Mike in MD

Heard mention here that the '03 cars have MOST Bus radio's. Will this help or hinder integrating XM? I couldn't find anything about it in Archives.

Trying to avoid the FM Mod. install method.

Anyone have XM in an '03 car? Howd ja do it?

TIA

Mike

ltc

Mike,
Yes, all MY03 Porsches (986 Boxter, 996 Carrera, E1 (Cayenne) and the Carrera GT) have a MOST bus connecting the headunit to the amplifier to the cd changer, etc. The 997 also has the same optical bus structure.
MOST is designed for OEM's and to date I have seen no one offer an aftermarket MOST audio component. The hardware is not the issue, rather the software. Without substantial OEM support (Porsche or Becker) it would be very difficult to integrate an additonal component to the ring and have the headunit recognize and control it without new software being downloaded into the headunit. If you do a search, I believe I have posted links to MOST information in response to similar posts.
This is an issue with Porsche, Audi (new 2004 A8, incredible sounding car BTW) and Mercedes (S class and Maybach super luxury car).
The MOST OEM's are assuming that once integrated into the vehicle, no one is going to want to change it. To do so would be a large amount of work, since MOST is a ring topology, you can not just unplug a component from the ring and leave it open. Further, there is no guarantee what the network/headunit will do once it recognizes that something has gone off the network. Furthermore, there is no longer any analog cables/wire between the headunit and amplifier, so replacing all the components would also mean adding substantial wiring harnesses thru the firewall (like the MY02 and previous line level based analog bus designs)
Your best bet at this time would be to integrate the XM's line level outputs into the Becker headunit via AUX or CDChanger inputs (if you don't already have a CD changer; or the FM modulator.
Let me know if you have any futher questions, feel free to email me.

P.S. In case you were wondering why anyone would have such useless information, I designed the MOST DSP amplifier for Bose Corp that goes in all the MY03/04/05 Porsches, new 2004 Audi A8 and 2003 Mercedes S and Maybach, so I am a bit of an electronics geek as well as a Pcar owner!
The best part of the job is going to Germany and tooling around on the Autobahn after midnight in some very nice cars and working with cars that are MY06 and beyond.

Mike in MD

Thanks for the detailed answer (from one geek to another)and email offer Itc. I hope to take you up on it down the road.

For the board though: Does the current head unit have both an AUX and a CD input. The car I hope to take delivery on tomorrow(!!!) has no changer. You give me hope that I can add both an aftermarket changer and an XM receiver without any FM Mod.

Some serious geek work. Sounds challenging and fun.

ltc

Mike,
I will check at work tomorrow to see exactly what's on the back of the Becker 9x6 MOST headunit (I know it is a totally different one from the Cayenne's).
In the meantime, have you tried posting/searching on the Becker board?:
<a href="http://www.beckerautosound.com/wwwboard/wwwboard.html" target="_blank">http://www.beckerautosound.com/wwwboard/wwwboard.html</a>
Happy New Year,

MKW

Lewis, I've noticed what most of us '02 owners with the BOSE system have complained about - excessive bass boom at idle but balanced at highway speed when bass set at " O " and loudness turned off . Was the system optimized on one of these midnight autobahn runs ?
My two Benzs have BOSE also, but they seem nicely bass balanced whether idling or at speed. Is there an explanation for this ?
BTW, I noticed you have finished designing the amp for the '03-'05 .Uhhh,,, gee, I wonder if that means the true next gen 911 " 998" is what you allude to as '06 and beyond ? <img src="graemlins/xyxwave.gif" border="0" alt="[bigbye]" />

ltc

MKW,
First off, the customer has the final say on equalizations. Actually, it is the Porsche senior executives (and in one case a wife if a board member) on their week long test drives before the car is approved for production who approve the final EQ settings (along with everything else about the cars).
Yup, the Germans really like bass, so it was eq'd for sonic performance at Autobahn speed (no, not one my midnight runs!) with all the engine and road noise.
There are lots of things that could have been done, i.e. use the in cabin microphone (used for vehicle noise cancellation, to dynamically adjust bass/eq with ambient noise or simply use the availabale speedo information to adjust bass with speed, but the customer (Porsche) liked it just the way it is.
(BTW, I design the electronics, not the transducers nor the equalizations/tunings).
As for the Cayenne, given the cabin volume, front engine and road noise, the bass is a bit more balanced with speed...it sounds very nice (and the Cayenne Turbo drives just like the reports have said...simply amazing)!
I am heading back to Germany the end of Jan and hope to get to drive/listen to the 997 and (if I'm lucky this trip) the Carrera GT.

As to what you referred to me alluding to... yes.

Happy New Year,

Zigzagn

ITC, Very interesting thread. Would you be able to tell me how to connect or wire my i pod into the Bose system? I do not have the remote CD changer.

Thanks in advance.

INVICTO

Lewis,

I am also interested in adding XM or Sirius (not FM Mod.), as well as a PhatBox MP3 player (or similar Kenwood Music Keg), into my '02 TT - stock PCM head unit w/ changer but not DSP.

