slanting glass between control room and tracking room...

[jnobucks]

So, I've looked all around this forum and others for more info on this and I have found some very good info, but still a little unsure.
I am building a separation wall between my control and tracking rooms and will be ready in a few days to have my glass guy come over and take measurements. I can't decide whether to go with two straight panes of glass to give the most amount of space inbetween the panes, slant one pane (top in towards control) and keep the other pane straight, slant both panes the same direction or slant both panes ooposite directions.

I have read that slanting the windows for sound reflection is a myth, then other posts tell me that it really matters. I have read that its mostly for light reflection concerns, but you should just position your lighting accordingly. I have also read that whether it matters or not, it attracts more clients and gives the room a professional feel. As with most debated topics on Gearslutz, the more I read about it, the more confused I am on what I should do. Any help? Thanks in advance!

Brian.

[avare]

Originally Posted by jnobucks

I have read that slanting the windows for sound reflection is a myth,

Correct.

I have read that its mostly for light reflection concerns, but you should just position your lighting accordingly.

Correct.

Beyond that, angling reduces the space between the glass, which reduces the sound isolation of the window.

For more information read Myth Number Three in Exposing Acoustical Myths. You will probably find the rest of the article quite useful also.

Have a look at the rest of RBDG's of website for pictures of world class recording studios.

Transparently,
Andre

[jnobucks]

Thats great information Andre, thanks so much! Very informative link.

Anyone else?

[Stick]

Mine are on one of the splayed side wall of my control room, so I needed them to be straight so the reflections are the same on the left and right. Light reflections haven't been a problem for me.

Hard to see in the pics, but here's my studio.

[CKK]

Its all about light reflections, it has nothing to do with the sound.

With two sets of glas that is put up verticaly it will act as a mirror and you will see your reflection twice no matter how you put up you lights.

If clients pay more attention to the glas than the gear and the operators knowledge, they are not worth recording in the first place.

I have never had clients saying "ya ya, I dont care about your vintage gear and your track record - I WANT TO SEE YOUR WINDOWS". And if that will ever happen, I will show them the window - from outside my studio, I might even give them change for the bus.

[CKK]

Ohhh, and by the way. Some of the biggest studios have big slide doors made of glas to seperate the different live rooms. Try putting them in an angle.

[str1ke4ce]

Originally Posted by jnobucks

Thats great information Andre, thanks so much! Very informative link.

Anyone else?

I angled mine, just so noone would question why I didn't. and if you angle both sides of the glass, your space stays the same for the air isolation. Never heard of light thing before today, guess I wont have to worry bout glare

[jayfrigo]

Even though traditional control room window angles are useful mainly for light reflection, and allowing that reducing airspace will reduce isolation to a degree, don't take that to mean that you can ignore the reflection path from the glass.

It can be simply an un-angled window in an angled wall to direct the reflection where you want it, but there may be times when you indeed will angle the window itself for sound reflection. Of course, in most cases it's in a big wall that is going to be reflecting as well, so angling only the window doesn't do much, but every room is different, and glass certainly reflects, especially mids and highs, so don't ignore it. I've had design situations where it definitely made sense as part of the whole-room plan.

[jayfrigo]

Originally Posted by str1ke4ce

if you angle both sides of the glass, your space stays the same for the air isolation

But in most constructions, you've then utilized less airspace than you could have, had you simply used straight glass. 6" top and bottom on an angle isn't better than 9" top and 6" bottom. 9" top and bottom is better still.

Of course this is all just theoretical until you figure out how much space you actually have, considering all factors, even including simple convenience-of-use issues like light reflection, and perhaps run a couple numbers to predict TL and fit it into the design criteria.

Point is, if you still get the iso you need according to your design goals, it doesn't matter if you lose a bit of air-space to an angle. On the other hand, if the angle prevents you from attaining your goal, making the window a weak link in a in a strong chain of a high-TL wall and door (you could do a TLcomp calculation to predict just how weak), then you need a different solution.

[DeadPoet]

Originally Posted by CKK

Ohhh, and by the way. Some of the biggest studios have big slide doors made of glas to seperate the different live rooms. Try putting them in an angle.

....errrr... You're only thinking of vertical angling, there's also horizontal angling (which I've seen a lot btw)







Herwig

[kickdrummer58]

If the glass isn't angled this can create a resonating chamber. Light is also a good reason to angle but the way it was explained to me was SOUND. We do not build our walls parallel for the same reason.

[kickdrummer58]

Speaking of sliding doors being put in at an angle. There is a big studio here in Nashville with just that. The doors lean back with the wall. They don't slide well but it's been done.

[jhbrandt]

Originally Posted by kickdrummer58

If the glass isn't angled this can create a resonating chamber. Light is also a good reason to angle but the way it was explained to me was SOUND. We do not build our walls parallel for the same reason.

Whoever explained that to you was wrong. It is a myth. Any resonances within the 'chamber' are taken care of with the surrounding absorption material. Some people build nonparallel walls for that invalid reason also. Splaying the massive shell walls very often can cause modal issues.

Originally Posted by kickdrummer58

Speaking of sliding doors being put in at an angle. There is a big studio here in Nashville with just that. The doors lean back with the wall. They don't slide well but it's been done.

What studio? Why did they do that? and What is the difference with and without the slant? I doubt very seriously that the pros outweigh the cons.

Cheers,
John

[nosebleedaudio]

Originally Posted by kickdrummer58

Speaking of sliding doors being put in at an angle. There is a big studio here in Nashville with just that. The doors lean back with the wall. They don't slide well but it's been done.

No to nick pick but the door would have to slant a high amount to make a noticeable difference, say at least 15deg..

[kickdrummer58]

It's prety drastic IMO.

I really disagree with not slanting the glass. Have you ever hit a good size window like this that's sealed well. If not angled it does resonate. Think of it like a drum. I experienced a window with parallel panes that did resonate when struck. Maybe I'm crazy but If I was building one I would make sure the panes were not parallel. Actually had the chance to help build a studio and we did the windows between the booth like this with about 1.5' to 2' between and got no resonation.

I can see where it wouldn't be so easy to tell in a Shalow window but deep windows I think this is more prominant.

.