex units (on each end of the T1) allow
> you to parcel out the bandwidth of a single T1 better
> perhaps giving you the ability to send 4 channels of audio
> (not sure what quality - I'll let someone else comment on
> Intraplex since I don't have much experience with them), but
> I can tell you that Moseley's P2P T1 products fall short in
> my opinion as far as flexibilty for HD.
>
> Consider the following. When I worked for CC, we had a P2P
> T1 (main hauler) for audio 2-22khz channels send, 2-22khz
> channels rec. We then had a 900Mhz radio link with Moseley
> Starlink's at both ends to pass AES audio for the back up
> airchain. Ok, that's fine and dandy for the HD-1 channel
> and the analog carrier, but what about back up solutions for
> the HD side channels? There isn't enough spectrum in the
> standard 900 band to allow for this? Curious what some of
> these engineers have done in these markets for backup.
>
> -Enginerd
>
Remember that the HD2 stream is just that. A data stream. So you are not sending the HD2 out to the transmitter as discreet audio channels, but as a high end data stream.
- Status