SL/R231: SL550 back speakers PROBLEM SOLVED!
Member
Joined: Aug 2010
Posts: 130
Likes: 24
From: Connecticut, USA
2017 SL450
Timing is everything in life.
I just this minute got home from Best Buy, where they installed that Alpine Amplifier. Although they thought it'd be perhaps an hour and a half job, it actually took them just under 3 and a half hours. I sat in their TV lounge and read a book, while relaxing in a very nice recliner.
Now to the actual job: They did fantastic work. Once back together, you couldn't tell that the car was ever apart. The amp works wonderfully, and the sound now coming out of the car is really great. I just couldn't be happier. They offered me a number of locations where they would put the amp, and I elected to have it put in the little smugglers box, behind the drivers seat. They could have hidden it, but then it would have been a royal pain in the butt to do any further adjustments to the sound volume/quality. This way, all I have to do is open the compartment and adjust to my hearts content.
The Best Buy guys were great. I'd give them a 10 out of 10. They also told me that their work is guaranteed forever, and to stop back whenever I wanted them to take a look at the system.
I'd recommend them in a NY minute.
JJ
I just this minute got home from Best Buy, where they installed that Alpine Amplifier. Although they thought it'd be perhaps an hour and a half job, it actually took them just under 3 and a half hours. I sat in their TV lounge and read a book, while relaxing in a very nice recliner.
Now to the actual job: They did fantastic work. Once back together, you couldn't tell that the car was ever apart. The amp works wonderfully, and the sound now coming out of the car is really great. I just couldn't be happier. They offered me a number of locations where they would put the amp, and I elected to have it put in the little smugglers box, behind the drivers seat. They could have hidden it, but then it would have been a royal pain in the butt to do any further adjustments to the sound volume/quality. This way, all I have to do is open the compartment and adjust to my hearts content.
The Best Buy guys were great. I'd give them a 10 out of 10. They also told me that their work is guaranteed forever, and to stop back whenever I wanted them to take a look at the system.
I'd recommend them in a NY minute.
JJ
Member
Joined: Aug 2010
Posts: 130
Likes: 24
From: Connecticut, USA
2017 SL450
They took off virtually the whole inside of the car, behind the drivers and passenger seats, from the floor (not the mats) up to and including the panel that hangs vertically, which holds the middle rear speaker. Apparently they have a resource online that gives them step by step directions in the removal of all that stuff.
Member
Joined: Mar 2016
Posts: 75
Likes: 15
'13 SL550
They took off virtually the whole inside of the car, behind the drivers and passenger seats, from the floor (not the mats) up to and including the panel that hangs vertically, which holds the middle rear speaker. Apparently they have a resource online that gives them step by step directions in the removal of all that stuff.
I was at my local Bestbuy first, and the technician took 3 hours to determine he wasn't confident enough to finish the job even though he consulted with Jeff (or his partner) who worked on jetjok's car. Apparently there is a master installer in each area, who is more knowledgeable of installations like this. The master installer happens to be in Pasadena for LA area, and his name is Eddy.
Then I scheduled an appointment with him, and Eddy finished the job in 2 hours.
Now the speakers do perform like a sound system in 100k+ car should. I am not an audiophile, but the difference is significant. I can't be happier with the result, and I highly recommend anyone who owns a 231 to fix this issue. You won't regret it. The standard charge is $119.99+5 material fee. The amplifier costs $149.99 in Bestbuy.
MBWorld Fanatic!
Joined: Oct 2010
Posts: 8,125
Likes: 4,353
From: Corona Del Mar, CA
2019 SL450, 2019 E450 Luxury Trim Wagon, 2024 BMW I7 xDrive60
Thanks to jetjok, I got mine done today at Bestbuy Pasadena, CA.
I was at my local Bestbuy first, and the technician took 3 hours to determine he wasn't confident enough to finish the job even though he consulted with Jeff (or his partner) who worked on jetjok's car. Apparently there is a master installer in each area, who is more knowledgeable of installations like this. The master installer happens to be in Pasadena for LA area, and his name is Eddy.
Then I scheduled an appointment with him, and Eddy finished the job in 2 hours.
