Has anyone else noted a decline in audio quality with Mercedes satellite radio in recent years? I've owned two C300 sedans, 2008 and a 2012, both satellite radios sounded fine. Our 2015 C250 coupe with the upgrade audio system (Harmon Kardon), satellite radio audio quality sounds watery. Now have a 2019 GLC300 with the standard audio system, the same problem with satellite radio, just sounds watery. In contrast, I have never had this issue with Volvos, Acura and domestic automobiles. Is this a case of MB putting in the cheapest satellite radio they can? Just very frustrating.

 

I don't have a GLC (yet), but came to poke around here before leasing one. I do know that the overall SiriusXM sound quality has degraded over the years, as they add more channels and reduce the bitrate for each of the channels to squish them all in. I rarely do any "critical listening" using SiriusXM anymore, as their compression ratios have increased -- it's mostly CNBC and background music for me now.

 

HT is 100% correct.. the Sirius app gives better quality streaming thru my iPhone to my MB

 

Conclusion is 100% wrong!
Read what HT said:
”overall SiriusXM sound quality has degraded over the years....”
meaning iPhone and MB are both getting the same lower quality sound. Therefore there is no way for iPhone to get a better quality audio... or there is some magic in your iPhone to make up for lost bits?
Makes sense?

 

No, that does not "make sense"...

I'm not sure the path for their feeds, but that is not a foregone conclusion you can make without other information. If SiriusXM is simultaneously streaming their audio directly to the internet and to the satellites, the compression ratios and codecs can be far different.

Listening to Sirius via your iPhone is taking a stream they put directly to the internet; you can not assume it is the same compression as the one they have to fit into their allocated bandwidth to get up and down to a satellite. Thus it is entirely plausible that an internet stream of the same channel could be of better quality.

 

I haven't noticed a degradation in quality, but I have noticed the sound is considerably lower when using Apple Car Play and the blue tooth connectivity to my phone than using the native radio. When you disconnect & it goes back the sound blows your ears out!! Just one of those quirks I guess.

 

sorry, but have to say this post does not make sense at all
can you please put some real bitrate/compression numbers behind your speculation?

 

Then you should re-read it. I did not give any specifics. I merely pointed-out that your conclusion that the audio streams are identical is unfounded. The iPhone is not receiving a satellite audio signal, it is using an internet stream via UDP. It is an apples-to-oranges comparison; two different technologies. If that "does not make sense at all" there's not much I can do to explain it to you here. Sorry.

 

I read it, my friend.

And asked a simple and specific question: tell us what is the difference between Sirius internet and satellite bitrates?

If you don't know the answer, there is no need to repeat unfounded speculation.... Hope this helps.

 

Some searching says that satellite is variable depending upon the station and goes up to 48kbps/channel.

Internet stream has had 3 choices in their apps (low, high, maximum) and maximum = 320kbps.

That's what the never-lying internet says

 

True, internet is not trusted source.

And this is a good example. Asked Sirius customer support about the difference. And guess what is the answer? There is no difference. None.

Both streaming over the internet and satellite have the same max bitrate of 64kbps!

Moral of the story is get Spotify (160 free/320 premium) if you care about audio quality.....


‘

 

Look pal - I don't care who you "chat" with - and I could care even less about your self-invented "bit rate" challenge.

YES - Sirius satellite "fidelity" has suffered - and also interestingly - fidelity between different satellite channels is not equal as well.

YES - my SIRIUS app thru my cell phone sounds better on all channels (and channels have equal fidelity) - than my Satellite channels.

You can rage all you want - doesn't change my experience or my comparison between the two - and I have nothing to prove-to-you you or any other jerk

 

Interesting discussion, and no consensus at all. My own experience is that Blue Tooth does the best job of pushing audio through the Burmeisters, so much so that I often prefer to stream my favorite local HD radio station through the app rather than listen to it on the radio. Yep, the sound is crisper and cleaner than even HD radio, especially for voice. My MP3 collection also sounds better through the Blue Tooth than the media player, though the difference is small.

