Question about audio interfaces

Here’s my use case:
I want to play guitar and listen to a song playing on the PC (either youtube or local music player) at the same time through headphones, so I don’t make too much noise after everyone went to bed.

Someone recommended to me to buy an audio interface:

I’m not sure that this will work as I expect. It can be plugged into the PC, but all how-to articles and videos I found said the headphones should be connected to the audio interface but I don’t see how the audio from the PC will be sent there. If I was to connect the headphones to the PC, would I get the sound from both the guitar and the PC?

I’m not sure, but I just got one of those focusrite interfaces for my daughter, so I can test later. Would you be connecting to a Mac or PC?

You should be able to plug the headphones directly on the audio interface

Normally they are just USB sound cards but it looks like this one accepts a (guitar) input and works as a mixer

Yeah page 12 of manual has that use case


Hmm, it’s unclear if I’ll be able to hear audio from the PC.

I have one, yes, 100% you can hear audio from the PC, as well as audio from the inputs.

You can use it as an in ear monitor to hear levels when recording voice (what I use it for)

You set your sound input in windows to output to Focusrite Scarlet, and it outputs to the device.


This jack will output both monitor from the inputs, as well as PC audio. The dial to the left will change the volume of all at the same time. You can use the input knobs to adjust their volume, and your PC output to speakers to balance.

I don’t love that it doesn’t have a separate knob for the PC input, but it is plenty functional, because adjusting the PC output volume via windows isn’t great, but it certainly works.

Looks like if you want to spend more, the 2i2 has the ability to adjust the usb speaker output with a knob.

OK, so:

Yes, these interfaces will play sound from the PC back from the monitor/headphone jack. They’re basically a fairly high-grade sound card, with multiple inputs and physical controls, designed for recording from proper PA gear. See that “Direct Monitor” button? You’ll always get the sound from the PC coming out of your headphones, and that button will toggle whether you also hear the inputs mixed in. Of course as with any PC that has multiple sound cards, you’ll have to pick which one windows uses.

The Scarlett 2i2 doesn’t have a separate volume for the PC - that extra knob is so that you can control the headphone and monitor out volume independently (On the back they have jacks to connect to speakers and the cheapest version ties the headphone and speaker volumes to a single knob.) Its major benefit is having 2 combo plugs which can take either XLR or 6.5mm (1/4") jacks, so you have more flexibility in which devices you can plug it to record from.

I’m not aware of a simple audio interface with the ability to control the level of the PC separately, though there are higher end devices focused on podcasting or streaming which do.

Another solution to your issue could be the amPlug 2, which allows you to plug in an aux input through a 3.5mm jack, plugs directly into your guitar, and unfortunately still doesn’t have independent volume for both the aux and guitar. Uses AAA batteries though, so you’d want to have NiMH rechargeables, while most smaller interfaces will self-power from the USB port. On the other hand, this could be used far more portably with a phone as the music source. You can do that with an interface as well, but not all interfaces play well with mobile devices, so you’d probably want one designed for the purpose.

There is a cheaper option. Get a Rocksmith Guitar cable and use regular headphones or even a usb headset if you have one. This is what I do.

Thanks guys, I did end up getting the Focusrite 2i2. It works great.

I used to have one of those but it didn’t fit will in my guitar socket. I looked closely and saw that the edge is a little different to regular jacks. I jammed it in and ended up breaking it when I tried to take it out again. I wonder if Rocksmith will work with the Focusrite. Probably not but I’ll give it a go.