5.1 Control Room

Hi everyone. I'm a tech a small further education college in the UK. We have a been giving a bit of money to move some rooms in our dept but not enough to pay someone sadly so it has fallen on myself to do the designing! I have been a spectator on here for a while and have dabbled in the odd bit of design before using this site as a reference. We would like the space to look great as well as being acoustically sound, no pun intended! I have designed a control using the EBU 5.1 template on Sketchup. I would like to soffit all the 5 adams A7s. I really love the look of Helmholtz slotz resonators though I haven't managed to get my head around the calculator yet! We have a budget between £3000-£5000 to do the construction work in this room. Isolation is really an issue with this room though I was thinking of putting soundbloc on the existing walls. They're all solid walls i think made out of breeze block then plastered. it has a false ceiling at 9' and goes up another few feet though there's pipes that they're hiding that would be best kept hidden. The questions i have about my design; 1: would it work? 2. should i carry on the resonators to the back doors or should i opted for a different treatment? 3. I like the idea of having a raised section behind the listening area so students can see whats going on a bit easier, i would there be any negative effects to this or a better way of doing this? 4. Is there an optimum frequency i should be tuning the resonators for? 5. I've seen a few post about using board band absorption above speakers though this has a mixed consensus , should i be looking at doing this? Thank you for looking at my collection of brain farts. I look forward to hearing your thoughts! Many thanks Jimi

Hey guys. Just wondering if I left something out of my post that I should've included? I understand everyone's busy and that it takes time to get back to everyone but I just want to make sure I complied with all t&cs Thanks James

Hi there Jimi! Welcome to the forum! :) Sorry you ended up waiting do long for a response: I've been real busy the last few weeks on a project, and unable to check the forum, and it looks like nobody else is helping out with answers either, right now! Anyway:

I really love the look of Helmholtz slotz resonators though I haven't managed to get my head around the calculator yet!

You can probably just use John's generic dimensions for your slot walls. They should work for most rooms, to get you some general broadband treatment.

I was thinking of putting soundbloc on the existing walls. They're all solid walls i think made out of breeze block then plastered

Do you have photos of those walls? It always helps to actually see what you are dealing with...

1: would it work?

The basic plan looks OK, but the rear soffits probably don't need to be as big as that. In fact, some people just use stands for their rear surround speakers. In your case, if you are going to have people sitting at the back, those soffits would block the view for them. Also, with people sitting behind the rear surrounds, they won't be able to hear the 5.1 effect. You might need to have a duplicate set of speakers right at the back, that can be turned off for critical work in the CR, or turned on when there are people listening in the rear section.

3. I like the idea of having a raised section behind the listening area so students can see whats going on a bit easier, i would there be any negative effects to this or a better way of doing this?

That's fine. Many studios have a raised section at the back.- As long as you build it right (No resonant cavity underneath!), you should be fine.

4. Is there an optimum frequency i should be tuning the resonators for?

Not really: the slot wall is more of a broadband device. You can tune individual slots if you want, but that's usually not necessary, unless you have something really problematic that needs special attention.

5. I've seen a few post about using board band absorption above speakers though this has a mixed consensus , should i be looking at doing this?

Which speakers? A 5.1 room is rather complex to design, since you have reflective surfaces all around, and speakers facing them. It's different from just a 2.0 or 2.1 design. - Stuart -

Hi Stuart, thank you for your reply, it's much appreciated. I've had a look around the forum and I'm struggling to find John's generic dimensions for the slot walls. Are you able to point me in the right direction please? i will In regards to the rear soffits, i used the EBU calculator on sketch up so the angles were correct. If I made the soffits smaller wouldn't that mess up the angles? Would you fill the cavity with rockwool? 5. The absorption I was talking about was above the speakers on the soffits. I've seen on the forum that some have suggested to put board band absorption above to tame reflections. just wondering how thick the absorption i would need if i needed it at all? Also On point 2. do you think it would be a good idea to carry on the slot resonators all the way down the walls? Thank you again for your help Jimi