Step 5: Build the amplifier output Molex Connectors

Given the pinout diagram posted in step 2, it is easiest to begin building the Molex portions of the harness from that side. These two connectors will receive amplified output from the Alpine.

I first built the Molex connector that will receive outputs of amplified front signals. In matching my speaker wires to the wire colors in the X9331, I followed standard household electrical convention. Black and red are positive, white and green are negative. I used red (+) and white (-) for left side signals, and black (+) and green (-) for right side signals. The order of wires on the Molex connector is not crucial as long as the colors are the same when the outputs from the amplifier are mated with the harness connectors. When I finished my front side Molex appeared as follows.



I followed the same protocol in building the harness for the amplifier rear speaker returns. Note that in this image, the my female X9331 is inverted. Keep that in mind in comparing the speaker wires to the labeled diagram in Step 2.

 

Ditto on the Sticky status for this thread!!

another awesome update. Well done! thank you!

 

Step 6: Build the Amplifier Input Molex Connectors

In this step you will be working on the male side of the harness which mates with the female side of the Mini X9331 connector. So these two Molex connectors are designed to send front and rear speaker output to the Alpine.

This step is fairly simple. First, push the x9331 pins into the back end of the male connector with colors in exactly the same positions as they are on the female connector. You will have two each of black, red, green, and white wires. Then group wires into two bundles of four so the wires in the bundles are coming from exactly the same positions on the male side as on the female side. One bundle will contain the front side speaker wires and the other the rear side speaker wires. Then push the Molex pins into the Molex connectors in the same order you used on the female side. You will end up with two Molex connectors, each containing a black, red, white, and green wire.

In my case I made one small exception. I used a six pin Molex connector for the speaker leads that will feed head unit front speaker outputs to my Alpine rather than the four pin Molex connectors I used everywhere else. Why? Because my Alpine needs an on/off signal to turn on and off as the Power goes on and off in the car. I've been told there is an on/off lead in the X15 connector that piggybacks on the X9331. If I can locate that feed, I'll feed to the Alpine through the fifth pin of the six pin Molex connector.

When you are finished the front speaker input and output side of your harness should look like this. Note that there is one four pin and one six pin Molex on that side. I put a piece of black tape on each of those Molex connectors to mark the connectors I plan to use in connecting with my Alpine.



The following image shows the rear speaker Molex input/output side of the harness. I don't plan to use either of these connectors in my install. But if I change my mind later, they are there.



I won't be able to install and test the speaker operations through this harness until I position, run power to, and run speaker lines to and from the Alpine. So I'll set it aside for now.

 

Derepente,

Why thank you. It is comments like yours that keeps me going.

 

A number of posts back in this thread I decided to do a rear seat delete on my MCSC. Doing so allows me to use the rear seat foot wells for the Alpine (drivers side) and SO powered sub (passenger side). In that position, full seat travel is possible on the drivers side and nearly full on the passenger side.

I'm going to design the rear seat delete with the objective of being able to reinstall the rear seat if necessary to occasionally haul people. I do have small grandkids. With that in mind, I plan to put quick disconnects to power and speaker leads on both units and use industrial Velcro to attach them to the floor.

Given how quickly the X9331 can be accessed once you know what you are doing, it would take only a few seconds to disconnect amplifier leads and use a small Molex ended 4 line wire to bridge the front inputs and outputs on the harness allowing the door speakers to be powered directly by head unit output, which is exactly what I have right now. Or I could just yank out the harness and reconnect the factory male and female X9331, although yanking a harness in and out with that many wires (20) makes me nervous.

Having just pulled the lower drivers kick plate panel to access the x9331, I realize that it will be relatively easy to run speaker lines down the drivers side to the drivers side rear footwell. With the battery on the passenger side, the obvious path for the (+) power line is under the passenger kick panel, then across to the components under or just behind the seats. That achieves the objective of keeping the power runs as far away from the speaker runs as possible minimizing the potential of hum being induced into the speaker runs by the power lines.

I do have a fairly significant amount of two and four wire #16 speaker cable designed for home installation. You saw a piece of the two wire in my door install and wires from the four wire in the harness I just built. Ideally, I'd take a four wire and a two wire run from the six pin Molex connector in the harness back to the Alpine and return the amplified signals with another 4 wire back to the harness.

What I'm struggling with is that these cables have plastic wrappers and are non-shielded and non-twisted pair. I'm giving some thought to cutting aluminum foil into strips and using spray-on adhesive to wrap the 3 cable 10 wire run with aluminum foil. As an alternative, I could run shielded or twisted pair but I don't relish the the thought of keeping it all straight with all the 10 lines being either one or two colors. It is a lot easier to sort out with four color wires being grouped into two-four and one-two line run.

