Hello, I want to connect TV and PC to my speakers and control the volume of both devices with a knob, I know I can use Mackie Big Knob Passive, but I'm wondering if I can achieve the same result with M-Audio M-Track 2x2M (or newer Air 192/6) as it has two line-in inputs. Will it work if I connect L & R channel output from TV to the inputs in M-Audio and then just switch between PC and TV source with USB/Direct knob?
Few TVs have analog audio outputs so that might be a problem. Most TVs have digital audio outputs (mostly optical). You could use a digital to analog converter to provide an analog audio output from the TV.
The M-Audio should work since it has zero latency monitoring.
You may get better sound from the PC than using the Knob if the DACs in the M-Audio are better than the PCs'.
The Knob is probably simpler to use since it have fair fewer functions.
Any stereo preamp will work if you use analog from the PC and TV.
Thanks for your reply, I'm already using Fiio D3 to convert optical output from TV to analog and connect directly with the speakers, but then I have to use speakers knob to control the volume. I also have M-Track 2X2 that I use with PC but it has only one line input, I tried to play music from phone, it works but it sounds like one channel is missing, so I guess it's mono. That's why I'm thinking about replacing the interface, if I could connect left and right output from Fiio D3 to M-Audio inputs, it will be great.
But I think the inputs are for recording purposes to connect a guitar or mic, that's why I'm afraid it would not work.
Since the M-Audio is for recording it does treats each input separately. When you use it with the phone you don't get mono. You get either the left or right channel. Depends on how the stereo plug works with the mono jack.
You would have to monitor 2 analog inputs at the same time for the TV and use the USB to get audio from the PC.
Easier to go analog and maybe better sounding too.