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How to tell if I have a fiber optic amplifire?

26K views 38 replies 11 participants last post by  rudeney 
#1 ·
I would like to replace my radio with one of the Chinese units sold on eBay and I am being asked if my car has a fiber optic amplifier. They told me if I have a fiber optic amplifier I will need to buy an extra extension kit in order for it to work.

QUESTION.
How do I know if I have a fiber optic amplifier???

I have a 2003 SL 500

Thanks for reading
 
#2 ·
I believe all USA model R230s came with either the Bose or Harmon-Kardon premium stereo systems as standard, and all use fiber optic to send audio and control data to the separate amp.
 
#3 ·
They told me if I have a fiber optic amplifier I will need to buy an extra extension kit in order for it to work.
I'll guess that extra kit will work for an '05 or newer vehicle but not yours. The fibre optics in '03 and '04 vehicles communicate via the D2B protocol, and every adapter kit I have seen is for the MOST protocol used in '05 and newer models.
 
#4 ·
all R230 have fiber channel, the 2003 however has D2B fiber, rather than the odd fiber found in 2004 models, and standard MOST fiber found in 2005 and later years.
 
#7 ·
So, I should be good to good...
Highly unlikely. Ask the seller whether the product interfaces with the D2B or the MOST optical bus -- it is one or the other and not both.

So MY2004 is not MOST?
Correct.

MY2004 is D2B. You can quickly verify this by checking your Web ETM optical bus schematic for a MY2004 car and by checking the EPC and comparing part numbers for the audio amplifier in '03-'05 models.
 
#8 · (Edited)
This is the unit I am looking at and this is the response I got from china.

http://www.ebay.com/itm/182425956318?_trksid=p2060353.m1438.l2649&ssPageName=STRK:MEBIDX:IT

Yes,this car radio can work in your car --D2B fiber in my 2003 Mercedes SL500.
For your car has D2B fiber,you just need buy a buy an extension kit(specific for MERCEDES BENZ) :http://www.ebay.ca/itm/252818633356
Then the car radio will work very well.
We will send you a very good quality car charger to you as a free gift if you buy it now.
We will ship them together by Express to you.
Usually 3-5 days will come to your door.
 
#10 ·
For your car has D2B fiber,you just need buy a buy an extension kit...
That kit is plainly a simple wiring harness consisting of nothing but wires, connectors, and a fuse. It can not possibly convert electrical signals to optical signals.
 
#11 ·
I see no fiber on that connector, so I suspect that it is actually a bypass cable that plugs into the back of the head unit and then into the analog wiring from the amp to the speakers. The amp is located under rear storage compartment that is behind the driver's seat. Looking at the photos, it appears to be at least 12 feet long, which should be enough to reach from the dash to the storage compartment.

If this is the case, it would not matter which fiber system you have (D2B or MOST) because this totally bypasses that and runs straight to the analog speaker wiring. This is just my guess!!
 
#12 ·
If this is the case, it would not matter which fiber system you have (D2B or MOST) because this totally bypasses that and runs straight to the analog speaker wiring.
But the head unit the OP is considering has no power amplifiers built-in and must be used with an external amplifier.
 
#13 ·
I don't see anything in the listing that says it requires an external amp, but I also don't see any mention of built-in amplification or wattage output. I suspect it has a built-in amp that maybe 25w/channel max, 12w/channel nominal, like most aftermarket radios. Their Chinese to English translation is not very good.
 
#14 ·
I suspect it has a built-in amp that maybe 25w/channel max..
The outputs are line-level "RCA" (see attached), and this implies no internal power amplifiers. Technically, you probably could omit an external amplifier and connect the outputs directly to the speaker system and hear something, but it would not be hi-fi, and as a practical matter no one would choose to do that.
 

