random things and thoughts … and bad ideas
2 seats 1 amp
2014-12-28Posted by on
Apparently I have a thing for finding problems normal customers don’t see. Or maybe normal customers just accept things as impossible earlier and move on. One of these problems is my audio setup in the living room. There is an audio/video receiver sitting right beneath my 40″ screen accompanied by a center speaker and one speaker in each corner of the room. With my couch facing the screen this setup is what you want for watching movies and playing console games on the big screen. At the wall to the left of my couch though is a desk for my PCs where I sit most of the time working, doing web things or playing games. So when I sit at my PCs the front speakers are to my right and the rear speakers to my left. And this is where my pain begins.
The main goal I have with this setup is to play Windows games on my PC with surround sound and additionally using a headset when I’m playing with friends. The additional headset part is not that hard. I just got a cheap bluetooth headset and connected it to my Linux box so it works independently from the audio on Windows. On the other hand fixing the channel assignment on Windows with changed speaker positions turns out to be pretty hard. I had this somewhat solved two years ago but now that my AV receiver decided to kick the bucket I am once again faced with this whole mess. There are several different approaches I could think of to solve all this but each of them has its own set of problems.
analog multichannel input with a twist
The most trivial solution and what I’ve been using so far is connecting the PC via analog multichannel connectors to the receiver. Every channel has its own RCA connector so the channels can be reassigned freely by just connecting the RCA jacks to different connectors on the receiver. While this is a pretty simple solution it does not come cheap anymore. Since the broad acceptance of HDMI analog multichannel input is slowly fading out of existence. Even back when I bought my current AV receiver it was one of the uncommon models that had analog multichannel input and now two years later the only models that still have it are in the high-end class for a thousand bucks or more. Of course there’s the option of buying an older model second-hand but honestly I don’t trust used electronics especially if they’re going to be central parts of my living room setup.
changing the channel map
If using the hardware to change the assignment of speakers to channels is not viable I could just change the assignment in software. After all with HDMI everything is digital until it reaches the DAC in the receiver so changing the mapping of channels to speakers should just need flipping some bits, in theory that is. I looked into changing the mapping of channels in Windows or the drivers but couldn’t find anything. I looked into configurable virtual audio devices and did indeed find some used for looping audio back to other devices but none of them allowed changing the channel map. I know remapping the channels is easily done on Linux with ALSA or PulseAudio and I expected it to be possible on Windows in some way too but I guess Windows was made for those normal customers mentioned earlier.
The source is not the only place where the mapping could be changed. Just like with the analog cables the receiver could rearrange the placement of channels during digital processing. But I have yet to see a receiver that offers this kind of feature and I’m sure if there are any they’re going to be in the high-end class too so it wouldn’t save me any money.
Alternatively the signal could be changed on the way to the receiver by plugging some box between the PC and the receiver to mangle the channel mapping and pass the manipulated signal on to the receiver. Even if there are some existing solutions for this I doubt they come cheap and building something like this from scratch would cost way too much effort and money so this is a rather theoretical approach.
There’s also a generic problem with all these methods. There are four speakers one in each corner. But there is only one center speaker the one between the front speakers. Even if the assignment of the speakers in the corners gets changed the center speaker would not move. So at the PCs I can’t use full 6-channel 5.1 audio but only a 4.0 configuration. But this is just a minor issue I could live with if it was the only one.
Changing the channel map doesn’t seem feasible. A completely different approach would be to make the surround sound experience independent of the listening position. This is possible using headphones or a receiver that support Dolby Headphone. This technology takes the 5.1 signal, applies some filtering magic that makes use of how we get spatial perception with just two ears and creates a stereo signal which, if played directly to the ears, delivers a similar experience to sitting in the sweet spot of a 5.1 speaker set. Because headphones usually sit on the head and turn around with it the direction I face or my listening position wouldn’t matter at all. Most modern AV receivers should support Dolby Headphone or at least something comparable so that would solve my issue with speaker positions. Still it does introduce some new problems. I can’t use my bluetooth headset under the headphones so I have to buy an additional gaming headset or single microphone which I won’t do because I already have good headphones and a mic in my bluetooth headset. Also I got this feeling that using a 5.1 speaker set would be more immersive than having virtual surround via headphones.
A more fundamental way to address my issues would be taking care of the two different seats. If I could play PC games in the same position I watch movies and play console games there would be no need for fiddling with the audio configuration at all. I could either start playing PC games sitting on the couch having the mouse and keyboard on my couch table or rearrange the whole living room so the big screen and the PC monitors are next to each other. Both variants don’t sound very appealing. I’m not sure if I really want to play PC games at the couch table and I do like where my furniture is now.
After considering all these options I haven’t found anything that would solve all major issues without introducing new ones. Of course there are a lot more options how I could theoretically handle this like installing another 5.1 speaker set just for the PC or giving up on surround sound for games completely but I won’t really waste time thinking about these. So here I am pondering what direction I should take with non of them leading towards a clear solution. I’d be glad if someone had some new ideas I did not see myself and could leave me a comment. You could also use the comments to mock me for not being able to compromise but be warned you will earn my never-ending spite.