# 3.5mm to Coax



## ToonMechaMan

I'm looking for the best way to connect any portable device I have (like my phone) up to the coaxial input on my AMP/DAC combo Aune X1S. Due to hardware restrictions I can't use the RCA inputs on the back as you can't use the RCA outputs to output sound to another amp while using the RCA inputs as my your primary source. I've it connected to an Aune X7S balanced output which I'm trying to use with my portable devices.


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## ToonMechaMan

I'm using the HD800 (non-S) balanced for this BTW.


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## ostewart

ToonMechaMan said:


> I'm looking for the best way to connect any portable device I have (like my phone) up to the coaxial input on my AMP/DAC combo Aune X1S. Due to hardware restrictions I can't use the RCA inputs on the back as you can't use the RCA outputs to output sound to another amp while using the RCA inputs as my your primary source. I've it connected to an Aune X7S balanced output which I'm trying to use with my portable devices.



For this to work, your phone will have to output a digital signal, as Coax is digital.

Does your phone output digital out via optical or coaxial? most likely not, so you can't hook it up this way.

You might be able to take the digital out from the USB port of your phone, then to a DAC that converts the signal to coaxial, but more hassle than it is worth.


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## ToonMechaMan

ostewart said:


> For this to work, your phone will have to output a digital signal, as Coax is digital.
> 
> Does your phone output digital out via optical or coaxial? most likely not, so you can't hook it up this way.
> 
> You might be able to take the digital out from the USB port of your phone, then to a DAC that converts the signal to coaxial, but more hassle than it is worth.


Is there some kind of converter I could use to convert the analog signal into a digital signal? Looking for something I can plug a 3.5mm into and have it connect the coaxial input from my X1S.


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## ostewart

ToonMechaMan said:


> Is there some kind of converter I could use to convert the analog signal into a digital signal? Looking for something I can plug a 3.5mm into and have it connect the coaxial input from my X1S.



That won't work,

So you'll have to use a RCA splitter so you can have 2 lots of RCA's going into one input.


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## ToonMechaMan

ostewart said:


> That won't work,
> 
> So you'll have to use a RCA splitter so you can have 2 lots of RCA's going into one input.



So if I were to use a 3.5mm to stereo RCA then connect it to something like this then connect it to my digital coax cable would it work?

https://www.amazon.com/Digital-Optical-Converter-Selectable-Sampling/dp/B0055EBH5S


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## ostewart

ToonMechaMan said:


> So if I were to use a 3.5mm to stereo RCA then connect it to something like this then connect it to my digital coax cable would it work?
> 
> https://www.amazon.com/Digital-Optical-Converter-Selectable-Sampling/dp/B0055EBH5S



That would work, I see you've now changed your original post saying the RCA inputs won't work. Otherwise you could have used these:

https://www.amazon.com/gp/aw/d/B01D...a+splitter&dpPl=1&dpID=411NqoB+fnL&ref=plSrch

The issue of course using the device you linked, the phones headphone output isn't going to be very good quality, so you're going to be converting a bad quality signal into digital and not gain and sound quality improvements, only volume.

Does your phone support audio out via other OTG?


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## chef8489

Why dont you state what phone you have. This would make this a lot easier instead of us trying to guess what you have.


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## ToonMechaMan

ostewart said:


> That would work, I see you've now changed your original post saying the RCA inputs won't work. Otherwise you could have used these:
> 
> https://www.amazon.com/gp/aw/d/B01DRQEYBY/ref=mp_s_a_1_44?ie=UTF8&qid=1498110142&sr=8-44&pi=AC_SX236_SY340_QL65&keywords=rca+splitter&dpPl=1&dpID=411NqoB+fnL&ref=plSrch
> 
> ...



I can't use the RCA inputs on the back of my amp so I have to use the coax input instead which is why I asked about a converter to be able to use the coax input. My phone, which I've two: a Moto X 2nd gen and a Samsung Galaxy S6, do support OTG but I've currently got my amp hooked up to my computer via USB so I'd rather not use that input. I'm fine with simply amplifying the signal. Not sure if you've ever used the HD800 but it sounds different based on what amp you use, more so than any other headphones I've used and my Aune X7S being fed sound through my X1S produces the best sound out of all of the different amp and DAC setups I've used.

My Aune X1S has 4 inputs: 1 RCA input, 1 coaxial input, 1 USB, and 1 optical input. I currently have it outputting the sound via its RCA outputs to my balanced Aune X7S. I can output sound from all of the inputs except the RCA inputs which can only output sound through the X1S's 1/4" headphone out. I figure the easiest way to use my balanced output with any device with a 3.5mm out is through the coax input since it's far more flexible so I can have it out in front of the amp so it's easier to switch devices with compared to having to reach behind the amps and constantly unplugging all of the cables cables. It's a convoluted setup but I do use all of the inputs on the back, except the RCA inputs.


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## Oscar-HiFi

ToonMechaMan said:


> I can't use the RCA inputs on the back of my amp so I have to use the coax input instead which is why I asked about a converter to be able to use the coax input. My phone, which I've two: a Moto X 2nd gen and a Samsung Galaxy S6, do support OTG but I've currently got my amp hooked up to my computer via USB so I'd rather not use that input. I'm fine with simply amplifying the signal. Not sure if you've ever used the HD800 but it sounds different based on what amp you use, more so than any other headphones I've used and my Aune X7S being fed sound through my X1S produces the best sound out of all of the different amp and DAC setups I've used.
> 
> My Aune X1S has 4 inputs: 1 RCA input, 1 coaxial input, 1 USB, and 1 optical input. I currently have it outputting the sound via its RCA outputs to my balanced Aune X7S. I can output sound from all of the inputs except the RCA inputs which can only output sound through the X1S's 1/4" headphone out. I figure the easiest way to use my balanced output with any device with a 3.5mm out is through the coax input since it's far more flexible so I can have it out in front of the amp so it's easier to switch devices with compared to having to reach behind the amps and constantly unplugging all of the cables cables. It's a convoluted setup but I do use all of the inputs on the back, except the RCA inputs.




Use the OTG output of your phone to one of these, then optical to your DAC... hoping it works with OTG that is.

https://www.amazon.com/USB-DAC-PCM2...8&qid=1498146733&sr=8-3&keywords=USB+to+spdif


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