That link is confusing.
For my 2012 300, it says Sirius. For a 2018 300, it says SiriusXM. Does that mean the 2018 has both? Only XM as Scott suggests?
Actual technology used on SiriusXM radios
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That link is confusing.
For my 2012 300, it says Sirius. For a 2018 300, it says SiriusXM. Does that mean the 2018 has both? Only XM as Scott suggests?
If it says its using SiriusXM then it is using XM Technology.
Note that a lot of radios themselves (such as my 2012 Chrysler), as opposed to the website, say they are "SiriusXM". But I cannot tune to channel 300. I think SiriusXM is intentionally trying to confuse people.
So- is this (((SXM))) the same moniker as SiriusXM? 2016 Outback.
I can tune in 300 Celebrate! so I guess it’s XM? But it cuts in and out, and sometimes says No Signal. But I’m parked under a tree and a storm is approaching.
Actually sorry for it to be XM. AQ is just not so good. Harman Kardon.
Yes that is XM. Celebrate is only on XM and only with newer radios. (XM 2.0)
I think I can help everyone out on this, although it's been a while since I researched it and things may have changed some -- I've pretty much given up on satellite radio due to bad programming choices and crappy audio quality -- I was one of the very early customers of Sirius; my account number is still 5 digits including a leading 0, had some friends who worked there in the early days, and used to keep up with the industry.
The general rule of thumb that has always stuck is that XM has better audio quality, while Sirius has better reception. XM also has smaller radios and a more efficient chipset which is cheaper, while Sirius has a much more complex chipset due to reasons I'll explain below.
There are a couple major differences between the XM technology and Sirius technology:
First off, there are two satellite radio channels -- the A band and the B band -- both are 12.5 mhz. wide -- XM is A, Sirius is B
The XM platfom uses 2 geostationary satellites at 115* and 85*, plus a terrestrial repeater network. The look angle on these satellites would be the same as aiming a satellite dish for TV; anywhere from 40* to 20* depending where you are -- and the dead spots always stay the same anytime you go to a dead area -- no view of the southern sky or no repeater around? No XM radio. The bandwidth is divided into 1/3, and each 1/3 broadcasts from each source; so all the channels are crammed into a space smaller than one 6 mhz. TV channel; about 4.16 mhz. -- the two satellites plus the repeaters; the satellites and repeaters are slightly off-sync and with error correction, so the receiver can pull a faded signal from another satellite or the repeater if available.
The chipset for XM was reasonably simple, cheap, could be made small, and only had to contend with 3 sources, two of them stationary. In addition, the actual audio encoding technology was software defined and could be -- and has been -- changed, which has allowed many additional channels to be added with the same limited bandwidth. I believe their initial encoding was similar to HD Radio, but over time they have enhanced it and made it more efficient. That is why you need a new radio to pick up these new channels.
The Sirius platform uses 3 satellites in a figure 8 pattern; while 2 are moving overhead at any one time, one is down in South America; as that one moves back up into position, the third one is on it's way south. The benefit to this is that the look angle is much higher -- up to 90* at certain times of the day if you are in the midwest -- but always around 50-60*; that means the reception is much better since there is no "southern sky" issue -- the satellites make a small loop over the midwest in Canada, and then swoop left and right over the US. The reception varies depending on the time of day and your location -- but is generally better than XM. The needed repeaters are staggering -- ~150 or so for Sirius in major cities with skyscrapers or tunnels, vs 1200+ for XM where there are any trees blocking the southern sky. In addition to the 2 moving satellites, they also have a geostationary satellite at 95* which is smack in the middle of the US, as well as the repeater network -- this means that Sirius's signals are split into 1/4 -- all channels are crammed into about 3.12 mhz. of bandwidth -- but because the receiver can pick from 2 moving satellites, a geostationary sat and a repeater network, the reception has less points of failure.
