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1500 Auxillary Audio Solutions for MP3 Input     last revised May 22 , 2008

Reference pages are not intended to provide full procedural guides.  They are merely photos and comments, many submitted by others who have contributed them out of interest in helping others see what might help them in the same situations or if they just have interest in the subject matter.  I attempt to regulate what is placed here and may add my own comments but bear in mind these are in no way guaranteed to be tested by me.  Think of them as potential, future, Photo Guides under construction for your reference only.
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This content was posted here by:  Rudy
So, you just got your new Honda 1500 and you are wondering where the MP3 player or Satellite Radio unit plug in is.  Well if you have an interstate model, you are in luck.  Honda ripped out the tape player on that model and gave you a Line-in plug so you could use that input for those other things.  On the interstate, the plug (not jack, go figure) is under the left side fairing box.  You will have to take the box out to get to it the first time.

For the rest of us, we have to make a way to get the job done. 

There are 4 common ways to do this.  I list them below along with some of the pros and cons of each:

Typical Cost
Cassette Adapter
A special cassette with a wire sticking out of it to magnetically couple the audio output from a device through the head of the cassette player.
Cheap and readily available.
Not the best audio quality.  Head to head contact can cause wear or damage to the drive head.  Cassette transport has to run all the time (belts clutches, etc).  Wire and adapter must be inserted and stored.  Cassette door can damage adapter wire.  Lengthy wire must be kept under control.  Stereo seperation can be poor.  Tone equalization is usually way off.
$14.99 US
Wireless FM Modulator device
Either built in to a device as a transmitter or a seperate transmitting device.
Convenient if power source is available or built in to device.  Reasonable to use in remote areas.
Often not good audio quality.  Suffers competing interference from nearby stations on same or near frequencies.  Transmitter and radio must be tuned to same frequency.  Every time competing signals occur, both devices must be retuned to a new frequency.  Sometimes more than once in urban areas.
Wired FM Modulator device
A dedicated FM modulator that get wired to the bike and who's signal is injected directly into the antenna cable.
Most have good quality sound.  Does not suffer from surrounding interference.  Has good channel seperation.  Does  not need to be removed when ride is over.
More expensive than the above options.  Must be installed once.  Not quite as good audio quality as  radio modification but close.
Not available in every corner store.
Some of these devices are much worse quality sound than others.
Radio Modification
An internal electrical modification of the inside of the radio to tap into the system between the amp and preamp to add an extra line-in jack.
Best quality sound if ground loops and incompatabilities between the injecting device and the radio are resolved.  Can be done cheaply if the parts are obtainable.
Requires opening and modifiying the radio.   Some electronic and soldering skills are required.
Potential damage to the radio is possible.
Some method of getting a switch and external jack outside the radio is necessary and must be kept waterproof.  Radio must be removed from the bike to do the work.  Since there is no isolation between the radio circuits and the added device, the radio is more vulnerable to external electrical damage than any of the other methods.
$10 to $125

From here, I will speak from my own experiences.

Long ago I use the cassette adapters in my cars.  Some of them weren't too bad but they were very hot on the bass side and got boomy quick.  Many of the tape transports had problems with them.  They often had bad head alignments to the facing head tracks and azmuths in the player units.  Often heat warped them and many of the adapters had squeaky mechanisms.  But the main thing that got to me was that I never had one around when I needed it.

When I bought my GL1500 I decided to try using a Satellite Radio unit that had a built in wireless FM transmitter.  I live around a city area and found it really inconvenient to regularly have another station cut in to my program and interfere with it.  Changing the FM unit and the Radio channel on the fly while riding was difficult if not down right dangerous.  Then when I'd move to another channel and it would get interference on the other side of town.  Plus the audio quality was way below what I was willing to tolerate.  Plus just passing through cities on my rides brought me through areas of interference.  So the wireless transmitter was out. 

Then I decided to try a wired in modulator.  It had no interference problems and also better sound and channel seperation.  I have heard of some that aren't so good.  Somewhere on the web I was doing research on them and found the AudioVox FMM-100A from Circuit City and car stereo outlets.  I checked with a few of them and many of them also used the AudioVox in thier car installs.  I figured they had to live with the reslults so it must be ok,

I bought one and installed it and found it was more than acceptable.