Now the speakers do perform like a sound system in 100k+ car should. I am not an audiophile, but the difference is significant. I can't be happier with the result, and I highly recommend anyone who owns a 231 to fix this issue. You won't regret it. The standard charge is $119.99+5 material fee. The amplifier costs $149.99 in Bestbuy.
I was at my local Bestbuy first, and the technician took 3 hours to determine he wasn't confident enough to finish the job even though he consulted with Jeff (or his partner) who worked on jetjok's car. Apparently there is a master installer in each area, who is more knowledgeable of installations like this. The master installer happens to be in Pasadena for LA area, and his name is Eddy.
Then I scheduled an appointment with him, and Eddy finished the job in 2 hours.
Now the speakers do perform like a sound system in 100k+ car should. I am not an audiophile, but the difference is significant. I can't be happier with the result, and I highly recommend anyone who owns a 231 to fix this issue. You won't regret it. The standard charge is $119.99+5 material fee. The amplifier costs $149.99 in Bestbuy.
Last edited by Streamliner; Jul 23, 2017 at 11:10 AM.
Member
Joined: Mar 2016
Posts: 75
Likes: 15
'13 SL550
The OP spent $600.00 to get his B&O system upgraded. Then someone else contacts that same shop and is quoted $1,425.00 & two days for the same job, but you got yours done in 2 hours for like $275.00? Do you have the B&O or the HK? Where did they put your new amp? How much of the interior did they need to disassemble? Thanks.
I have HK, and yes, mine was done in 2 hours. My amp is hidden under the smuggler box, but you can ask the installer to put wherever you like. The installer only need to disassemble in the back, nothing in front. However, I didn't watch the entire process as you too are probably much better off sitting in Starbucks next door than waiting in the heat. The car audio section in Pasadena store was separated from the main store, thus no AC.
Member
Joined: Aug 2010
Posts: 130
Likes: 24
From: Connecticut, USA
2017 SL450
I too used an Alpine KTP-445U. The installer gave me a number of options, most of which would have been hidden behind some panels. However, since this is a leased car, and I'm not sure if I'll be purchasing it at the end of the lease, I decided to have the amp put in the box, directly behind the drivers seat. They had to drill one hole, about 3/4", to get the amp cannon plug in, on the outboard vertical side of the box, and the box is then in a location, from which additional adjustments can easily be made.
MBWorld Fanatic!
Joined: Oct 2010
Posts: 8,125
Likes: 4,353
From: Corona Del Mar, CA
2019 SL450, 2019 E450 Luxury Trim Wagon, 2024 BMW I7 xDrive60
Mine was done with Alpine KTP-445U amp. It was different from what the OP did. (It does cost that much to do it with OP's way.) @spyder987 was the first to introduced this solution, and then @lifeinitaly found the right place to perform the job.
I have HK, and yes, mine was done in 2 hours. My amp is hidden under the smuggler box, but you can ask the installer to put wherever you like. The installer only need to disassemble in the back, nothing in front. However, I didn't watch the entire process as you too are probably much better off sitting in Starbucks next door than waiting in the heat. The car audio section in Pasadena store was separated from the main store, thus no AC.
I have HK, and yes, mine was done in 2 hours. My amp is hidden under the smuggler box, but you can ask the installer to put wherever you like. The installer only need to disassemble in the back, nothing in front. However, I didn't watch the entire process as you too are probably much better off sitting in Starbucks next door than waiting in the heat. The car audio section in Pasadena store was separated from the main store, thus no AC.
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Member
Joined: Aug 2010
Posts: 130
Likes: 24
From: Connecticut, USA
2017 SL450
Streamliner, the guys at BestBuy, along with myself, determined what sounded best and the rear speakers, now powered in part by the Alpine amp, was set to perform that way. The volume and everything else that was normally controlled by the volume knob and radio settings are what controls the rear speakers now. All functions worked exactly how they did before the install, including the mute button on the steering wheel. You can manually change the rear speaker settings by using the two control knobs on the amp, but once set, I didn't find a need to do so. Hope this answers your question.
Member
Joined: Mar 2016
Posts: 75
Likes: 15
'13 SL550
So, do your regular volume controls, on the dash or steering wheel still control the overall volume, including that of the rear speaker? Does the mute still work? I am assuming you use the volume control on the new amp, as sort of a fader and that once you get that where you want it, the sound system still operates as it did before the mods, just with much better sound. Is that correct? Thanks.
