John Sayers' Recording Studio Design Forum Archive

Any opinions on this design?

I am having a hard time deciding between the two (12 and 13 that is)...

Been reading more in the MHoA...the section on modes within splayed walls is scary to me!! Makes me want a nice and easy rectangular room built to a tested ratio! haha... I'm mainly worried about the asymmetrical section at the rear end of the CR in layout 13. Seems like it might cause problems attaining an even distribution of modes based on "my" understanding of the reading . And there's no way to test it beforehand! I'm becoming haunted by acoustics...day and night!

Stuart, I know you had said a notch like that wouldn't be an issue as long as the front was symmetrical. Any change of heart in that regard? Also do you think the CR in layout 13 could sound better than layout 12 since it upholds a true 20ms RFZ? Or am I splitting hairs?

Also any thoughts comparing sight lines? Flow? Comfort?

Ahhhhhhhh so many compromises every which way. I really like certain aspects of both designs.

Thank you all for getting me this far in the journey...I'm just ready to find "the one" and settle down! But there's so many fish in the sea... (speaking of designs here )

Trevor

Both of those like like they will work fine. You have good sight lines in both, nice size and shape of spaces, etc.

I wouldn't worry too much about the modal issue: Everest also says that for rooms that are only slightly non-rectangular (such as yours) you can estimate the modal behavior by averaging the dimensions. Besides, modes can also be attenuated with suitable treatment, and a recent study I read on hundreds of high-end control rooms around the world implies that many of them do have modal issues, to one degree or another. So don't get too hung up over "golden" ratios and "perfect" modal spread: Even if they are spread perfectly, they still need damping!

I'm becoming haunted by acoustics...day and night!

He he he!! Welcome to the club! You are now fully qualified to design and build your studio.....

Stuart, I know you had said a notch like that wouldn't be an issue as long as the front was symmetrical. Any change of heart in that regard?

Perfect symmetry all around is great if you can get it, but the most critical part of the room is the front half. That's where the first reflections are happening, where your ears are, and where the speakers are. Further back is where major absorption and secondary reflections should be going on, with those also being directed into absorption, or diffusion. The concept is to have only a direct sound field in front of you, and develop only a diffuse sound field behind you. If it can be evenly diffuse, then great. If not, then aim to attenuate it as much as possible. Your offset at the rear won't make it 100% "evenly diffuse", due to the lack of symmetry but is sure does look like you plan to kill the entire back end with major, deep absorption: From the shape, I'm guessing that you are thinking of hangers and superchunks back there? Good choice. You have enough space, so that should work well. In fact, you might even be over-doing the absorption back there! That's not just killing a few lows a bit: that's a downright murderous massacre of the entire spectrum going on back there!!!

Now, if you are REALLY concerned about the rear end of the room, and would love to make it "perfect", then just slide the bathroom over a couple of feet, and continue that left wall all the way back at the same angle: It should end up more or less where the toilet is at present, so you'd have to slide the bathroom over by maybe 2 feet.

And if you really wanted to be even more perfect, you could angle the entire rear wall to be parallel to the front wall, or maybe just angle the left half, but either way making the room totally symmetrical again. (That would open up a small triangular space behind the control room, which you could maybe use for a strangely shaped closet in the bathroom...)

Also do you think the CR in layout 13 could sound better than layout 12 since it upholds a true 20ms RFZ? Or am I splitting hairs?

They way you have that laid out and what I'm assuming is deep bass treatment on the rear wall, should give you excellent RFZ. That rear end looks like it will be very dead, and you'll probably have to tune that to not kill the highs too much, but it certainly looks like you are ticking all the right boxes.

However, having said that: 20ms for the Haas effect is only an average estimate for the general population of humans on this planet. For some people, 20ms is just fine, for others as little as 10ms might be good, while still others would still not be getting it at 30ms. So yes, shooting for a perfect 20ms is maybe splitting hairs a little. If it was 19 or 18 it would probably still be good, and I've seen some recommendations saying that a "15/15" criteria is still acceptable for studios, for most people (15dB down, and 15ms late). So this is like ratios: there's no such thing as "perfect", so just get it as good as you can.

Ahhhhhhhh so many compromises every which way. I really like certain aspects of both designs.

OK, that settles it! You are most definitely qualified now! You have passed the final test for home studio design, and you'll be receiving your decoder ring and instructions on the secret hand-shake by mail next week.... !

Seriously, I think it's time to stop sweating these things too much, and start fleshing out your model now, so you get yourself even more confused as you take things into 3D, and start designing your treatment, HVAC, electrical, door seals, etc....

- Stuart -

Thanks for the reply Stuart!! Your input always helps me keep moving forward!

Here is the updated layout. I'm liking the CR better now that it is completely symmetrical from front to back (I think now I can sleep at night ). I have some questions regarding the bathroom walls, however I don't see much need to get into it right now since I haven't begun the 3D for this layout. It's mainly an issue of what to connect the RC to in that space where there is no framing behind the back left wall of the CR.

I think this might be the one. After fixing the CR, I was surprised to find that I only lost about a foot of length on the storage room. Also, there is a great place for some storage in the bathroom where that angled wall is.

Does that look like a more reasonable depth of hangers/absorption on the rear wall? It's 2'6" from the middle point...and a little less than that once it reaches the side walls (about 1'8"). I realize this is not that important to figure out exactly right now, but at least I have a good place to put some hangers!!

I'll post more soon...heading to a friends birthday celebration. Happy Thursday!! And thanks again for all the help. I'm feeling better now...

Cheers
Trevor

Hey Stuart...my builder presented a slight concern for the 1" gap between the inner walls...is it ok to do this? Have people been successful with only 1" between adjacent wall frames in a double wall structure? If I go more than 1" then I will have more than a 12" air gap which you had told me would not be necessary...

