[el_duderino]

Hi, all. I own a car AV shop in Portland, Oregon, and we're doing a 300C for a local company. They'll be using this as their show vehicle, and we're doing an OEM upgrade as follows:

1) Dom's company has modified the Nav HU.

2) We are modding the OEM VES system to have a video output to the modded HU.

3) We are using the OEM HU outputs to aftermarket amps (A DLS A8 4-channel and A6 mono amp).

4) We'll use the center speaker for the nav voice and bluetooth as has been described here previously.

5) We will remove all the other OEM speakers and install DLS Ultimate Series 6.5" midwoofers in the F doors and R deck, and their 1" silk-dome tweeters in the dash and R deck. Their tweeters play so low that we will still have a LOT of midrange in the windshield (I think the xover point is 2500 Hz).

6) We are installing a DLS Ultimate Series 12" subwoofer in the trunk in a fiberglass sealed enclosure. The spare will be pretty useless since large wheels are being fitted, so we will use the spare well for the sub and position the amp rack just forward of that. We want the installation to be as stealth as possible, but when you do see eomthing, we want it to be show quality (not IASCA competitor quality, perhaps,but show quality none the less).

7) We'll also install a Clifford two-way remote-control security system with remote start, and a Clifford GPS system (as soon as they come in!)

So over the next week I plan on posting photos as we work and blogging the status of the job. Any questions anyone has, I'll be happy to answer as soon as I can, but I might not get to them until after the project's over, just so you know.

One question I'm working on answering this weekend is how to retain stereo muting with the OEM Bluetooth system and still use the HU preamp outputs and not the amplifier speaker-level outputs.

Oh, and thanks to all who've posted valuable information on the forum about the audio system.

 

[chasb]

When it's done you have to

Show Us A Lot Of Pictures

 

[Reno]

Can you please spell out the acronyms and detail their functions for us A/V (Audio Visual) challenged Chrysler 300 owners?

 

[el_duderino]

OEM means "factory".

VES is Chrysler's term for the rear-seat Video Entertainment System. It's all over the AV forum : )

HU means Head Unit - the in-dash CD player.

And Hz means Hertz, which is a measure of frequency and refers to a particular note or vibration.

 

[el_duderino]

OK, first big thing to note on this car:

It seems different than some 2005's discussed on this board. I'm assuming that a production date of 6/23/2005 is a 2006 model. I don't mean to contradict anyone else's findings with another car, but this was a big enough surprise to me that we tested and re-tested, so I'm confident that this car was not what I expected after reading other forum member's comments.

This car has a fixed 2-channel line audio output between the factory CD player and the factory amplifier. Not only was it fixed in level, it was huge in level. With a 1K sine wave test disc, I measured 2.45 volts RMS and 7 volts peak-to-peak with a Flike Scopemeter. The factory deck in an Acura sends maybe 1.5 volts peak to peak and good aftermarket decks usually send 4 to 5 volts tops. I had to change the input sensitivity of my NTI audio analyzer to measure frequency response on this preamp line, and it was flat as a pancake.

But the amplitude was not the big deal. The big deal was that it did not change with the volume setting. At all. Not a darn bit. We tested it with the Fluke Scopemeter and the shape of the sine wave didn't budge (nor did the numeric display)! To make sure the setup was good, I tagged a speaker output from the amp and IT changed hugely with volume, no problem. This seems to be a new development.

So we will be using speaker level converters and summing their output together and then running the signal into an EQ to correct all this factory equalization folderal.

With this car I never had the chance to solve the Uconnect/Nav audio problem (which is pretty weird). When you disconnect the CD player's audio output from the factory amp, you lose Uconnect and Nav audio too... but the wires from the factory CD player/nav unit show NO audio coming out the factory CD player at those times. No signal at all. And research shows that the audio from the nav brain and the Uconnect box go into the CD player and nowhere else, so when things are working normally, the audio signal MUST be on those lines between the Factory CD player and the factory amp. There's no other way for them to get there (assuming thay haven't started digitizing this signal and putting it on the CAN bus : ). So the CAN bus must be foiling attempts to retain those features and replace the factory amplifier, by killing the audio from them when the factory amp isn't working correctly (or something like that).

We will take the F 6x9 output (which is NOT high-passed at all - these door speakers get all the bass there is) and the front dash speaker output (which is high-passed at about 120, and possibly low-pass filtered at about 18K too, hard to say) and we will step them down and then sum them together. We will EQ the 18k rolloff and eq the dips in the midrange response. (The EQ we use here is a 4-band parametric.)

If you'd like to see the response curves of the signal sent to the factory speakers by the factory amp, see this:

http://kward1.homestead.com/300audio.html

I did not post the preamp out signal, because I ran out of memory, and because it's flat as a darn pancake anyway. Great signal to tap a Clean Sweep into - and with this car, you WOULD lose your volume control from the HU and the steering wheel.

Remember that pink noise, the test signal used here, is a randomized noise that is equal in energy at every octave, so it corresponds to how humans hear. It should measure perfectly flat on these speaker wires, and any deviations from perfectly flat are either crossover filters or equalization in the factory amp.