I was going to do the radio mod also just to see the difference but I ran out of winter and things got good to ride so I never did it.  So far I haven't been sorry at all.
Many say that the radio mod has much less hiss noise and better audio.  The channel seperation would have to be about as good as it gets.  But it is also picky about picking up other bike, electrical  and ground plane noises.

I may try it later but I like the idea of the bike staying stock as much as possible and believe me, the AudioVox FMM-100A is good enough (for me at least).

Here is a quick tour of how I mounted and installed mine. 

Where to install and mount it...
Seems to be a trade off between sticking the modulator under the seat or under the left fairing box.  I have enough crap stuck up under the fairing pocket so I opted for the under the seat approach as shown below.


I  was worried about wetness and dirt getting in there so I covered all the box holes and corners with 3M Scotch tape (not the magic tape) to help seal it up a bit.
Then I cleaned the plastic fender under where I mounted the box and used 3M double stick foam tape to help hold it there.  Then as you may be able to see, I suspended it between
the two bike frame lateral bars with tie-wraps to keep it there. You can see the white tie-wraps in the picture attached to the mounting tabs of the modulator.
It is in contact with the bottom of the seat pan as you can see by the wear line across the label but just barely and it is no problem at all.
You might also notice that I adhered to my usual use of flex duct plastic channel to run the audio and power wires to prevent them from being worn against something and shorting out.

(above) Next I ran the ground wire (black) over to the battery.  I rarely if ever use the bike chassis for ground.  The white plug is to connect to the power switch that I mounted forward.

Here I shortened the fuse wire,..

I ran the fused +12 hot wire to a tap in the running lights circuit.  The reason I did this is because it was before I designed the Aux Power system and
 I wanted something with an even electircal load on it to reduce any system noise coming in on the power line.  The load of the lamps dampens electrical spikes.
Here I tapped in to the brown/green wire going to the rear running lights.

I had the option to insert the modulator's antenna wires at the radio itself or at the junction under the seat. 
I opted for the under the seat approach because there was no reason not to and I really didn't want to have to pull the radio and upper shelter cover.
You simply unplug the FM antenna at it's connection to the antenna extender cord and insert the FM modulator.

Next run the audio input feed to the front of the bike...
The unit comes with isolation transformers that plug into the audio line like an audio patch extender cable.  It has two black squares on it.
Those are the isolation transformers.  These prevent electrical ground loops to the modulator and they prevent overloads and transients from getting to the input stage of the modulator.
This also drops the signal a little bit so you will need a good hot headphone output from what ever MP3 player or other device you plug into it.
Below is a picture of where I tucked them in just under the edge of the left faux tank cover where the seat butts up to it.. 

You might use tie-wraps to keep the plugs from coming loose with the vibration from riding.
I had to learn that one myself the hard way once... thought I had blown an amp channel or speakers.

Next you add an audio cable to the front of the isolation transformer inputs so you can reach the front of the bike where your audio device will be and to mate correctly to it.
The jacks at the isolation transformer are the same type as shown above (RCA audio type connectors)
My MP3 player (and most portable devices) use a  1/8" diameter mini stereo phone jack like your earbuds have.
So you will need a short cable that has RCA on one end and in my case the 1/8" stereo phone plug on the other end.
DON'T GET IT LONGER THAN YOU ABSOLUTELY NEED.  Anything more is just more opportunity to pick up stray noises.

Last but not least, you need to mount the power switch for the FM modulator because when it is on, it wants to be the signal to your FM radio and when off, it passes the antenna through to the radio untouched.
I mounted mine just forward of the radio.  As shown below.

I was able to 'fish"  the  switch wire and switch  up just beside the gas tray and along side the radio without doing more than removing the two acorn nuts jsut under the front of the seat and lifting just enough to pull it through using a small rod to fish it with.

Same thing for the audio wires but they went beside the faux tank and all I did for that was to remove the one special bolt that holds the back of the faux tank cover and acts as a pin for the side cover when pressed on it.
That gave me plenty of room to fish things through without any actual disassembly.

In fact, only the seat and the battery cover had to come off to get the whole thing done.

Takes about 1.5 hours first time.   I could do it all in 30 minutes after that if I had all the tools ready (drill, soldering iron, terminals, etc).

I think it is the best quality for the least effort and everything stays stock except the hole you have to drill to mount the power switch.


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