Yes!
Does the mute still work?
Yes!
I am assuming you use the volume control on the new amp, as sort of a fader and that once you get that where you want it,
No, see jetjok's explanation.
the sound system still operates as it did before the mods, just with much better sound. Is that correct?
Hell yeah!
Last edited by greatkoei; Aug 13, 2017 at 06:18 AM.
Senior Member
Joined: Feb 2009
Posts: 280
Likes: 8
From: Sarasota FL
2020 E450 Wagon
Amp Volume Settings?
Just found and purchased a 2013 SL550 in the color combination I wanted (Silver W/Red & Black). I had read about the sound system lacked rear sound stage. Without any discussion to my wife about it, the first thing she mentioned as being disappointing was the sound system. So I have already purchased the Alpine amp. Hoping to shorten set-up time, can any of you who have already have had the Alpine amp installed please share where you have the volume set for the side and center speakers? By the way our car has the standard system rather than the optional B&O.
Thanks
Thanks
Member
Joined: Aug 2010
Posts: 130
Likes: 24
From: Connecticut, USA
2017 SL450
If you plan on installing the amp yourself, I'd suggest not doing that. If you plan on having it done professionally, such as at Best Buy, I'd not worry about shortening the installation procedure, for a few reasons: 1) Best Buy charges a fixed rate for the install, regardless of how much time they spend installing it; 2) only you and/or your wife would be the best judge as to where the amps' settings should be, because everyone is different in their hearing, and so what I think is perfect, you may not. Best of luck, and congratulations on your new car.
Senior Member
Joined: Feb 2009
Posts: 280
Likes: 8
From: Sarasota FL
2020 E450 Wagon
Thanks for the Best Buy suggestion. I may go that route if my amp languishes in the box too long. I have "control issues", meaning concerns about how sympathetic the local Best Buy installer will be to the car. Just like dealer techs, not all are created equally.
I already have the wiring diagrams. Shouldn't be too hard other than access. Just run the rear outer & center speaker outputs from the car amp through three channels of the 4 channel amp using speaker level inputs. What could possibly go wrong?
I'll report back if I get to this before season starts at work. Hopefully we'll be too busy enjoying the car to tinker with it.
I already have the wiring diagrams. Shouldn't be too hard other than access. Just run the rear outer & center speaker outputs from the car amp through three channels of the 4 channel amp using speaker level inputs. What could possibly go wrong?
I'll report back if I get to this before season starts at work. Hopefully we'll be too busy enjoying the car to tinker with it.
Member
Joined: Aug 2010
Posts: 130
Likes: 24
From: Connecticut, USA
2017 SL450
Just be advised that the installer mush have taken off 15 or 20 different panels to get to the wiring and placement of the amp. I hope you have the correct panel removal tools. It's like doing a jigsaw puzzle, in removing and replacing those panels. I think my guy got all those directions from the web, but am not sure. Good Luck.
Member
Joined: Mar 2016
Posts: 75
Likes: 15
'13 SL550
Thanks for the Best Buy suggestion. I may go that route if my amp languishes in the box too long. I have "control issues", meaning concerns about how sympathetic the local Best Buy installer will be to the car. Just like dealer techs, not all are created equally.
I already have the wiring diagrams. Shouldn't be too hard other than access. Just run the rear outer & center speaker outputs from the car amp through three channels of the 4 channel amp using speaker level inputs. What could possibly go wrong?
I'll report back if I get to this before season starts at work. Hopefully we'll be too busy enjoying the car to tinker with it.
I already have the wiring diagrams. Shouldn't be too hard other than access. Just run the rear outer & center speaker outputs from the car amp through three channels of the 4 channel amp using speaker level inputs. What could possibly go wrong?
I'll report back if I get to this before season starts at work. Hopefully we'll be too busy enjoying the car to tinker with it.