We are not implementing fade in this car - it does have R speakers, but we're not using a fader. The nav and Uconnect voice will come out of the L side speakers. If we were we would do it by adding a knob, since I don't want to mess with the rear-speaker equalization. If we wanted to ONLY have the nav and Uconnect voice to come out the L FRONT speaker, we would need two equalizers. Not in the budget, I'm afraid. We could run the rear speakers unequalized if we have to, but at present, we'll see how this works out.

I tried not to use any three-letter acronyms : )

 

[nick_danger]

I'm no authority on this, but according to the CANHACK folks, the nav and UConnect voices are sent over the CANBUS and the only way around it is to devise a stock amp "emulator". Just a device that can take the clean source signals and output them as 6-channel low levels to maintain all the stock HU features.

Great writeup, I'm really looking forward to seeing (and hearing) the outcome of your progress.

 

[Lik2race]

I'm no authority on this, but according to the CANHACK folks, the nav and UConnect voices are sent over the CANBUS and the only way around it is to devise a stock amp "emulator". Just a device that can take the clean source signals and output them as 6-channel low levels to maintain all the stock HU features.[/FONT]

.

WHAT ?? I'm really lost now..haven't a clue as to what you just said. But..I am glad you know,'cause we NEED people like you, to help people like us ( "Older Retired Guys" ). OK..You can get back to your conversation,or whatever that was..

 

[el_duderino]

Nick, thanks for the kind words, but I've been to canhack.org and read about the "amp emulator" and I haven't found any post that says what you said... can you possibly post the link to the right thread for me?

I'm no authority on this, but according to the CANHACK folks, the nav and UConnect voices are sent over the CANBUS and the only way around it is to devise a stock amp "emulator". Just a device that can take the clean source signals and output them as 6-channel low levels to maintain all the stock HU features.

Great writeup, I'm really looking forward to seeing (and hearing) the outcome of your progress.

 

[nick_danger]

It's not there? WTF? Hold on...

 

[nick_danger]

Sorry about that, the post about the amp emulator was not made on the canhack.org forums, it was the lxforums.com. I also misquoted him slightly, I apologize for any confusion.

http://www.lxforums.com/board/showthread.php?t=15412&page=1&pp=30

Linuxkid has lots of other great info there as well regarding his efforts.

 

[el_duderino]

OK, read that thread, useful info, but yeah, I don't see the Uconnect and the Nav on the CAN bus. Don't think that's how it's working...

 

[nick_danger]

OK, read that thread, useful info, but yeah, I don't see the Uconnect and the Nav on the CAN bus. Don't think that's how it's working...

Hmm, you're right, he doesn't say that... exactly. I just arrived at that conclusion since he's working on a amp emulator that will allow us to keep all stock functions, but he has to hack the CANBUS to do it. Obviously if there is no amplification being sent for those signals from the HU, it must be an underlying digital signal that is constant and always active and therefore wouldn't be detectable unless you were looking for bits and bytes instead of hertz. Why do I suddenly feel like Morpheus from the Matrix? Odd.

 

[el_duderino]

He's hacking the canbus to get the volume state codes and the fader position codes. Bacially, if you drew a block diagram of a car stereo, the preamp is in the cd player, but if you draw a block diagram of a home audio rack system, the preamp is separate from the CD player.

In the 300C, the preamp is in the amp and controlled digitally by controls which just happen to be on the front of the cd player...

 

[nick_danger]

He's hacking the canbus to get the volume state codes and the fader position codes. Bacially, if you drew a block diagram of a car stereo, the preamp is in the cd player, but if you draw a block diagram of a home audio rack system, the preamp is separate from the CD player.

In the 300C, the preamp is in the amp and controlled digitally by controls which just happen to be on the front of the cd player...

:nutkick:

Hmm. I should just e-mail him directly and ask him to spell it all out for me in detail, because now I have no idea what's going on. My world is falling to pieces.

 

[el_duderino]

OK, plot thickens, but begins to make more sense.

When the factory amp is CONNECTED to the factory CD player, the output is fixed in level, and the Uconnect and Nav audio are passed through the CD Player on the 2-channel preamp output.

When the factory amp is DISCONNECTED from the factory CD player, the audio output is variable with volume! HOWEVER, at that point the factory CD player stops passing the Nav voice and the Uconnect.

My best guess is that there is an application where the CD player is connected to a different amp and that configuration does not have a CAN-bus controlled external amp and does not support Uconnect and Nav voice.

That explains why my results were different than those who had totally disconnected the amp. We had tried tapping the audio lines today with the factory amp in place, to retain Uconnect functionality, and that's when we discovered that the lines were fixed in level.

 

[el_duderino]

Oh, and that output will go 22V peak to peak before the waveform starts to clip... sheesh.

 

[jaydee]

22volts p to p?

22volts p to p? Does that mean they have an inverter in there somewhere?
Jay

 

[el_duderino]

It's an analog audio output, and audio is a/c by definition. But they have a lot of voltage...

 

[vvv90]

I wouldn't hold out much hope for the tape deck though.



Or the Creedence.

 

[el_duderino]

OK, fun bit number two today: Finding unbacked carpet to match the light taupe-ish part of the two-tone interior was problematic. Apparently you need to let the swatches fade for a decade or so and then the swatches match, but the new material won't.

So we decided to re-do the trunk in a matching gray and have just the floor mat done in the lighter color. FOr a daily driver it will probably get les marked up, but we were looking at lightening up the trunk interior...