I've got the wiring schematics from the Factory repair manuals, but, like you said, the S/W is the key. Any ideas?

TIA,

Steve
So. Cal.

ltc

For MY01 and MY02, the interface between the headunit and amplifier is differential line level analog signals, so the interface is pretty standard and well understood by aftermarket car audio installers.
MY03+ is digital optical networked bus (MOST). MOST is going to drive aftermarket installers (and owners) nuts.

Companies like blitzsafe have made a nice living out of selling adapters for just this purpose; i.e. interfacing line level analog aux sources to the cars.
Here is an example of one of their products that allows you to connect an analog source (mp3 player, ipod, sat radio, etc) to an Audi/Becker headunit w/o the cd changer:
<a href="http://www.blitzsafe.com/blitz_catalog/blitz_interfaces/blitz_installnotes/inst_audiaux_v1/inst_audiaux_v1.html" target="_blank">http://www.blitzsafe.com/blitz_catalog/blitz_interfaces/blitz_installnotes/inst_audiaux_v1/inst_audiaux_v1.html</a>
Here is a link showing a step by step installation in an Audi S4:
<a href="http://forums.audiworld.com/s4/msgs/1000892.phtml" target="_blank">http://forums.audiworld.com/s4/msgs/1000892.phtml</a>

This little device is merely a set of RCA jacks for the analog interface along with a little circuit to fool the headunit into believing that there is a CD changer still there. Push CDChanger on your headunit and listen to your aux source all day long.

These types of products are available to most car audio installers and they know how to interface this type of equipment.

Now if you already have a CD changer, then you can cheat by installing a switch to allow to you select between CDChanger and your extenal AUX analog source. In this mode, you just play the disc(s) in the CD changer to keep the headunit logic happy and connect the switch to your aux source to play thru the headunit/speakers (just ignore the headunit display of disc, track, time, etc). Not perfect, but cheap and it works. When you want to play your CD changer as always, throw the switch back to its normal position.

FWIW, I would not bother having a CD changer in a car along with an iPod/MP3 device; I prefer the functionality/portability of an iPod to a changer.

For MY01 and MY02 cars, your easiest route is via an aftermarket installer who can install route your ipod or XM to your available aux thru a simple switching controller/panel. You are going to be limited to the one available AUX input provided by the Becker headunit, so if you have more than one, you will need an external switch of some sort. For MY01 MY02 cars, they're analog systems, so luckily you don't have to worry about headunit software or network software!

(If my day job doesn't pan out, I guess I could design Pcar audio systems adapters!)

Happy New Year,

MKW

Thanks Lewis - you da man ! Glad I have an '02.
Did I read you correctly that there is active out of phase in- cabin noise cancellation on our '01-'03 Turbos like on those expensive BOSE headphones for planes ?
If so, does it only work , then , when the sound system is on ? I've never seen any reference to this .
( Someone should develop noise cancellation circuitry that lets owner tune the perceived in cabin exhaust sound to a choice of anything from a 427 Shelby to F1 Racer to Rolls . Now THAT would be a gold mine of a start up audio software business.)

Zigzagn

Thanks Lewis for all the great info!!!!

i Pod in the TT, can it get any better??

INVICTO

Thanks Lewis,

You spoke of a Becker head unit AUX input, does the PCM (Nav) have an AUX input as well?

Steve

ltc

MKW,
Having a pre MY03 certainly makes audio interfacing and upgrades a bit easier.
Yes, MY03 was the offical debut of Bose AudioPilot (vehicle noise cancellation or VNC)in all Porsches. The small microphone on the dash samples cabin noise (with headunit on) and adjusts equalization dynamically, primarily for low frequencies, like the noise cancelling headsets. The wonders of digital signal processing!
Zigzagn,
Yeah, an iPod in the car is very nice indeed. After I put one in my S4 (winter car), I'll probably end up with one in my TT. Now that they have wired remote in the iPod via headphone jacks (play, stop, tracks and volume), I've started thinking of an interface design to allow the headunit to think it's changing CD tracks when in fact it is changing tracks on the iPod. Not perfect, but it would be nice to not have to handle the iPod when driving and do it thru the headunit. Maybe a late winter project down in my home lab!
INVICTO,
I am pretty certain that the 01 and 02 PCM headunits are the same (Becker) unit, so there is no external aux input accessible. You would have to go in on the CD changer input. Some of the smaller (single DIN height) Becker units have an aux input and you can purchase a $20 dollar aux input cable for those. Don't recall ever seeing one for the PCM headunit.

Mike in MD

UPDATE and Head Unit removal question

Posted the 2003 Aux port question to the Becker board.

<a href="http://members4.boardhost.com/beckerboard/" target="_blank">http://members4.boardhost.com/beckerboard/</a>

Got a response from Becker service and a name and number to call. (nice response Becker!) Thanks Ronn

Tech said the '03 radio schematic makes no mention of an available AUX port, but he didn't have a head unit around to actually look at one. He suspected that it has been deleted, but wasn't sure

Anyone had their '03 head unit out? Itc? If not, can I do it with standard tools or do I need a Becker tool? Archive links anyone?

Must resist FM modulation

TIA