Senior Member
Joined: Feb 2009
Posts: 280
Likes: 8
From: Sarasota FL
2020 E450 Wagon
What could possibly go wrong was obviously meant to be tongue in cheek. The truth is: Whatever can go wrong, WILL go wrong 
My situation is a bit different, my day job is running a full service independent Mercedes-BMW repair shop. That doesn't mean we seek customer sound system upgrades, but I think we can certainly R&I some interior panels. What I have realized after rereading the posts is no one has indicated which outputs from the factory amp are being used as inputs to the Alpine amp. At first I thought that the rear channels were being boosted by the Alpine amp. But if there just isn't ANY signals to the rear channels during radio or Ipod source play, that doesn't appear likely to work.
Does anyone who has had the Alpine installed happen to know how it was wired? What channels from the factory amp were used as inputs to the Alpine?
My situation is a bit different, my day job is running a full service independent Mercedes-BMW repair shop. That doesn't mean we seek customer sound system upgrades, but I think we can certainly R&I some interior panels. What I have realized after rereading the posts is no one has indicated which outputs from the factory amp are being used as inputs to the Alpine amp. At first I thought that the rear channels were being boosted by the Alpine amp. But if there just isn't ANY signals to the rear channels during radio or Ipod source play, that doesn't appear likely to work.
Does anyone who has had the Alpine installed happen to know how it was wired? What channels from the factory amp were used as inputs to the Alpine?
Newbie
Joined: Jul 2017
Posts: 10
Likes: 1
From: Houston, TX
SL63 AMG 2017, E400 2015, SL550 2007
Like everyone else here, about the only thing I don't love about my vehicle is the front/rear sound balance, and I find this thread very interesting... If I've followed the thread correctly, it sounds like as long as I'm OK with burying the front/rear fade control that we're adding with the amp (set and forget), the entire Alpine based mod can be accomplished by accessing speaker wiring under the trunk "floor" and splicing the amp in there. Some have mentioned removal of interior panels, but I think that was either for the original more complex solution or for owners that wanted the new Alpine amp somewhere more convenient. Is that correct? Also curious if that holds for both HK and B&O versions (I've got the B&O in mine but this seems to be a common issue). I've already done a tour of the trunk internals to install a SmartTop mod, so I'm fairly excited about the relative ease of accessibility if the amp and wires are all in that area....
I was also wondering if anyone happens to know what power the factory amps can send to the rear speakers. I'm assuming a 4x45 Alpine amp isn't really pushing the power range any, we're basically just using it as a level-shifter here, correct?
Thanks to all for working on this and sharing....
I was also wondering if anyone happens to know what power the factory amps can send to the rear speakers. I'm assuming a 4x45 Alpine amp isn't really pushing the power range any, we're basically just using it as a level-shifter here, correct?
Thanks to all for working on this and sharing....
Member
Joined: Mar 2016
Posts: 75
Likes: 15
'13 SL550
Like everyone else here, about the only thing I don't love about my vehicle is the front/rear sound balance, and I find this thread very interesting... If I've followed the thread correctly, it sounds like as long as I'm OK with burying the front/rear fade control that we're adding with the amp (set and forget), the entire Alpine based mod can be accomplished by accessing speaker wiring under the trunk "floor" and splicing the amp in there. Some have mentioned removal of interior panels, but I think that was either for the original more complex solution or for owners that wanted the new Alpine amp somewhere more convenient. Is that correct? Also curious if that holds for both HK and B&O versions (I've got the B&O in mine but this seems to be a common issue). I've already done a tour of the trunk internals to install a SmartTop mod, so I'm fairly excited about the relative ease of accessibility if the amp and wires are all in that area....
I was also wondering if anyone happens to know what power the factory amps can send to the rear speakers. I'm assuming a 4x45 Alpine amp isn't really pushing the power range any, we're basically just using it as a level-shifter here, correct?
Thanks to all for working on this and sharing....
I was also wondering if anyone happens to know what power the factory amps can send to the rear speakers. I'm assuming a 4x45 Alpine amp isn't really pushing the power range any, we're basically just using it as a level-shifter here, correct?
Thanks to all for working on this and sharing....
Newbie
Joined: May 2017
Posts: 4
Likes: 3
2013 Mercedes 550 SL
The 4x45 Alpine amp gives plenty of sound, it amplifies the sound from the Mercedes amp, It is not an audiofile solution but to me it sounds very good, actually it sounds better now than any other car stereo I have or had! You will not need anything bigger than the Alpine anyway. Since my Alpine was installed where the speaker are ( and it is invisible ) I also added a JBL Basspro SL as a sub that I hide under the driver seat. it was a nice improvement but not as drastic as the Alpine which is a must. The sub cost was $150 + $110 installation if I remember correctly. I took to Best Buy to the same guy who installed the Alpine and he did again a great job. I tried to upload a picture but the forum here would not let me and it would freeze.
