Does SiriusXM realize that if they upped the bitrate just a slight bit the channels would sound better?

[schmave]

On a similar note, why do the channels airing the upcoming sports schedules sound so awful? The quality couldn't be worse if they tried, and it's been that way for years.

 

[CTListener]

On a similar note, why do the channels airing the upcoming sports schedules sound so awful? The quality couldn't be worse if they tried, and it's been that way for years.

SXM uses the lowest bit rate possible on those channels, just enough for intelligibility, Reason: The schedules are on many channels at once, and bandwidth is at a premium. The assumption is that people aren't listening to schedules for more than a few minutes, until they find out about the game they're interested in, so why waste bandwidth on higher-quality audio?

 

[Don CT]

SXM uses the lowest bit rate possible on those channels, just enough for intelligibility, Reason: The schedules are on many channels at once, and bandwidth is at a premium. The assumption is that people aren't listening to schedules for more than a few minutes, until they find out about the game they're interested in, so why waste bandwidth on higher-quality audio?

But if the audio is so bad you can barely make out the barker why bother.

 

[schmave]

Agree with both. It is comically bad, like the speaker is coming through a tin can ... and that's on a good day.

 

[rparky54]

The quality of sound is superb streaming the channels and programs using the app, from the satellite, not so much.

 

[Barry]

In a quiet environment, the audio from the SiriusXM stream is better than from the satellites. But in a vehicle, the difference is not as apparent, with the ever present road and traffic noise.

 

[Don CT]

In a quiet environment, the audio from the SiriusXM stream is better than from the satellites. But in a vehicle, the difference is not as apparent, with the ever present road and traffic noise.

Ya some of the sports stuff on the app sounds better.

The barker sounds clean on the app.

 

[LDronglien]

SXM should have a sports app where you can go to find the channels quickly and easily. Then they can shut down these info channels.

 

[Don CT]

SXM should have a sports app where you can go to find the channels quickly and easily. Then they can shut down these info channels.

You only need one channel to feed the info. Not sure why they place holder it on all of them.

 

[ssndradio]

The biggest issue with audio quality, as previously mentioned, is that XM and Sirius used two different types of audio encoding. I believe XM used an AAC-based system similar to encoding used by HD Radio, while Sirius used a PAC-based system developed by Agere Systems. The issue is that none of these systems at the time where software upgradeable — I was more involved with Sirius at the time when it first launched, and the first chipset was actually very complex — IIRC it was 8 different custom chips, used plenty of power — and also had to deal with signal phase correction since Sirius opted for a figure-8 satellite pattern that meant the birds were always moving both relative to the earth as well as the radio (XM used a traditional geostationary orbit which meant that wasn’t as bad of an issue — but the look angle was much lower and XM had MANY more terrestrial repeaters than Sirius in the beginning).

Essentially this means that even years after the merger, there are still two completely separate encoding chains, using double the bandwidth and band layout. They have standardized on the XM-based system as well as moved all satellites into geostationary orbit for both broadcasts — but they’ve never been able to truly realize double the bandwidth… and what’s worse is that even within the respective systems you have multiple generations of the technology — as mentioned earlier the 300-400’s channels are a newer encoding generation from the XM side and the 3000s channels were previously used when Sirius tried their whole flop of “backseat TV”. Older radios cannot see these newer channels etc.

In a perfect world, SXM would be able to phase out all of these various technologies and release a radio that is software upgradable and can see both the A and B SDARS band — which apparently they have done in the last few years — and standardize to the latest version of the XM AAC encoding system — they’d be able to increase the audio quality back to near CD-quality audio as well as have room for another 50 channels — or another 150 channels if they don’t prioritize audio — but that is going to involve making every Sirius-chipset radio completely useless, and every single-band XM radio (everything made before the last 2-3 years that can only physically tune the XM side of the band) stuck with the channels they get now — since you have the issue of not only separate technologies, but the band being split in half — and the respective companies not thinking forward enough to make their radios be able to actually tune both sides — even if they couldn’t decode anything one one of them.

I’ve often wondered if they could easily reduce the Sirius side down to just one of their side bands and use the XM technology in the other half — making legacy Sirius radios receive a ~50 channel “best of” package and give people a reason to upgrade their radios on their schedule, while adding another 50-75 available channels for the modern SXM radios that can decode the XM system as well as see both frequency bands…

 

[K6JHU]

I don't know if it my imagination but I listen to Symphony Hall (Channel 78). It appears that they have changed something as far as CODEC or bit rate, because now I hear the channel in stereo (as apposed to their mostly mono). I can actually localize instruments on the channel (from the satellite).

