Well I had Sirius installed in my GS last week and have the following observations.

1) I have reception trouble around my house due to the tree lined streets.
2) Thursday, we drove over 200 miles from New Jersey, 87 North to Albany then 90 West towards Syracuse. I lost the signal about four times during the 3.5 hour drive for about a second or two. This was not related to any overpass and it was a clear night
3) The sound doesn't sound full, it sounds like some DJs are talking into tin cans
4) Sunday, we drove another 200 miles from Hamilton, NY down to Route 17 back to New Jersey. I only lost the signal about two times. It worked great on the local roads in Central New York.
5) Today I drove to New York City and I had no problems.

I can take the lost signal here and there, but I would think that the sound quality should be better than FM, but it isn't. I have the ML and the quality just isn't there. Lastly, Sirius works fine with the NAV system as far as channel selection except the titles are cut off on the screen.

 

I just bought my GS300 with ML yesterday and it came installed with sirius from Longo Lexus of El Monte. I also am having issues with it cutting out for a second here and there. If this was the only problem I would be very happy. The quality of the sound is rubbish . About equal or sometimes worse tha FM. I was briefly driving the Acura RL with XM and a Honda Accord with XM and both cars never cut out in the locations that the sirius struggles in and the sound quality was beyond reproach. Especially in the RL which has maybe the second best system to the GS300.

I will gladly go to the dealer and have them uninstall Sirius and install XM (I'll pay) if I was sure that the XM would be as it was in my previous rides. But first I'd like to hear from someone with XM and the ML system and how they would rate the quality of the sound. Maybe there's something wrong with Lexus' side of the implementation? I really hope that it's a Sirius issue and not the Lexus' as sat radio is pretty awesome.

 

#1 can be typical for DAB radio in suburban areas without repeaters. Your radio either needs a line of sight path to the satellite or within range of a ground repeater.

#2. Some areas just have weird things going on. The DAB signals are running in the 2.x GHz range (exact number escapes me). If something bleeds into that area, then you will have interference. In the DC area, there is a place on I-95 in Woodbridge that XM drops out every time no matter which car/receiver I have.

#3. Not sure why this is. I have not experienced this with XM. I don't think I have heard others with Sirius have mentioned this either.

#4. When you lose the signal, check to see if there are tall trees in the area and/or large concentrations of powerlines. Tall trees are essentially giant water bags and block many 2.x GHz signals. Powerlines are notorious for spewing interference.

#5. NYC probably has a nice ground repeater network like DC has. I can be in the 3rd street tunnel in downtown DC and not lose XM (XM HQ is less than a couple miles NE of there).

I would try to find a friend with a similar setup and go for a ride with him or her and see if the same problems are occuring there. If not, it sounds like your box or antenna may have issues.

SP

 

I've never had Sirius but I've had XM in my GS since April of this year. I think it's great and plan to purchase a XM receiver for home use. The only time I experience dropouts is in heavily wooded areas or in the mountains (recently I've driven several times through WVA). I can't receive the signal when the car's in my garage, but that's expected. I never have dropouts in clear areas. I think the sound quality is very good to excellent, and is much better than FM. I don't like the limited character display, but I think that's the GS's issue, not XM.

 

"Sounds like some of the DJs are talkiing into tin cans"

I'm speculating here ... but I know that certain satellite television stations take advantage of different amounts of bandwidth. National Geographic would be among the higher; Nick at Nite (broadcasting many black-and-white programs) would be among the lower. Satellite radio could easily be the same way - primarily "talk" programming would be in the lower bandwidth usage (e.g., the music played occasionally on OutQ, channel 106 is not of as good audio quality as is the Spa jazz station).

Just a guess ...

Rob

 

Sirius and XM both use completely different compression technologies.

In a nutshell XM at all times has the same bandwith allowance for each station.

Example:

A pop stream, talk stream, and a country music stream would all be using the EXACT same amount of bandwith at all times.

Sirius uses a technology known as SPlex

Example

If there is a big drum solo, or another station playing a dance hit, the individual stream will pull bandwith from a less active talk stream, to improve that sound at that particular moment.

I have had Sirius and XM since their launch in a variety of vehicles(2001 Toyota Solara, 2003 Corolla Sport, 2004 Toyota Solara, and 2005 mini cooper) and both sound pretty similar, and both can sound "tinny" at times.

I would give XM the edge in overall sound quality, and sirius the edge in programming, original content, and sports.

One last note... XM has two dedicated satellites, one on the west coast, and one on the east coast, respectively known as "Rock and Roll" Sirius has 3 constantly revolving satellites in a figure 8 high above the US.

If anyone has any specific questions regarding either service, I would be happy to answer them.

 

Weezer, that is not totally true as each music channel has a constant bitrate but with each format getting a different number (music higher than traffic/talk). Both services offer the same overall bandwidth (12.5mHz). XM uses CT-aacPlus, a variation of the same aac format that Apple uses for their iTunes music store with a bit of extra tech to reduce the bitrate further. aacPlus supports variable bitrate encoding but I am not sure if XM takes advantage of that. Nor do I know if the decoders in the consumer equipment have that ability. I think they wanted to use CBR vs. VBR as to have a known quantity when it comes to what they are pushing down their pipe. Not saying this is good or bad but if you have quite a few spikes at the same time with no reserve space, that can be bad.

Also, XM has three satellites in orbit with a 4th to be launched in the next year. XM-1 and XM-2 ("Rock" and "Roll" respectively as you said) have solar panels that could degrade faster than expected. XM-1 has been replaced by XM-3 and XM-1 will operate as an in-orbit spare. XM-4 wlll replace XM-2 (and XM-2 will become the second spare). XM-5 is slated to be built in the next two years and could be launched in the '08-'09 timeframe.

SP

 

I read that some folks are using an XM antenna with Sirius. Is this because the SM antenna is more sano?

If I want to buy Sirius (Howard Stern addict) then where is the best place to buy? The dealer or a stereo shop?

 

I have been having lost signal problems with my Sirius almost every day. I wonder if it has anything to do with power lines? (We have a lot in this area)

In addition, I lost my signal when I parked my car along side of a wall!

It works great on wide open highways but it stinks in the city.