View Full Version : Bluetooth issue.

09-17-2010, 10:03 AM
Hi all, any one here familar with external Bluetooth mics for car stereos? I recently bought an Sony MEX-BT3800U from amazon and the Sony mic is like $20+. I'm trying to figure out if its just a regular 3.5mm jack or what.

After some experimenting I found that the connector labeled "mic" on the back of the receiver looks just like a regular 1/8" in jack, so I went to radio shack and tried out 2 standard web cam type desktop mics just to be sure. No go on either one. Called a friend and she said she could hear nothing when I had it set to external mic, only on internal.
The receiver also has a 1/8" front aux plug which I usually plug in my MP3 player to and it works great, so just to be sure, I plugged the mics into there to. Nothing. Came home and decided to try the only other passive output device I could think of, my 1983 Gibson Sonex 180 Deluxe. Plugged it into the front jack (used to do this in high school) and guitar noise comes out the speakers.

This is where it gets interesting (well kind of). I proceed to plug the guitar directly into the mic input on the back of the receiver, set it to "external mic", and called my bluetooth linked cell with the house phone, head unit answers the call, and on the house phone, I can once again hear the guitar.

So what gives? If these are both passive devices (the guitar has no batteries or anything) why would it pick that up and not the mics?
Could someone with more audio experience please explain this?
I did however prove (I think) that it is just a regular 1/8" jack for the mic.

Sorry for the lengthy post.

09-17-2010, 10:09 AM
the plug might have a different order from standard. Apple is good about doing this so you have to buy their equipment.

09-17-2010, 11:56 AM
Well if the guitar worked on it shouldn't it be standard order? I dont even use apple stuff.

09-25-2010, 12:05 PM
Could be the input impedance. Sometimes a mic could be a "high Z" or low Z input depending on the design. A guitar is usually considered a high Z input. I don't know why it would make a difference, since what you are doing should produce sound either way. Maybe experiment with a variable resistor and see if the impedance makes a difference with a mic?