 

[Mediafrog+]

Essentially this means that even years after the merger, there are still two completely separate encoding chains, using double the bandwidth and band layout. They have standardized on the XM-based system as well as moved all satellites into geostationary orbit for both broadcasts — but they’ve never been able to truly realize double the bandwidth… and what’s worse is that even within the respective systems you have multiple generations of the technology — as mentioned earlier the 300-400’s channels are a newer encoding generation from the XM side and the 3000s channels were previously used when Sirius tried their whole flop of “backseat TV”. Older radios cannot see these newer channels etc.

A few years ago I saw some reports that Sirius branded car receivers would lose support in 2027 as that vintage distribution would be dropped. Haven’t heard anything about this recently, any update? Our car that includes a Sirius receiver is a 2014 model, so would hate to lose the service, but then again we can always stream through a phone and Bluetooth.

 

[Echo4Thirty]

I have a couple of legacy receivers including a home component receiver. I haven't heard about legacy Sirius signals going away. I too am now curious about this.

 

[Theater of My Mind]

I had a legacy Sirius receiver in my vehicle that sounded absolutely terrible. I had to replace the head unit and upgraded to a modern SiriusXM Receiver in the process, and I was amazed at how much better it sounds. Same vehicle, same excellent speakers, providing a good comparison. I went from barely being able to listen to the horrible Sirius sound quality to finding the SiriusXM sound quality quite tolerable most of the time.

 

[pattywells]

I had an 2010 Ford Fusion with a Sirius radio. It sounded awful.
Then I had a 2016 Chevy with an XM radio. It sounded much better than the Sirius radio, but still not great.
Now I have a 2024 Mini with a SXM radio. It sounds similar to my XM radio. I certainly get more stations now, but at varying audio quality. Acceptable at best.

But ultimately, I am been indifferent about car audio - There is road noise 90% of the time, so the audio is (almost) always competing with the environment anyhow.

Home audio is a totally different ball game. The sky is the limit, and the source quality really matters. For me, almost all of the FMs in my area sound terrible on my home system due to their processing.

 

[Don CT]

I had an 2010 Ford Fusion with a Sirius radio. It sounded awful.
Then I had a 2016 Chevy with an XM radio. It sounded much better than the Sirius radio, but still not great.
Now I have a 2024 Mini with a SXM radio. It sounds similar to my XM radio. I certainly get more stations now, but at varying audio quality. Acceptable at best.

But ultimately, I am been indifferent about car audio - There is road noise 90% of the time, so the audio is (almost) always competing with the environment anyhow.

Home audio is a totally different ball game. The sky is the limit, and the source quality really matters. For me, almost all of the FMs in my area sound terrible on my home system due to their processing.

Don’t forget that engineers master for phones and ear buds. Not fancy speakers.

 

[Theater of My Mind]

Don’t forget that engineers master for phones and ear buds. Not fancy speakers.

Are you talking about the recording engineers and producers involved in the creation of the music, the mastering engineers who create the final media formats for distribution, or the broadcast engineers setting up the station or the feed?

If you mean the latter, then yes, that's correct. But studio engineers and producers aim for great sound, played back on the best equipment, at least on the original recording.

Mastering engineers who digitize that music for CD, digital files and streaming services typically run it through a mastering limiter that heavily clips the peaks off the waveform, minimizing the dynamic range and maximizing the volume. This is the "loudness wars" approach that has ruined the sound of digital music for decades, and it's designed to make the music "pop" on phones, earbuds, streams, etc., in much the same way as radio processing was designed to do.

However, a phonograph needle can't track a waveform that has been clipped and flattened out to such a great extent. It would distort pretty badly, so the vinyl mastering process has to retain more of the music's dynamic range so the stylus can track it well. That's one reason why vinyl is now the "hi-fi" format of choice for audiophiles. Despite having a much higher noise floor than digital formats, vinyl playback actually offers more dynamic range and musical sound quality than the digital version which has typically been crushed and clipped.

I often wonder how modern broadcast processing is designed to handle digital music to avoid further crushing these already heavily-clipped waveforms.