I know quite a bit about electricity but am no electrical engineer. I'd like to hear your thoughts on this approach. Given that the weatherman is predicting chill factors in the -20 degree range over the next few days, I have some time to think about it.

Thank you for your thoughts.

 

This has got to be the best install write up I have ever seen! The idea to make a pass through connector for that x9331 connector is brilliant. Most installers would have just piggy backed off the wire itself.

For me Im VERY glad the dealer was able to find a MCS with the HK system. I certainly could do this but glad I did get the HK system.

 

Phaetton

The problem with the piggy back solution is that signals from the head unit are still being passed through to the speakers unamplified. Not sure whether or not this causes a problem if two signals are being passed through to a speaker, one amplified and the other not. For example, depending on the length of the run to and from the amplifier, there is the portential for the two feeds to be slightly out of synch. That's a situation I wanted to avoid.

I also think building a harness between the male and female X9331 connector is a brilliant idea. I wish it was mine. All I did is take ideas spread around this site and pulled them together. But thank you for the nice compliment on my writeup. It is the first harness step-by-step I've seen with a complete set of reference photos.

This sequence applies to anyone with a 2nd generation MINI that wants to add an amplifier to their system, not just to 2011 Cabrio owners.

Oh, by the way - I already have my own duuuhhh response to my on the aluminum foil. It is called aluminum tape and available at nearly every home products store in the country.

Tom

 

Yep that connector idea is the best method but working in the car biz for 9 years, worked at a Dodge dealer before it all went to hell, I learned a lot about how those small audio shops do crappy jobs installing gear and hide it behind panels that the owner will never pull off.

That being said we did have one guy do a killer install of a full blown Infinity setup in a PT Cruiser for a customer. He had the car for about a week. When we had to replace a window regulator we were amazed at the attention to detail and over all clean install.

 

This thread is awesome to say the least.

 

I have learned so much from the people at this site in two short months. The feedback is very gratifying. I do teach adults for a living and I've been doing computer tutorials since the Apple II sprouted floppy drives in the late 1970s and Visicalc came along.

What's happened so far is I ripped off a variety of ideas from other folks, applied them to this project and used my photography and adult ed skills to build this thread. I hope it encourages some readers to take on an audio upgrade that might not otherwise do so. As far as I'm concerned, it is a fair payback for everything I have learned.

Again, thank you for the feedback. I look forward to meeting some of you in person.

 

What exactly are you trying to achieve by shielding your speaker wires? It doesn't sound like a good idea.

 

Speaker wires are commonly shielded to prevent hum induced by lines running power.

 

A shielded wire only protects you from electrostatic interference and does nothing for electromagnetic interference (what you are describing), while changing the characteristics of the transmission line (speaker wire) by introducing more inductance to the load of your amplifier for the sake of protecting yourself from interference that you probably don't even have.

Most humming/alternator whines/etc. that people hear come from bad ground connections at the amp, not the speaker wires.

 

Wuttuptae,

I indicated I'm not an electrical engineer ... but

Both amplifier installation kits I have received in the last few years contain either twisted pair or shielded speaker cable. My incoming line from my dish satellite is shielded as are most of my RCA speaker lines from my audio systems.

Help me understand why shielding is used in all these settings and why it doesn't apply here. I'm not challenging your statements, but after all, my name is Thomas.

 

I'll try to explain what I know (it's been a long time since my EE/CmpE days) and try to distract you with big words where I'm fudging it. Faraday cages block electrostatic interference, in or out. Stuff dealing with RF, dimmer switches, lightning, computers.. they all generate electrostatic. Your PC's power supply (or any switched-mode) emits quite a bit of electrostatic.

You might say, hey there's a lot of that floating around in a car... but not really. Your audio signal, even before you touch it at the X9331 connector, got bundled with a lot of other signals, mazed its way through a ton of electronics, and still, you don't hear any interference. At your speaker wires the signal is relatively strong so any noise it picks up would have to be really strong for you to hear it, which leads us to EMI.

Electromagnetic is everywhere (it's one of the fundamental forces), but in audio (as it pertains to interference) we're particularly interested in large emag fields -- and that requires large amounts of electricity. The right-hand rule shows you which direction an emag field points, so if you have a signal going north, you'd point your right thumb in that direction, and then your fingers curling would show you the direction of the field, which is occurring around the wire.

So if you run your speaker wire parallel to this wire, you will pick up its electromagnetic field... which is interference in our case. If you cross the wire at 90 degrees, you pick up very little EMI. It's easy to see this if you have two right hands, and if you do, I'm your #1 fan. Shielding does nothing to stop this from happening.