That said, the processing power due to the moving satellites and additional source, made the chipset HUGE -- 8 chips for the first generation units -- Sirius was far behind XM in making small radios... look up Agere Sirius Chipset for more information on Google. It was huge, hot, and made portable Sirius radios unavailable until the 3rd or 4th gen chipset when they shrunk it down to 3 chips -- but even then, my first Sirius portable was gigantic and had large vents on it compared to the tiny XM units. Because the chipset was limited to one suppier -- Agere -- and so complex, Sirius had to delay their launch for some time. Additional chipset suppliers didn't happen until the 4th generation units, when it finally got brought down to two chips. In addition, the encoder was hardware defined to the chip and was called PAC -- Perceptive Audio Coding -- as in, Sirius is still stuck with the same compression since they launched the service. Combined with splitting the bandwidth by an extra source, and being unable to take advantage of newer decoding techology, Sirius audio quality has suffered while they cram more channels on the system. Sirius ideally would have topped out at 60 channels while XM could take 100. As it is, to "match" in the name of the merger, the Sirius platform just gets more and more crammed onto it with the same old encoders, while XM has been able to upgrade over the years. At one point right before the merger, Sirius tried to cram 3 TV channels for "Sirius Backseat TV" into certain Chysler minivans... it KILLED the audio quality... they never recovered because after they killed the TV, they crammed all of the XM channels on.
That said, because both of these systems are some completely incompatible for the reasons listed above, SiriusXM has never been able to standardize on one system -- they still have to maintain one or the other -- and because they are incompatible, have never been able to truly "double their channels" and take advantage of both the A and B bands without duplication. There was one radio that came out that could tune both systems, but it was short lived as an excuse for the merger to go through, and both lineups are pretty much the same with the exception of a few channels.
Eventually they will get to a point with Sirius units where they can turn it off and tell everyone "just upgrade your radio or it goes away on X date" -- but they aren't there yet. As much as I think the Sirius system is superior reception wise, the XM system is so much less complex, cheaper to maintain, requires much less complex and cheaper chipsets, and can take firmware updates for more efficient encoding. Once they do turn off the Sirius satellites, they will be able to use both channels, and will be able to increase the audio quality --- or probably just cram in more channels, or try to do TV again....
N
The general rule of thumb that has always stuck is that XM has better audio quality, while Sirius has better reception. XM also has smaller radios and a more efficient chipset which is cheaper, while Sirius has a much more complex chipset due to reasons I'll explain below.
There are a couple major differences between the XM technology and Sirius technology:
First off, there are two satellite radio channels -- the A band and the B band -- both are 12.5 mhz. wide -- XM is A, Sirius is B
The XM platfom uses 2 geostationary satellites at 115* and 85*, plus a terrestrial repeater network. The look angle on these satellites would be the same as aiming a satellite dish for TV; anywhere from 40* to 20* depending where you are -- and the dead spots always stay the same anytime you go to a dead area -- no view of the southern sky or no repeater around? No XM radio. The bandwidth is divided into 1/3, and each 1/3 broadcasts from each source; so all the channels are crammed into a space smaller than one 6 mhz. TV channel; about 4.16 mhz. -- the two satellites plus the repeaters; the satellites and repeaters are slightly off-sync and with error correction, so the receiver can pull a faded signal from another satellite or the repeater if available.
The chipset for XM was reasonably simple, cheap, could be made small, and only had to contend with 3 sources, two of them stationary. In addition, the actual audio encoding technology was software defined and could be -- and has been -- changed, which has allowed many additional channels to be added with the same limited bandwidth. I believe their initial encoding was similar to HD Radio, but over time they have enhanced it and made it more efficient. That is why you need a new radio to pick up these new channels.
