I was aiming for no parallel walls,
But your actual walls are still parallel! You are only angling the TREATMENT that is inside the room, next to the walls. It's also a myth that walls have to be angled... They don't, unless there's a very specific reason for doing so....
I can change the angles of the speaker soffits and modify the side walls easily enough.
That's why I asked - so that someone who has more experience will prod me in the right direction.
Fair enough!
What I would suggest is that you should first choose the overall design concept for your room. There are many different concepts for control room design, and each has it's own specific specifications, methods and techniques. For example, 30 years ago the LEDE concept was used widely, where "LEDE" stands for "Live End - Dead End". The room was built with the front end totally dead acoustically (highly absorptive, broad-band) and the rear end very live (highly reflective). There were good acoustic reasons for that concept, but it turned out to be very unnatural to mix in, and fatiguing. So nobody builds pure LEDE rooms any more. There are many other concepts these days, some of them extensions or modifications of the LEDE design, some using totally different concepts. So you should first define what the purpose of the room is, how accurate you want it to be, how you will use it, and then settle on the design concept that best fits your needs.
So you'll need to do a bit of research on concepts such as RFZ, NER, MR, CID, and others, to figure out which way you want to go. Personally, I'm a huge fan of RFZ, and almost all of the rooms I design are based on that, since in my opinion it's the best one out there right now. Maximum accuracy, cleanest sound-stage, broadest stereo image, tightest bass, least artifacts, etc. But more complicated than the others to design properly.
I will be running everything from a PC hidden in one of the soffits,
How will you deal with the heat issue? This is often overlooked, but there's a very real effect to having hot air flowing up in front of the speaker. It distorts the sound, in exactly the same manner as hot air rising of a hot road distorts the view. If you do want to mount a major heat source, such as a PC, amp, or other piece of gear, in your soffit, then you'll need to deal with that problem: the heat cannot be allowed to rise in front of the speaker.
Also, if you use the space inside the soffit for a PC, then you will be eliminating that space for use as acoustic treatment. The areas above and below a soffit-mounted speaker are extremely useful locations for acoustic treatment. If you use those for something else, then you will need MORE treatment in other parts of the room, to make up for the lost effect. And since room corners are the most effective locations for treatment, if you put treatment elsewhere, you will need a lot more of it.
and both my mixer and DAW are remotely controllable by iPad
Where will the mixer be located? Outside of the room, I guess, based on what you say?
rather the plan is to kick back on the couch or one of the wingback chairs (the furniture can be easily rearranged) for mixing, etc.
Question: How do you plan to mix if you are not in the sweet spot?
Think about that.
The entire purpose of a control room is to create the best possible acoustic environment at one specific location in the room, so that the engineer hears only pure, clean, unmodified, perfectly balanced, perfectly smooth sound at his location. It is only possible to achieve that for one point in the room: the sweet spot. All other points in the room have less pure, less clean, colored, unbalanced sound. If you sit on the couch or in one of the easy chairs, then your head will be "off-axis" to the speakers, so you will not be hearing them both equally. If your head is above or below the acoustic center of the speakers, you will not hearing the direct sound. If you are too far back in the room, or too far forward, then the sound field will be distorted in one way or another, enhancing some frequencies while attenuating others, as well as having artifacts on the time and phase domains.... You cannot easily and successfully mix if you are not in the sweet spot.
There's a reason why control rooms all follow the same basic pattern, with the same general layout: because that's the only one that works! I'm sure it would be nice to sit over in the far corner with your feet up, and mix from there, but that isn't realistic at all. There is always uneven bass distortion in the corners of the room, even a well treated one, and being so far off axis means you wont even be able to HEAR the stereo image, let alone mix it.
I'd really suggest that you should follow the conventional layout for your room, and set up a chair at the sweet spot, so you can track, mix and master successfully. You can get a really nice, very comfortable chair if you want, and you can go without a desk in front of you (although you'd have no place to put your coffee mug, or rest your iPad when you aren't using it....), but the mix position still needs to be in the optimum location.
Here's a graph that very clearly illustrates the problem. This shows a series of frequency response readings that were taken at many different points in a control room, part way through treating the room. You can clearly see the vast range of "sounds" that the room has, depending on where you are sitting in it. All of those readings were taken at the same height above the floor (ear height of a seated mix engineer), on the front-back center line of the room, and at various points between the front wall and back wall. So this is a very controlled test, in a partly treated room that was specifically designed as a control room, and even so there's a huge range of variation just from sliding back and forth along the center line.
walking-mic-example.png
Take a look at around 130 Hz: at some locations in the room, those frequencies are up around 95 dB SPL, while at other locations they are down to only 55 dB SPL. That's a difference of 40 decibels! In other words, at some points in the room 130 Hz is EIGHT TIMES LOUDER than at other points. Could you mix properly, if you happened to be seated at the wrong spot? Obviously, no. Not a snowball's chance in hell!
I often do these tests in rooms to help find the optimum listening position, before finalizing the treatment and room tuning.
Now, that shows the huge variation along one specific, carefully chosen axis of the room, where every effort has been made to get the response as flat as possible: imagine how bad it gets over in the rear corner, where no effort at all has been made! There's no way you'd be able to mix accurately if you are not seated in the sweet spot.
This space is more than a control room, it's also essentially a "man cave" where I'll be hanging out, having whisky and cigars with the band/other friends, listening to some vintage vinyl, etc.
I hope the "cigars" part was just a joke!
I mean, it's your room, for sure, and you can do what you want with it. But if you have any respect for your expensive equipment, then you'll do what most studios do: ban smoking in the control room. To get an idea of how this plays out, take a look at used professional audio gear on e-bay, and see how many of the items clearly state "only used in smoke-free environment". Compare the prices for those against the prices for the exact same model that does NOT say it was used in smoke-free environment... I think you'll get my point.
Many high-end studios do also have a "green room", where musicians, artists, WAGS, engineers, producers, etc. can hang out, smoke, eat pizza, get drunk, throw up on the floor, and do all the other things that they do. But NOT in the control room! It is called a "control room" for a reason: it is a precision room, with tightly controlled parameters, where accuracy is worshiped, and expensive gear is enshrined. Not a place for cigar smoke.
It would also give the band a comfortable place to hang out and listen while one member is tracking individual parts in the next room.
That's what the Green Room is for. Not the control room.
It seems to me that you might want to reconsider your design, and add a green room to it. A control room can be used for other things than just a control room: for example, as a home theater, or for tracking vocals, perhaps acoustic guitars, and some other instruments, or as an audiophile listening room, or a TV room, etc. But NOT as a green room!
- Stuart -