Newbie
Joined: Jul 2017
Posts: 10
Likes: 1
From: Houston, TX
SL63 AMG 2017, E400 2015, SL550 2007
My thought on the power level was that we probably aren't risking anything on the speaker end with the 4x45, because it seems likely the stock system should have been capable of putting at least that much power to the back speakers. It just isn't balanced the way we want it.... Anyone come across the actual specs on the speakers?
I guess I'm also assuming the installations done here used individual channels vs bridging.
I may well have the folks at Best Buy do the work but my initial contact at the nearest store didn't inspire a lot of confidence. I'd like to know as much as I can about what needs to be done before turning them loose on it...
I guess I'm also assuming the installations done here used individual channels vs bridging.
I may well have the folks at Best Buy do the work but my initial contact at the nearest store didn't inspire a lot of confidence. I'd like to know as much as I can about what needs to be done before turning them loose on it...
Member
Joined: Mar 2016
Posts: 75
Likes: 15
'13 SL550
My thought on the power level was that we probably aren't risking anything on the speaker end with the 4x45, because it seems likely the stock system should have been capable of putting at least that much power to the back speakers. It just isn't balanced the way we want it.... Anyone come across the actual specs on the speakers?
I guess I'm also assuming the installations done here used individual channels vs bridging.
I may well have the folks at Best Buy do the work but my initial contact at the nearest store didn't inspire a lot of confidence. I'd like to know as much as I can about what needs to be done before turning them loose on it...
I guess I'm also assuming the installations done here used individual channels vs bridging.
I may well have the folks at Best Buy do the work but my initial contact at the nearest store didn't inspire a lot of confidence. I'd like to know as much as I can about what needs to be done before turning them loose on it...
Junior Member
Joined: Jul 2017
Posts: 50
Likes: 6
From: Kingston/Woodstock NY
SL 550 Mille Miglia 2016, Nissan GTR Aniversary #44/50, Mustang GT500 2014(800hp)
I have competed the Alpine install at BB. What a great job for 279 and change. The sound is very good. However, I think I will take it to the next level and put two under seat JBL Basspro SL's behind the seats between the seat rails. Anyone his done 
this? Any clearance issues? Pics please.
The installer at BB already has it wired for this option.
this? Any clearance issues? Pics please. The installer at BB already has it wired for this option.
Newbie
Joined: May 2017
Posts: 4
Likes: 3
2013 Mercedes 550 SL
I have competed the Alpine install at BB. What a great job for 279 and change. The sound is very good. However, I think I will take it to the next level and put two under seat JBL Basspro SL's behind the seats between the seat rails. Anyone his done this? Any clearance issues? Pics please. The installer at BB already has it wired for this option.
this? Any clearance issues? Pics please. The installer at BB already has it wired for this option.Here is a link to the SUB, it fits well under the seat
https://www.crutchfield.com/p_109BAS...c&awug=9007784
I bought an open box and it was only $150 but it looked new
Junior Member
Joined: Aug 2017
Posts: 24
Likes: 1
From: Tampa, FL
2017 SL550
I just bought the Alpine amp for my 2017 SL550 at BB in Tampa, FL and paid $145 for it and $80 for installation. What a great investment. Night and day. This was truly a great idea. Thank you all so much. My next trick is to purchase the Tune at Weistec. They say it'll give me 540 HP at the wheels.
We'll see. Thanks again all!!!!
We'll see. Thanks again all!!!!
Junior Member
Joined: Jul 2017
Posts: 50
Likes: 6
From: Kingston/Woodstock NY
SL 550 Mille Miglia 2016, Nissan GTR Aniversary #44/50, Mustang GT500 2014(800hp)
To Springer19, I just added the Weistec tune. 540 hp, but monster Torque at 615! Now the car embarrasses others that pull up. It is the torque that comes on at a low 1500 rpm. Just contact Moe at Weistec. You will not be sorry.
