Toronto One Bloor East | 257.24m | 76s | Great Gulf | Hariri Pontarini

Compare the shot above of 1 Bloor's core to the core of Aura below, taken in Sept 2010.



auras29bb.jpg
 
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doug said:
....except when the units are only seperated by drywall, which is common these days.
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I seriously doubt it is separated by only drywall. It is usually a double stud wall with special sound absorbing insultation
in between. Insultation absorbs sound much better than a hard surface. The bass sound from rap music which because
of the broad sound wave travels easily through a hard surface is a particular problem.
 
The biggest determinant with regards to reinforced concrete vs steel is that most construction companies in Toronto are set up for reinforced concrete, whereas in a place such as New York, the industry is primarily built around steel. You can do steel here for large structures, but it will cost you a significant amount more to do so. Both materials have their advantages and disadvantages.
 
Homer said:
I seriously doubt it is separated by only drywall. It is usually a double stud wall with special sound absorbing insultation
in between. Insultation absorbs sound much better than a hard surface. The bass sound from rap music which because
of the broad sound wave travels easily through a hard surface is a particular problem.
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What about transmission of high frequency sound waves for drywall?
 
dt_toronto_geek said:
What about transmission of high frequency sound waves for drywall?
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High Frequency sound waves do not travel through anything well, so drywall is generally effective in stopping the higher frequency sounds. When movie theatres only had speakers behind the screen, the movie sound was often over-balanced in the higher frequencies, to offset the loss of high frequency sound through screen. Also, the higher frequency sounds contain much less energy than base sounds - which is why the sub-woofers often have their own independent power supply - do no get their power from the amplifier used for other speakers.
 
Thanks AHK.
As an aside, movie screens have hundreds of thousands of perforations in them for sound to travel through. Since the 1960's premiere cinemas in large cities had five full range speakers behind the screen for 70MM 6-track sound (5 channels behind the screen, 1 channel for surround speakers placed around the walls of the room), all other cinemas only had one speaker for mono sound. Today most modern cinemas generally have 3 full range speakers behind the screen (left, right and centre sound channels) and anywhere from one to ten subwoofers back there for the bass channel, depending on the size of the room or the recommendation from the sound engineer. All speakers behind the screen are independently powered, sections of surround speakers can be powered by one amplifier. Back to sound through walls, for several decades it wasn't uncommon to be in a quiet scene during a film and hear sound coming from the cinema next door, presumably because of poor construction of the walls separating the cinemas. Today the problem I notice is just bass traveling through walls so while construction and soundproofing is better, sound pressure levels on film soundtracks are extraordinary.
 
The biggest determinant with regards to reinforced concrete vs steel is that most construction companies in Toronto are set up for reinforced concrete, whereas in a place such as New York, the industry is primarily built around steel. You can do steel here for large structures, but it will cost you a significant amount more to do so. Both materials have their advantages and disadvantages.
Click to expand...

The situation is similar in New York where office towers are steel while residential are reinforced concrete.
 
Homer said:
I seriously doubt it is separated by only drywall. It is usually a double stud wall with special sound absorbing insultation
in between. Insultation absorbs sound much better than a hard surface. The bass sound from rap music which because
of the broad sound wave travels easily through a hard surface is a particular problem.
Click to expand...

You may doubt all you want. I've lived in two condos twhere the units were seperated by single stud walls and type X drywall.

A massive concrete wall will stop more bass then a flexible sheetrock wall.

Broad sound waves...?
 
Forgive me if it's too off topic, it's just that the building code is sitting on the shelf behind me. If it's a newer construction doug they are required to provide a Sound Transmission Class Rating of 50. 2 Sheets of X drywall on wood studs is only 36. You can get a 50 rating if you hang the drywall on resilient channel (metal horizontal strips) and maybe fill the cavity with a sound insulation .

If we investigate further we would find that a 7.5" concrete block wall only has a rating of 50. A 5" thick solid concrete wall only has a rating of 52. Metal studs are better at absorbing sound than wood.
 
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