[Kinda solved] How to turn one audio port (on iPhone or Mac) into two (input and output)

Other Gear
#1

Hey pals!!


So, I’ve spend the last couple of days researching a lo-fi / budget way to turn the single audio port in my iPhone and/or MacBook Pro into two ports—one input and one output. This would be for quick jams using my op-1 and a line into my Mac or iPhone to record into a DAW or something while also listening in headphones (super handy on the train or airplane!)

Now there are a ton of splitters (like this one) that claim to do this, and are designed work very simple. They just split the signal or something using the same idea as your headphones with in-line mic combo. Based on the reviews, they work pretty well. However, when I purchased mine, the input would not work, only the output. Now, I dug up an obscure review from someone who claims that Apple has a different standard for inputs, and he solved the problem by soldering a 1500 ohm resistor to a male to female audio cable, essentially making an adapter, and that solved the problem.

I don’t have access to a soldering solution, and to buy one would make this project cost more than it’s worth. I do know there are things called impedance adapters that would do what I want, but I can’t seem to find any that are around 1500 ohm range, only in the low hundreds.

Anyone have any tips or ideas on where to go from here? Also, what the heck, why doesn’t a cheap budget device like this exist? A passive splitter for iPhones and Macs that just turns my humble little audio port into two? Seems weird to me. It’s also possible I’m doing something wrong and this is easier than I’m making it out to be.

Anyway, thanks in advance!

edit: as @docshermsticks explained, this can be accomplished by either buying a different splitter that fits the standards of your phone/computer, or buying an adapter. I was SORTA successful in getting my iPhone and my Mac working with an input and output by using this adapter from amazon. The main problem is, it really depends on the order in which you plug the devices in and maybe the order in which you power them on. I get seemingly random results depending on how I plug everything in, from loud feedback, to a little noise, to perfect sound with no noise. Not sure if I’m going to keep this solution, your mileage may vary :slight_smile:

#2

the TRRS splitters should work as is. i have a couple and have used them on my iPad and iPhone w/o issues.


it is true that there are different wirings for them and no real standard across the board which kinda sucks.
they are pretty cheap tho so not the worst thing to burn.

i think the thing that makes it hard is that there are a billion different kinds of these
that all pretty much look the same even tho they may not be
with little to no detailed explanations or specs.

this kinda breaks down the different conventions for u
http://www.cablechick.com.au/blog/understanding-trrs-and-audio-jacks/


#3

I’m aware of the TRRS splitters and that they should work… but it seems like a lot of them dont(?)

but you’re saying that some should work out of the box? hmmm, interesting, guess I gotta keep rolling the dice to see which one works haha
what’s weird is that for many of these, 80% of people will state it won’t work with their iOS device, yet there will be a few who say it will.

edit: wow, that site you posted is fantastic, thank you! I may try that adapter, or just buy a splitter from them. thanks so much! !
#4

@docshermsticks thank you so much, this was the answer I needed. I was distracted by that weird impedance thing I read about, and the problem is probably just the CTIA/OMTP standard detailed in the article you linked. thank you thank you!!! <3