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External Audio

gblwy

gblwy

Well Known Member
I plugged my iPhone into the external audio socket. The volume through the intercom is very low when everything else is set to a satisfactory volume. Do I just have to live with that (or swap my Bose for the new ones), or can something be tweaked somewhere?

Thanks for any help...Keith
 
Volume with iphone

I have been trying to install a setup that can utilize my iPhone music and my xm radio. The iPhone is louder than the XM but both are still inadequate. I am going to meet with an audio guy later this week, I will let you know if he has any answers. Good Luck!
 
You may need to add this...

I have never tried this through an audio panel but it works on motorcycles.
It might be worth a try.
http://www.aerostich.com/super-booster-motorcycle-amplifier.html
I think this would solve your problems the cheapest and simplest but I am not 100% sure.
This one would allow for XM radio, iPod, iPad, ect.... inputs http://www.aerostich.com/mix-it2-multiplexer.html

If you are charging at the same time and get some feedback while listening to music you may have to add this: http://www.crutchfield.com/S-cvuI5yjrld5/p_127SNI135/PAC-SNI-1-3-5-Noise-Filter.html


I bet this guy has your answer as well. His amplifier is more expensive but appears to have filters and everything built in.
http://www.vx-aviation.com/

Tim just did an upgrade to his RV-10 and I know he really likes it.
http://www.myrv10.com/N104CD/upgrades/20101228/index.html
 
Keith,

The music jack and the GPS sound are connected in parallel and go directly into the intercom. If the GPS volume is OK, then the iPhone volume is not loud enough. Something like this stereo amplifier might help: http://www.maplin.co.uk/universal-stereo-pre-amplifier-22671
or this: http://learnelectronics.co.uk/index.php/products/project-kits/ic-based-kits/mp3-stereo-amplifier-kit/

There is an unused audio input for the control board audio amplifier but it is mono only. To use that, connect a wire to pin 4 of the Transponder D-Sub on the back of the control board. There is a pot above the D-Sub for volume adjustment.
Joe
 
Probably different impedances....I built an impedance matching device for about $20 or so to bring a MP3 player up to the same level as the XM radio installed in my plane.

Here is the solution I used and am very happy with. Here is what it looks like inside:

N521jl-volfix-image002.jpg


N521jl-volfix-image003.jpg


Mike
 
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Apple devices sending weak signal

FYI I have the same problem in my truck, I run my IPOD into the AV inputs in the entertainment system. Their is some kind of switch that determines there is input coming in to allow you to select the Aux input in the dash controller, if the IPOD is not all the way up it doesn't process the signal. Looks like the impedence matching issue might be it.

Anyone measured the output from an apple device?
 
I find that if I'm using the headphone jack to supply anything, my iPhone volume control still functions normally. I need to turn it up near full volume for it to behave more like a "line out" to feed my intercom. Same is true for my iPad.

If you hack into a dock connector you can tap into the actual line out signal from the iPhone/iPad, and use that instead. No, I haven't bothered trying it either... I just use the headphone jack.
 
iPhone/iPod/iPad

I would not think that the iPhone would be any different than the iPod/iPad in terms of providing an ample signal via the headphone jack (without the need for additional amplification). I have used both an iPod Touch and an iPad in my -12 without any difficulty. Just need to have the volume on the iPod up high enough.

Jeff
 
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From the Cirrus Owners and Pilots Association article on the subject:


"The consumer electronics industry has standardized to an impedance value of 8 ohms, while the avionics industry has standardized to an impedance value of 600 ohms. While neither is particularly better or worse than the other, they are indeed different. The end result is that power will be lost when a consumer electronics device (with its 8 ohm standard) is plugged into the audio jack on your avionics panel (with its 600 ohm standard). And lost power equates to lower volume."

The impedance matching device works for me. I would imagine some newer audio panels would resolve this mismatch; they know that consumer devices are to be plugged in. Not so on my Garmin.
 
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SpyderMike said:
From the Cirrus article on the subject:


"The consumer electronics industry has standardized to an impedance value of 8 ohms, while the avionics industry has standardized to an impedance value of 600 ohms. While neither is particularly better or worse than the other, they are indeed different. The end result is that power will be lost when a consumer electronics device (with its 8 ohm standard) is plugged into the audio jack on your avionics panel (with its 600 ohm standard). And lost power equates to lower volume."

The impedance matching device works for me. I would imagine some newer audio panels would resolve this mismatch; they know that consumer devices are to be plugged in. Not so on my Garmin.
Click to expand...

If Cirrus said this, then they are guilty of techno babble. An 8 ohm output driving a 600 ohm input will lose very little power. Also, the consumer electronics industry has not standardized on an 8 ohm output for portable music devices. 32 ohms is more typical. These numbers are also not necessarily the output impedances of the driving device, merely the load impedance that they are designed to drive. Typical output impedances are much lower.

The problem is the amplitude of the signal. The so-called impedance matching transformers actually boost the signal amplitudes, but have very poor frequency response and may lower the music quality.

The best solution overall is to use a proper intercom or audio panel that is designed for low-level audio inputs (such as from an iPOD). If your intercom or audio panel does not support this, then check the vx-aviation.com website for some gizmos that do the trick.

Thanks,
V
 
Cirrus did not state this and are not guilty of techno babble. A Cirrus owner is (previous post correct to identify source of the statement). The Garmin 340 in my plane does not support low level audio input, therefore the use of an impedance matching device. It works just fine - audio quality and all. Thanks.
 
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SpyderMike said:
Cirrus did not state this and are not guilty of techno babble. A Cirrus owner is (previous post correct to identify source of the statement). The Garmin 340 in my plane does not support low level audio input, therefore the use of an impedance matching device. It works just fine - audio quality and all. Thanks.
Click to expand...

Odd. If Garmin is providing a music input, you'd think that it would actually work with common music sources. Have you spoken to Garmin about this? They have a mod to boost the music level by 20 dB (Service bulletin 0113).


V
 
If you're into electronic do-it-yourself projects, several years ago I built a preamp called the "Headbanger Amp" for boosting the output of my portable MP3 player to drive a SoftComm intercom's music input. It's cheap, works perfect and sounds great.

Here's the URL for the project, which is made from parts from Radio Shack. It cost me about $25 for the parts to build it back then.

http://www.minidisc.org/headbanger.html

The website even has a link where you can buy a ready-made version of the amp for $99
 
Boost volume of both iPhone and xm

when I plug my iPhone directly into my audio it is louder than my xm. The xm is coming in on a garmin 696. The iPhone is about 2x the volume of the xm on the 696. To sum it up here is what I am trying to accomplish:
1. Be able to use either xm or iphone
2. Have volume of both louder

Thanks for everyones input so far, also for the record I have a Garmin 340 audio panel.
 
Garmin has a computer program to make internal adjustments. If you google "garmin 340 gma configuration tool" you will see that there is a page in the install manual showing the screen shot of a volume adjustment configuration screen. If you have the right cable adapter or have an avionics shop near by - with the Garmin setup, then you might be able to have the signal boosted to you liking.

Mikr
 
SpyderMike...........

you are the Man! I went down to Radio shack and made up the device according to your schematic. It works perfect. Plenty of volume from the ipod & Droid. I had tried using amps in the past to no avail. Your little device really works. Thanks for solving this nagging problem.
 
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