BUT, why CAT5 cable, for example, is twisted in pairs is because the sending and returning signals would (in theory) cancel out each other's emag field. The twisting kind of randomizes the direction of the emag forces to help cancellation (since you're not sending and receiving the same exact signal at the same exact spot on the wire).

Why TRUE balanced cables work is because the noise picked up in one conductor would also be picked up in the other conductor -- leaving the voltage difference between the two the same as the original signal. The receiver on each end would difference the two signals, removing any unwanted noise. Nothing to do with the wire.

I don't think shielded RCA cables would do anything because the shield needs to be grounded for it to be a Faraday cage. They come twisted, too, which probably does help a little, but there are no return signals, so you won't get the same benefits as something like CAT5. So my guess is it helps just a wee bit.

And last, shielding essentially creates a coupling of the two conductors that was not intended. Through inductance, one affects the other.

 

wuttuptae

Wow. Actually you didn't leave me totally in the dust. I had a year of high school and two semesters of university physics. But it has been 45 years and at my age there is only so much room on the memory shelf.

Thank you for taking my request seriously. I run a company with 3 IT types and 3 development types. When they recommend that I do something or not do something they have come to understand the first word out of my mouth will be 'why?'

They used to try to blow me away with terminology. They have come to realize that just results in a series of more 'whats?' and 'whys?' These days they dumb it down to a level I can understand.

I mentioned earlier I was struggling with whether or not to shield as I suspected much of what you just said was the case. But it would drive me crazy to put all the work into this project and come out the other side with a noise problem.

So now that you've kindly taken the time to explain 'why', I'll accept your recommendation. Thanks.

Tom

 

My two cents: if you do end up with noise at the end, it's best to identify what's causing the noise (rather than trying to block it). BTW, I'm doing my own install on pace with yours, so hurry up so I can learn more before I get there!

 

wuttuptae

Been really cold here in Wisconsin. But I'm hoping to run cables this weekend. Of course, the Packers-Falcons game knocks a piece out of the weekend schedule.

Tom

 

Tom - A couple of suggestions if I may? The foam will keep the crossover from sitting in any accumulated water but it's still unprotected against any water that runs into the door and might drip on the crossover. I'm not a huge fan of door mounting crossovers because the constant door slamming can loosen the components on the board, but your location will minimize that. If you have the time, I'd suggest wrapping the crossover with plastic (Ziploc bags work well) and then sealing the bag to the wires with duct tape. This will greatley extend the life of the crossover and keep corrosion to a minimum. Also, if you can, create a drip loop, a section where your speaker wires droop below the crossover, to keep any water that runs down the wires from getting near the crossover.

If you feel adventurous and want to explore an active setup (which will require speaker and amp changes) Dayton Audio drivers, available at Parts Express, are dirt cheap and sound amazing.

 

Quality Sound

Thank

 

Quality Sound

Thank you for the suggestions. They all sound like good ideas. Next time I have the door panels off, I'll incorporate your suggestions.

Tom

 

tom
thanks VERYmuch for the details on door panel removal. i'm giving it a whirl tomorrow and was nervious about that mirror control removal! going from hi-fi to some (probably) very average speakers from kenwood with hopefully some marginal improvement. i'd just like the speakers to not cry when they are unable to reproduce sound they are asked to by the stereo...

 

Tom - I just read the posts about shielding your speaker and signal cables and the advice you got is absolutely correct. Unfortunately, the marketing wizards are better at spreading half-truths getting people to overspend on cables than we are at getting real facts out.

Also, and this is moot because of the way the car is already set up, running power and signal/speaker cables on opposite sides of the car does NOTHING to prevent or eliminate noise. Here's why. Voltage flows pos to neg but current flows neg to pos. The car's chassis is your negative cable. There is no way to move the signal cables a significant distance from the chassis. Ground loops are another myth perpetuated in car audio. Simply grounding two pieces of gear in different locations is, by definition, a ground loop.

I can totally appreciate the attention to detail but you are a bit over-concerned about some things that, as long as your install is solid, and judging by the install so far, you're in good shape, you simply don't need to worry about.

 

Great thread. I'm planning on doing a sound system upgrade on my 2011 convertible very soon. I'm curious, has anyone tried to install a pair of 6.5" subs in the rear speaker locations on this car? Kicker makes these

http://www.crutchfield.com/S-FMQejbp...-08CVT654.html

and if they fit where the rear speakers are, it would save a lot of space and not require putting a sub under the seats or in the boot. I could simply use a 4 channel amp and run the front channel to the front speakers and the back channel to the subs in the back. I have a 400Watt rockford fosgate amp and would be using that.

 

I just read through the whole thread...wow...what a great write up...good job!!

Now, is there a chance for finishing up? I'm curious as to how you mounted the amp / sub and the results.