Mono to stereo

[intoflatlines]

How would I make an 1/8" mono male to 1/8" stereo female adapter cable?

Should I buy a 1/8" mono and take the signal and bridge the left and right channels on the female stereo jack?

I don't know anything about how mono jacks are set up, but I have heard that if you plug headphones into a mono jack, sound only comes through the left channel? So, if I made this adapter, I would be able to listen to that same signal only in both left and right channels?

The reason I want to do this is because I am looking for a cheap, small/portable AM radio to take to baseball games this summer with my girlfriend and we like to listen to the radio play by play at the same time. The particular model I'm looking at only has mono headphone out, so I am thinking that I could make this adapter and take a cheap set of IEMs and split the cord (or make the split section longer) so that we can use one set of IEMs (one driver per person) and not have to use an extra Y splitter. Am I heading in the right direction with this? Thanks!

 

[DolbyR]

I wouls bridge the two channels with a 5k - 10k resistor, a 1/8w will fit inside the jack casing. I've sone this with the 1/4" mono to 1/8" stereo adapter to connect my guitar to the PC soundcard.

 

[intoflatlines]

What is the benefit of bridging the channels with a 5 kohm - 10 kohm resistor?

 

[DolbyR]

Quote:

a better way would be to use a stereo plug but instead of just connecting the two hots together use a 5-10K 1/4 watt resistor from the left and right channel "hots" to the new common hot.Small enough to add right inside the plug shell.

That's the original advice I got from Rickr42. Can't say whats the benefit though.

 

[Negatron]

Quote:

Originally Posted by intoflatlines /img/forum/go_quote.gif What is the benefit of bridging the channels with a 5 kohm - 10 kohm resistor?

You are preventing the output of one amplifier from directly driving the output of a second amplifier. Output into output is not a good thing. The resistors present a load to both amps which are then combined...

 

[intoflatlines]

Hm.. So would a 5 kohm or 10 kohm resistor be better?

 

[TMM]

resistors are not required in your situation (1 amp powering 2 drivers)

 

[intoflatlines]

So resistors are suggested when bridging L/R channels in a stereo output to a single driver, but not suggested/required in my situation (mono out jack w/ stereo plug to two drivers)?

 

[intoflatlines]

Bump.

I am opening the radio case right now with the intent of taking out the stock mono jack and putting in a stereo jack, with the mono signal lead from the radio going to both left and right channels on the jack. Am I doing it right?

 

[dgbiker1]

Quote:

Originally Posted by Negatron /img/forum/go_quote.gif You are preventing the output of one amplifier from directly driving the output of a second amplifier. Output into output is not a good thing. The resistors present a load to both amps which are then combined...

I don't think that would apply in this case, since this is Output into Load instead of trying to go stereo>mono where you would have two outputs to 1 load.
I think adding a resistor might make things worse since it will increase the current the mono amp has to supply, which could already be underpowered as it's now driving twice as many loads.