Here's my setup: I have a cheap (~$100) 7" Android tablet with Dolby Atmos dedicated solely to audio and which gets left in the car most of the time. (I went with the tablet because the larger screen makes it easier and safer to operate than a cell phone while driving.) The phone stays in my pocket with Media Audio disabled but I can still use Blue Tooth for phone calls.

For music I subscribe to Spotify Premium ($9.99/month) and download all my playlists in advance at the highest bitrate rather then stream them. Pulsar Player Pro is my choice for MP3's. After some experimentation I found it best to turn off the Spotify and Pulsar equalizers and just let the tablet's Dolby Atmos handle the equalizing.

And, oh yes, I dropped my SiriusXM subscription a while back, mostly because the data compression killed both the the high and low ranges and even with 200 channels they had nothing I really wanted to hear.

 

Sorry for not being able to reply back before now -- just read through the posts above, and would offer the following comments:

In my initial post, I was only addressing SiriusXM via satellite delivery to the car, but I do use the app quite often (both in the car and on my bus commute). When set to highest quality settings (SETTINGS > APPLICATION SETTINGS > AUDIO STREAMING QUALITY) -- set to MAXIMUM, the steaming quality is quite good. If it weren't for CNBC in the car, and the (now) free streaming, I would dump SiriusXM as the in-car quality isn't worth even their promotional pricing to me. Tidal is my music streaming service of choice.

In my Acura RDX (which the GLC is replacing), I almost always plugged a cable into the USB port to stream music,. That car has the ELS system, which is probably my favorite OEM system thus far. Quality wise, Discs/USB files (256kbs), music on my iPhone (also 256kbs) and Tidal via USB generally sounded the best, then SiriusXM via the app / other internet streaming services are very listenable, and then a very distant third place would be SiriusXM via satellite to the car, which pales in comparison. My experience is identical in other cars (wife's car with a pretty mediocre Beats system and our SL550 with the Harmon Kardon system) and a host of rental cars I've had with upgraded sound systems,

HD Radio is starting to suffer the same issue -- it's largely due to bandwidth as many stations have been adding more sub-channels (e.g., in the NY Metro area they are adding the AM channels as HD Radio sub-channels), which reduces the bandwidth available to the main channel. Now most HD Radio stations have a second and sometimes a third sub-channel.

The other issue is that most music's dynamic range is compressed more as most people are listening to music on ear buds and in cars -- so high dynamic range material (where the louder passages are louder and the softer passages are lower) is harder to hear in a noisy environment as the quiet passages get drowned out. I could write for hours on this topic, but this is an automobile forum and not an audio forum.... let's just say I'm not a fan of music that has been "overly squished"...

Speaking of autos, I found a 2020 GLC 300 in Brilliant Blue that has all of the options / packages I wanted, so I look forward to joining the GLC driver's club a week from today...

 

There is still a question:

how come same quality signal is better on one medium vs the other one?
placebo effect makes up for missing kbps?

 

its not the same quality that you receive through each medium. While SiriusXM’s source material is likely full CD quality on their servers, they transmit through the different medium using different compression algorithms and/or levels. Similarly, HD radio is also compressed, as is internet radio.

Wheb Sirius and XM first launched (as separate companies), both advertised 100 commercial free channels in near CD quality. Most speculated at the time they were using close to 128kbs back then as that was the “near CD quality” benchmark. Now they have twice the number of channels and the same spectrum las they originally did, so something has to give — and that was the bitrate. Despite the merger, they still simulcast the same signal over both legacy companies satellites as the hardware is incompatible.


For the commercial services it’s hard to tell the bitrate in most cases, but most internet radio is 64kbps according to my Denon audio receiver at home. I would guess that SiriusXM delivered via satellite is about the 48-64kbps mentioned above based on my perception of the sound quality.