The Sirius platform uses 3 satellites in a figure 8 pattern; while 2 are moving overhead at any one time, one is down in South America; as that one moves back up into position, the third one is on it's way south. The benefit to this is that the look angle is much higher -- up to 90* at certain times of the day if you are in the midwest -- but always around 50-60*; that means the reception is much better since there is no "southern sky" issue -- the satellites make a small loop over the midwest in Canada, and then swoop left and right over the US. The reception varies depending on the time of day and your location -- but is generally better than XM. The needed repeaters are staggering -- ~150 or so for Sirius in major cities with skyscrapers or tunnels, vs 1200+ for XM where there are any trees blocking the southern sky. In addition to the 2 moving satellites, they also have a geostationary satellite at 95* which is smack in the middle of the US, as well as the repeater network -- this means that Sirius's signals are split into 1/4 -- all channels are crammed into about 3.12 mhz. of bandwidth -- but because the receiver can pick from 2 moving satellites, a geostationary sat and a repeater network, the reception has less points of failure.
That said, the processing power due to the moving satellites and additional source, made the chipset HUGE -- 8 chips for the first generation units -- Sirius was far behind XM in making small radios... look up Agere Sirius Chipset for more information on Google. It was huge, hot, and made portable Sirius radios unavailable until the 3rd or 4th gen chipset when they shrunk it down to 3 chips -- but even then, my first Sirius portable was gigantic and had large vents on it compared to the tiny XM units. Because the chipset was limited to one suppier -- Agere -- and so complex, Sirius had to delay their launch for some time. Additional chipset suppliers didn't happen until the 4th generation units, when it finally got brought down to two chips. In addition, the encoder was hardware defined to the chip and was called PAC -- Perceptive Audio Coding -- as in, Sirius is still stuck with the same compression since they launched the service. Combined with splitting the bandwidth by an extra source, and being unable to take advantage of newer decoding techology, Sirius audio quality has suffered while they cram more channels on the system. Sirius ideally would have topped out at 60 channels while XM could take 100. As it is, to "match" in the name of the merger, the Sirius platform just gets more and more crammed onto it with the same old encoders, while XM has been able to upgrade over the years. At one point right before the merger, Sirius tried to cram 3 TV channels for "Sirius Backseat TV" into certain Chysler minivans... it KILLED the audio quality... they never recovered because after they killed the TV, they crammed all of the XM channels on.
That said, because both of these systems are some completely incompatible for the reasons listed above, SiriusXM has never been able to standardize on one system -- they still have to maintain one or the other -- and because they are incompatible, have never been able to truly "double their channels" and take advantage of both the A and B bands without duplication. There was one radio that came out that could tune both systems, but it was short lived as an excuse for the merger to go through, and both lineups are pretty much the same with the exception of a few channels.
Eventually they will get to a point with Sirius units where they can turn it off and tell everyone "just upgrade your radio or it goes away on X date" -- but they aren't there yet. As much as I think the Sirius system is superior reception wise, the XM system is so much less complex, cheaper to maintain, requires much less complex and cheaper chipsets, and can take firmware updates for more efficient encoding. Once they do turn off the Sirius satellites, they will be able to use both channels, and will be able to increase the audio quality --- or probably just cram in more channels, or try to do TV again....
N
But no HEVC equivalent due to limitations in haw far XM radios can be reprogrammed?
Superb post, BTW!
Superb post, BTW!
That’s because Sirius doesn’t have channel 300. As Scott has said only XM has it. That is away to prove which radio you have.
All I can tell you is that Honda, at least circa 2013, used XM. The best way to tell used to be where certain channels were on your receiver. For instance, Faction Talk used to be standard for XM Radios on 103, but Sirius subs needed to pay a premium and it was on 206. Many of these issues have been resolved, however.
I recall from several years a leaked plan to greatly reduce the number of terrestrial XM transmitters. I’m curious if they ever did that. We live up in Seattle and I’ve always understood we are quite reliant on them given the buildings, trees, hills, and relatively low angle of the satellites.
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I believe that they did reduce the number of terrestrial transmitters...greatly. I used to be able to see two signals on my XM radio: satellite and terrestrial. Now I only see satellite. While driving in the southeast Michigan area, the radio will drop out under just about every overpass. It didn't do this ten years ago. I'm sure it's all about the money and there's no revenue stream from having repeaters.
