Seattle SCone

I've wanted to add a good line level input to my SC430's Mark Levinson system ever since getting my car, but nobody seemed to have a good solution. I haven't found a single aftermarket adapter for the SC430. Then, I found a little tidbit and contacted Rocky Livingston because he seemed to have been at least partially successful in this endeavor.

Using information and encouragement from Rocky, I opened the SC430 console and gained access to the audio signal harness. I also successfully injected a line level audio signal from my Archos MP3 player. Interestingly I discovered that one doesn't need to pull the head unit to access the audio signal lines. The audio signal and control cables go through a molex connector that is separate from the head unit and lies several inches below the head unit. It is near the right wall of the gear shift console. There are actually two connectors mounted together. The one of interest is the left one with quite a few wires coming out of it. Accessing the signal lines there means I don't need to pull the head unit. Only the wood panel/cup holder assembly need be removed.

Lacking a schematic, I coudn't totally verify my findings but, I believe I have narrowed down the left and right channel signals to the black/white (right) and red/green (left) wire pairs and a gray shield wire on the connector. Indeed, tapping the signal lines and injection of audio lets me pick up or inject audio into the Mark Levinson system. The signals appear to be balanced format with the red and green wires carrying the left channel, while the black and white wires carry the right channel. Direct injection definitely creates clearer audio than my cassette adapter, albeit softer.

As Rocky indicated to me, the volume, fader, and other functions of the ML amplifier are controlled by other control wires in the harness. Substitution of another audio signal by splicing into the audio signal lines leaves the controls active. I can actually adjust balance, volume etc. normally on the head unit while listening to my injected audio signal. Once I build a suitable switching mechanism to transfer the four signal wires between the normal head unit output vs the mp3 player output, I should be able to simply set my switch to select the MP3 player and use the head unit controls as usual. The head unit will simply play its selected source, but the ML processor/amp will instead receive the line level signal of my MP3 player.

My next task was to build a suitable means of selecting a new source input and converting the unbalanced output of my MP3 player to properly feed the balanced input of the ML system. I used a 4 pole double throw switch and a PIE DC blocker to do the trick. It worked! I cut the four audio lines and hooked up a 4 pole double throw switch to let me select between the head unit and signal from a PIE DC blocker. The four lines (Left+, Left-, Right+, Right-) lines to the amp were connected to the switch's center poles. The corresponding lines from the head end connect to their mates with the switch in one position. In the other position the four lines to the amp are connected to the shield and pin lines of the DC blocker.

No more need for a cassette adapter! Frequency response and dynamic range are much improved. No more tape adapter hiss or clackety clack of the adapter spinning either!


Guy Kuo

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Below info about opening the console and the signal lines is from Rocky Livingston.....


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....Correct, the head unit controls are still fully functional. The audio output from the head unit to the Levinson is 2 channel only. The Levinson unit processes and splits the signals for fader/balance etc… It’s a pretty easy process overall. To disassemble the console:

1. Start by lifting the center storage compartment lid and remove the seat heater controls. Press forward on the heater control piece from inside the storage compartment. It easily pops right out.

2. Then set the parking brake and move the gear shifter to neutral.

3. Starting at the seat heater control location, pop out the wood grain assembly on the center console. You will need to disconnect one or two light connectors connected to the assembly to fully remove it.

4. Pop out the wood grain assembly surrounding he head unit. This gets a little tricky because of some of power lid and ash tray wiring, but it’s still pretty easy to remove…

5. Now you should have easy access to the head unit and remove the 4 bolts holding it in place by using a 10mm socket wrench. You may also need to pop out the AC control assembly which is also simple to do. Just grab it with two hands and rock it back and forth until it pops out. It has 4 molex connectors you will need to disconnect.

I don’t remember which 4 head unit leads are audio. I downloaded a schematic off the net to figure out all this stuff… Unfortunately I’m not sure where I filed it.

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........... The below info about the signal lines is also from Rocky. He did his work by pulling the head unit. I'm doing it at the independent molex connector that doesn't require pulling the head unit. My point of attack means less disassembly than if one tries to do the work at the rear of the head unit. Rocky doesn't mention the signals being balanced format, but they certainly appear to be so from my examination..............


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This is a fairly straight forward design. The Pioneer/Toyota head unit, the unit with the with the CD player, has 2 or 3 molex connectors on the rear of the unit. The largest connector, I think it’s the middle one, has a 8 or 10 wires connected to it. 4 of these wires feed audio to the Levinson DSP/Amplifier system, 2 of the wires are a control bus which controls the Levinson sound settings, i.e., Bass, treble, balance, fader, volume…

So, you need to insert an external switch, such as the ones made by P.I.E, between the head unit and the Levinson Unit. I don’t have the cable plug pin-out schematic handy so I can’t tell you which leads to intercept. The external switch needs a ground loop isolator installed on it’s output to prevent hum and engine noise interference.

You will need to install a power switch somewhere to control the P.I.E. interface. When you energize the power input to the P.I.E., the unit will switch from one audio source to the other. I.e., an external XM radio, MP3 player, external aux audio connector etc….Audio controls from the head unit remain unaffected because the control bus from the head unit to the Levinson are unaffected…

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Seattle SCone

Here is the molex connector with cat 5e wire spliced in to carry the audio signals from head unit and audio input lines of ML amp to 4PDT switch. Be sure to resecure and loom the wiring.

