Combining vario and radio output into one speaker

I am wondering if it is possible to combine the outputs of a vario and a radio and send it to one speaker. I did try to Google it, but I did not find a satisfactory answer.

Any ideas please?


Cheers

Paul

Yes in a number of ways, all of them more expensive, failure prone
and space consuming than installing a second speaker !

At 07:20 26 February 2015, Paul B wrote:
I am wondering if it is possible to combine the outputs of a vario and a
radio and send it to one speaker. I did try to Google it, but I did not
find a satisfactory answer.

Any ideas please?


Cheers

Paul

You would need a mixer circuit. Do not combine signals together, you'll burn your audio amps inside radio and vario. Best bet would be to use mixer designed for aircraft (http://www.aircraftspruce.com/catego...diomixer.html), but I'm afraid most of these are designed to drive headsets and do not have enough power to drive speaker. There might be some radios or varios that accept other audio source and have built-in mixer. I installed two indentical speakers for my glider, very simple solution.

Hi Paul,

I highly recommend that you do not try to connect 2 devices to one speaker.
It could damage one or both of the instruments. I have done repairs to
several soaring instruments which had their audio output circuits fried by
doing just this.

Best Regards,

Paul Remde
Cumulus Soaring, Inc.
_________________________________________________

"Paul B" wrote in message
...

I am wondering if it is possible to combine the outputs of a vario and a
radio and send it to one speaker. I did try to Google it, but I did not find
a satisfactory answer.

Any ideas please?


Cheers

Paul

On Thursday, February 26, 2015 at 6:55:00 AM UTC-7, Paul Remde wrote:
Hi Paul,

I highly recommend that you do not try to connect 2 devices to one speaker.
It could damage one or both of the instruments. I have done repairs to
several soaring instruments which had their audio output circuits fried by
doing just this.

Best Regards,

Paul Remde
Cumulus Soaring, Inc.
_________________________________________________

"Paul B" wrote in message
...

I am wondering if it is possible to combine the outputs of a vario and a
radio and send it to one speaker. I did try to Google it, but I did not find
a satisfactory answer.

Any ideas please?


Cheers

Paul

Yes, one does need a mixer or audio panel. Not a bad idea though. If all the electronic noisemakers ran their output through an audio panel, sound levels could be "equalized" and it could have a master volume. Using one, larger speaker with good sound is better than a bunch of little crappy ones.

We would need a special unit for gliders. Airplane units are too big and intended for headsets.

On Wednesday, February 25, 2015 at 11:20:35 PM UTC-8, Paul B wrote:
I am wondering if it is possible to combine the outputs of a vario and a radio and send it to one speaker. I did try to Google it, but I did not find a satisfactory answer.

Any ideas please?


Cheers

Paul

Look into motorcycle intercoms. There are a number on the market, one common feature is combining audio sources such as the other passenger, the stereo, and cell phone. They typically do it in a priority scheme such that the stereo (vario) will be muted or attenuated while the passenger (radio) speaks, when done the stereo ramps back to normal volume. Small box, doesn't use much power, doesn't cost what anything stamped "for aircraft" cost.

Many radios offer an auxiliary input, but
Paul Remde's experience with damaged
units suggests less heartache potential if
you keep them separate.

Now all I have to do is make a more
secure mount for my Vario speaker.

Thanks for all the advice above. I have done some further searching and did come up with some answers.
As I feared it is indeed not advisable to simply connect the outputs together. Whilst it may work, the chance of poor quality sound and indeed damage to equipment is high.
However it seems possible to connect different outputs to a single speaker with some relatively simple passive circuits. If anyone is interested, here are some links:

http://www.rane.com/pdf/ranenotes/Why_Not_Wye.pdf
https://www.gearslutz.com/board/geek...o-summing.html

Perhaps the next question should be. If the mixing is possible from the technical perspective, is it a good idea from the practical perspective?


Cheers

Paul

On Friday, February 27, 2015 at 2:43:35 PM UTC+13, Paul B wrote:
Thanks for all the advice above. I have done some further searching and did come up with some answers.
As I feared it is indeed not advisable to simply connect the outputs together. Whilst it may work, the chance of poor quality sound and indeed damage to equipment is high.
However it seems possible to connect different outputs to a single speaker with some relatively simple passive circuits. If anyone is interested, here are some links:

http://www.rane.com/pdf/ranenotes/Why_Not_Wye.pdf
https://www.gearslutz.com/board/geek...o-summing.html

Perhaps the next question should be. If the mixing is possible from the technical perspective, is it a good idea from the practical perspective?

Sure, of course it's easy to mix signals by adding resistors to prevent drawing excessive current from one output to another one.

The problem then is your loudspeaker won't be very loud.

It can be ok for headphones.

For a decently loud loudspeaker, the result of such mixing needs to be fed into an amplifier. (perhaps a speaker with a built in amplifier, such as those made for connecting to PCs or MP3 players)

For the best results, you also want to put an "op amp" in negative feedback "voltage follower" configuration between the resistor mixer and the amplifier.

The really paranoid will also connect each input via maybe a 1 or 2 uF capacitor, and the same from the output of the op-amp to the amplifier.

You could also put a variable resistor with a knob on each of the inputs as a volume control. And another as the feedback resister on the op-amp as an overall volume.

Now you're getting fancy :-)

On Friday, 27 February 2015 15:05:45 UTC+10, Bruce Hoult wrote:


Now you're getting fancy :-)

Thanks Bruce

The fancy is what I want to avoid, as the initial idea was to simplify things - i.e. one speaker instead of four .

Cheers

Paul