Each of these mediums uses a CODEC (which is an (en)coder / decoder) and each time and at each step the audio quality is compromised in some way. So if you steam it to Bluetooth, it gets “retranslated” once again into one of the Bluetooth audio profiles,

All that said, some people hear a difference and some do not. As you may ponder, so people’s brains fill in the missing information and others don’t have as keen a sense of hearing (or simply don’t care about audio quality). To each, their own...

Here’s the easy way to see this for yourself. Use the SiriusXM app and set the streaming quality to maximum as I show above. Plug your phone into the USB port on the car. Park outside in a quiet place and the tune to your favorite SiriusXM music channel in the car and on the app. The app will be about 2 minutes behind the satellite broadcast so listen to a song via satellite and then go to the app. If the same song hasn’t started playing, press GO LIVE. While you’ll still be a couple of minutes behind, that song should start soon.

What you’re listening for is less dynamic compression, more detail and perhaps clearer high frequencies. What audiophiles would call the depth and air...

 

Mr Schnell won't believe you. He thinks he got his answer from a phone call with a customer service rep. He probably should have asked why they have "quality" settings in the app...they all use the same bitrate? That would be pretty strange (if not fraudulent).

One thing no one has clarified, but the majority of the time people complain about "compression" when it comes to audio it is not referring to an algorithm reducing the number of bits transmitted, it's an audio term that reduces the dynamic bandwidth of the sound. It's no good for quality listening in any situation, but works fine for casual listening in most cases.

It's not worth arguing. Everyone hears music differently. That's why people have been testing and debating stereo systems for 60 years.

 

Also Bluetooth goes via completely different EQ settings from the phone. Yes Bluetooth is also compressed and has reduced range but if you like the EQ settings more then it'll probably sound "better" to you.

I mostly listen to radio and FLAC off USB, and when I switch to the phone via Bluetooth there's a bunch more bass on the same tracks. I find it annoying because I have the car set how I want already.... but if you love bass?

 

I just picked up our 2020 GLC 300 2 days ago, and I thought it included Sirius Satellite radio servie but it doesn't. I didn't get the Package that has 3 months free Sirius along with the 64 colors, etc. and when I go into the Radio section Sirius is not listed as an option. Is there some way that can be activated by the dealer? I can't believe the "headunit" is not Sirius ready or that a separate tuner would need to be installed. I really don't want to get one of those upfit type tuners and install a separate antenna. Would greatly appreciate your help. Thanks.

 

I would suggest you affordably add the Sirius app to your phone...

 

I would 100% agree -- especially with Car Play and Android Auto built in, you really get the full OEM user experience. Just instead of selecting SiriusXM, you select CarPlay/Android Auto and then click the SiriusXM app icon on the vehicle's touchscreen. I use Tidal, and just listened to 2 hours of Tidal via the car's touchscreen on my way home from the dealer today. Other than plugging in the phone, everything else worked just as if the car had Tidal service built in.

My guess is that it can't be added -- do you have the MBUX Multimedia package? If not, you may not have a satellite antenna on your car, since it won't have GPS. Mercedes is notorious for not having upgrade capability -- I couldn't add Sirius to my pre-owned 2006 E500 since it didn't have the wiring harness for the antenna.

 

I have MBUX, so that’s why I think it may be prewired. The dealer is pulling the build sheet and will let me know Monday. I used CarPlay with my iPhone the other day and was listening to Pandora and it was very good. But I tried to make a call through the MBUX system and my phone wouldn’t connect over Bluetooth. I had been using it for a couple of days with no issues. I had the phone connected via cable. Any idea what was wrong. I disconnected it from the cable and it connected and I could make calls. The phone works fine except for this problem. I can’t imagine that you can’t make calls if you’re connected to CarPlay. Thoughts?

 

Make and answer calls via the CarPlay interface when you are using CarPlay.

 

That might work (I don't have an iPhone to try on my car) but with Android I found there was a separate setting that turned off Bluetooth while AndroidAuto was active. I disabled that and now Bluetooth works as expected and to make calls even while using AndroidAuto.