Attachments

#15 ·
Yeah, I saw that, but again, the language translation is pretty bad. And looking at that extension cable, it appears that it uses the standard "Audio 10" wiring harness connections for speaker-level outputs. That's what makes me think it may have a built-in amp. But I could be wrong. Only the manufacturer-seller knows for sure, and they can't seem to communicate very well.
 
#17 ·
I am the OP and I went ahead a bought the unit with the cable.
You surely won't be able to use the factory amplifier and will have to improvise. There are a few things you should know.

The factory amplifier has 8 channels of amplification -- one for each speaker. Each channel is customized with equalization and frequency filtering to work with its speaker.

The factory speakers have no crossover network, since the necessary filtering is incorporated in the factory amplifier. Each speaker is electrically isolated from the rest, and there are a total of 16 speaker wires coming to the factory amplifier. Also, the factory speakers have an unusually low nominal impedance of perhaps 2 ohms or less, and depending upon the amplifier you have combining two speakers on a channel may not be a good option.

Whether the Chinese unit has an internal amplifier that you can use or you add an external one, I can't imagine how you are going to power more than 4 or 5 of the existing 8 speakers and not compromise sound quality in some manner.
 
#18 ·
Looking at the wiring diagram in WIS, the Bose amp seems to have 8 discrete speaker outputs:

H4/1h1 = Left Door Tweeter
H4/1h2 = Left Door Woofer
H4/2h1 = Right Door Tweeter
H4/2h2 = Right Woofer
H4/7 = Left rear speaker
H4/8 = Right rear speaker
H4/27 = Center cockpit speaker (centerfill)
H4/29 = Subwoofer

Here's the wiring diagram (one is a full page, the other is the same thing with higher resolution and includes the legend):

http://benzbits.com/R230/BoseAmpWiringDiagramFull.JPG
http://benzbits.com/R230/BoseAmpWiringDiagram.JPG

One thing of interest are the two rear speakers H4/7 and H4/8. These appear to be driven by a single pair of wires from pins 10 and 18 of the amp's output. I don't know how they can be discrete channels like that. Note that they are listed twice int he diagram, but at the top, it indicates a slight change in the wiring harness based on build date and region (Japan vs. Rest-of-World).

Anyhow, maybe this will help in your endeavor. I am very curious to see how this turns out. Also, I have heard that many people are unhappy with the Bose speakers when the Bose amp is removed. Apparently, that amp does a lot of custom processing of the sound to work with their speakers and the layout in the car. Once that is removed, they are just mediocre-quality 2ohm speakers. YMMV!
 
#19 · (Edited)
One thing of interest are the two rear speakers H4/7 and H4/8. These appear to be driven by a single pair of wires from pins 10 and 18 of the amp's output.
That is a detail I forgot about. The rear surround speakers are wired in parallel. So there are 7 speaker outputs (not 8).

The harness the OP ends up using will likely have 8 or 10 speaker wires, and he would have to figure how to wire that to the existing 14.

.
 
#27 ·
Hello...i not M city but i have installed this android comand in my car, at the end i have to replace the D2B cable and the Bose amplifier.

I send some photos...

The comand work ok, work with wheel buton, and the dound quality is good, i sure the bose system is a more quality sound but for me, the comand sound with the amplifier instaled is ok.


Enviado desde mi SM-G965F mediante Tapatalk
 
#29 ·
All apps is online, not use the usb or micro sd port of the comand.
I have a usb 4G stick in one usb port, the Comand have their own internet acces . With positioning system with google maps, i can check my car position when the comand is on :)


Enviado desde mi SM-G965F mediante Tapatalk
 
#32 ·
Yes, only need a extension cable for conect the comand main unit to where is located the Bose amplifier, not for use the bose amplifier, is because all connectors to all speakers are located in the output of bose amplifier.

This cable is 5 meter long and you can buy this at the same store where you buy the android comand.

The same seller have a interface for connect optical fiver to android comand but.....only M.O.S.T. , not D2B.

Enviado desde mi SM-G965F mediante Tapatalk
 
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