The audio signals in the system are normally differential format (balanced) so each channel as a + and - signal carrier. The shield line is the signal ground. This posed problem because my MP3 player as unbalanced (RCA style ) audio output. A DC blocker allowed feeding of the unbalanced signal to the + and - phase signal wires of each channel.


I suspect the video lines of the navigator also pass through this area. Might be possible to intercept and add a video input for the navigator screen here as well. It would certainly be easier than pulling the Nav display out to access its connections.

Seattle SCone

4PDT Switch and DC blocker for new input.

steph280

What is that DC blocker? Is it a ground loop isolater?

I'm doing an unrelated project, retrofitting a Toyota navigation. The voice prompt can not be processed by the factory amp, thus I need to hook up an external amp with separate speaker. But the amp produces lots of static, making the voice all distorted. Tried different amps and samething. But if the amp is powered via a separate battery, noise is gone! So I suspect some type of groud loop or feedback. Maybe that DC blocker is what I've been looking for? I am not too familiar with the term balanced/unbalanced RCA signal.

Thanks for your help.

Stephen

Seattle SCone

It is also know as a ground loop isolator. The device allows AC audio signals to pass through, but DC isolates the inputs and outputs. It sounds like your problem would be solved by inserting one in your signal path. In my case I needed to DC isolate and allow connection of an unbalanced sound source into the balanced lines.

See http://home.btconnect.com/woodgreen/...chtip/art6.htm or http://homerecording.about.com/libra...y/aa082697.htm for an explanation of balanced vs unbalanced audio signals. The Martin Logan system uses balanced signals (like XLR in the articles) to improve noise rejection in the line between head unit and processor/amp.

steph280

What you said about balanced vs unbalanced signal makes perfect sense, now that we discovered a third shield pinout on the navigation headunit right next to the signal+ and signal- wire. Somebody suggested using either the signal+ OR signal - wire along with that shield wire as ground. I will give that a try.

Thanks again for your help.

Stephen

Seattle SCone

Are you doing a Nav to Video modification?

BTW, how do you take things apart to get access to behind the Nav display? I guess I could try attacking the video at the Nav unit in the trunk, but it would be nice to know how to take apart things in front without destroying everything. That's why I was so happy to find the audio cabling below everything so I could access the wires without taking things apart.

steph280

Sorry I should have mentioned this was in a Toyota Sienna, not SC430. There are technical service manuals for each one of the model that shows exactly how to take things apart. Unfortunately you'll need to buy them or be friend with a Toyota/Lexus tech. Taking the Sienna nav unit out is extremely simple, a 3 minutes job based on instruction posted on another forum. Other than that, the navigation system are all the same.

Stephen

Seattle SCone

Thanks for clearing that up.

Just finished getting my iPod hooked up in the car. I've arranged things such that only the mini remote control is visible at the left side of the center console. Its wire is routed into the console so only a short segment is exposed. Audio connection from iPod to my newly created RCA inputs was done via a Belden automobile power adapter which I modified to bypass its internal amplifier. I tried using it with the built-in amp, but sound wasn't as good. After modifiying the Belden unit, its output is now line-out from the iPod without any interfering amp. The Belden power unit was chosen because it sends a pause command to the iPod when the engine is turned off. The iPode then powers down in a few minutes. Upon engire restart, I need only tap the play button of the remote control to instantly restart playback where I left off.

By use of playlists and shuffling, I can keep well entertained using just the controls of the iPod remote. I don't even need to see the iPod which is tucked out of sight in the center console. This is a LOT more user friendly and better sounding than the Archos/cassette adapter solution I used for the last two years. Got total support for it once my wife saw how much easier it would be for her to run. She hated trying to pick tracks from my Archos Jukebox. I never expected that Apple's iPod interface could be this much better. It's total night and day!

Now off to drive some more to enjoy both my SC and my music. Ain't life grand?

Seattle SCone

Hidden away but easily accessed, the iPod is ready to feed the Mark Levinson sound system with over 16 continuous days of MP3 music.

Seattle SCone

iPod remote allows easy access and control without visual distraction during driving. By using playlists and shuffle mode, I can simply listen to the current track or skip forward to another one without taking my eyes off the road. The buttons are easily distinguished by touch so fumbling is not an issue.

This arrangement is much more convenient than burning new compliation discs or using my Archos. I simply make new playlists in iTunes. The iPod has its song files and playlists automatically synchronised with the computer as soon as it is plugged into its docking cable.

Flexiblity and ease of use were never like this.

Seattle SCone

I wasn't completely satisfied with the remote being visible so I relocated it into the coin holder. With the holder cover shut, nothing is visible at all.

mwbuck

Hey, i have to say...that is awesome. I'm trying to do the same thing in my RX300.

Seattle SCone

Thanks.

I've since extended the length of the remote cable by splicing in a 2 foot segment of wire onto the serial control wires of the remote (blue, green & yellow wires). This let me route both cables through the hole I put into the rear of the top compartment's bottom. Wire dress is much neater than having one come up through the front and the other through the back.

With this much more cable, I now have the option of pulling the iPod forward far enough to sit in a cup holder. Most of the time it just stays hidden in the console compartment.

Hohlraum

man, this is really good information. assuming i don't want to do this, any semi-compitent audio place should beable to use this as a reference to get the job done easily right?

Any one know if the GS430 ML has the molex in the same place?

Seattle SCone> where did you install the power switch for the PIE GLI? How hard was it to get the wood facing off?