Just wanted to ok this small detail since I am now going to work on the 3D...and since sketchup is so hard to reverse and make changes I just want to get it right the first time...or at least as close as possible.

Thanks
Trevor

my builder presented a slight concern for the 1" gap between the inner walls...is it ok to do this?

Why is he concerned about that? Is there some specific issue about it that worries him? Maybe something to do with your local building code?

Also, you are building your walls "conventionally", and not "inside-out", right? If you were doing them inside-out then you'd need more space to fit in two layers of 5/8" drywall and to get an air gap over 4", but for conventional construction a 1" gap between frames will leave you with nearly 9" of air gap. Unless you need very high levels of isolation down to very low frequencies, I don't see a problem with that. Of course, increasing the gap will help with isolation, for sure, but it also eats up floor space inside your rooms... (I'm assuming 2x4 framing here: if you are using 2x6 then the gaps are even larger).

Maybe your builder could be more specific about his concern?

- Stuart -

Hey Stuart thanks for such a quick reply...

He has never built double walls so he was just worried about it being too close to even build (I guess 1" just doesn't sound like much room for error to someone who's never built double walls)...but honestly I'm not really sure what exactly he was worried about (I'll have to ask him again)...it doesn't seem like 2" would make it any easier though.

Anyways, I am using 2X6 studs for the inner walls with 24" OC....that's what is represented in the 2D sketchup. With a 1" gap, that will give me a total of 12".

Thanks for the reassurance...I will continue with 1" since it is all I need.

Cheers
Trevor

Ahhhh....I have some very unfortunate news regarding layout 13.1...it's not even close to a proper RFZ because I overlooked the reflection points on the side walls at the front of the room. The splayed walls are not steep enough to deflect the sound to the back of the room.

I feel so stupid to have missed this!! Ahhh I was about to start working more on the 3D but decided to double check my reflection times one last time and that's when I realized my oversight.

Anyways...on to more designs...yet again.

I thought I finally had it!! So frustrating...

Out for now (and by out, I mean banging my head against a wall )
Trevor

Ooops!

- Stuart -

Ok... Once again I'm back with a new design! Haha

Alright so here it is...basically just an adaptation of the last one. After spending a lot of time trying out alternate footprints with the concrete, this basic rectangular footprint still works out the best for what I need. It also avoids having more than one roofline. This will help out on the cost and speed of construction of the outer shell...so I'm sticking to it. Realize though, it is slightly different considering the last one was a perfect square but it remains approximately the same square footage.

Some thoughts/questions:

-After calculating the RFZ, it comes out to a little over 20ms! (in a 233sq ft. CR)

-How far behind the engineers head should the closest reflections from the side walls be? What's the safe zone?

-Do the baffles of the soffits count as the reflection surface when calculating the RFZ? Or do you have to think of them as "invisible" and calculate using the angle of the drywall behind? I'm assuming that standard soffits are constructed in such a way that they will reflect the frequencies needed for an RFZ...but I wasn't sure so I'm asking. (this applies to the left speaker reflecting off the right baffle and vice a verse)

-Is 5'5" too close for the direct signal hitting the ears? I think 6'5" is what I remember the recommendation being...

Alright that's it for now...let me know if you see any major problems or if you see a better way of doing the CR. I've gone through many options. I've also been trying to reach Event about some specs on my monitors but have had zero luck....arghh!! It's been a solid 4 days now. Hopefully I'll find out soon.

Thanks in advance!
Trevor

Hi Shybird,

Been following along on your design. As you well understand how important the designing stage is !

If I may ... this is something that brings up a concern

It has to do with the walls in the bathroom area.

It's difficult to clearly see what the structural layout is in that area of the design [from the posted floor plan], but the 'concern' has to do with how the bath area is being framed off, AND, more importantly, how the isolation walls are being displayed.

It appears as if there is only a single stud wall separating the bath from the backside of the control room, and the same issue into the main room ?!?

I would be very interested in reading what the 'experts' have to say on this.

Just trying to lend a 'critical' eye if it helps !!!

Hi RJ...once again thank you for the comments.

Sorry it's tough to see the walls in the image there...but I have drawn in a resilient channel that will help the bathroom remain as part of the outer shell (decoupled from the live room and control room). Stuart addressed this with me earlier in the thread. I am trying to save money on the bathroom and mechanical room and don't plan to do a complete "room within room" construction in those places. I am aware that the isolation will not be nearly what it is between other rooms. I'm ok with this at this point. If for some reason there is room left in the budget (highly doubtful) we might shoot for more isolation.

Cheers
Trevor

Here's two more with slight modifications. I think I'm liking Layout 14.1 the most so far. It has great sight lines between all rooms and has just enough additional space in the CR to make it appear more comfortable.

What do you guys think? Any opinions on the designs? Any preferences between the three?

Thanks a ton!
Trevor

Any opinions out there?

With both of those, the rear sections of the side walls seem to be non-parallel (which is fine), but they seem to be angled the wrong way, making the room narrower at the back wall than in further forward (which is not so fine). The room should only get wider as you go back, or stay the same width. It should not get narrower.

The right side should be easy to fix: you have some space behind that wall. But the left side looks like you might need to angle the bathroom wall a bit, to match.

- Stuart -

Hey Stuart, I can fix this...however I'm a little unsure why the room cannot angle inward like that past the mix position...it doesn't effect the reflections for RFZ in a negative way (unless I'm missing something) so I did it to allow the bathroom wall to be straight. Does it have to do with modal distribution? Or clarity of sound at the couch position? I'm really stumped on this one...

Thanks again for the input Stuart...I want to get this 2D finalized as soon as possible. We are moving forward on the tree removal soon as well as adding a huge gate to the fence for construction access and future studio access.

cheers
Trevor