Soundproofing and Acoustics

Home Theatre or Surround Sound

noreply@blogger.com (Ultrafonic) — Tue, 15 Jan 2008 23:27:00 +0000

Here goes another post that could be misconstrued as complaining, but it's not. My point is to help set reasonable expectations for those spending time and money on this very popular entertainment. One reason for even thinking of doing this is the number of calls we get from people who have gone down the home theatre path, only to have all sorts of problems with the sound. It is always harder and more expensive to rectify after the fact and often impossible to make the system live up to the original expectation. My job isn't being a psychologist trying to reset peoples expectations and make them happy but that's what I end up doing. In effect I am cleaning up after sales people who mislead, either consciously or not, to get a sale. A bit of honesty and education on their part would go a long way to making happier customers who will more likely be return customers. Not to mention the simple human decency of being honest.

The first thing to remember is how the sound for home theatre is made. It is done in an acoustically treated room with speakers set up like this.

They are full range speakers and the sub is not used as such. All the bass comes from the 5 identical speakers. The sub is called LFE and is only used to add extra emphasis to Low Frequency Effects.

Every departure from this setup is a departure from how it is meant to sound. Of course very few people can have such a dedicated setup and so compromises are reasonable to expect. The average home theatre is so far from this setup though, that it has slim chance of creating the intended sound. In fact it becomes more "surround sound" than home theatre - hence the title of this post. In other words there will be plenty of sound everywhere and some level of effects. It won't however be the intended experience. This of course is fine and most people will be happy with it. It is certainly an improvement over just a TV.

It's not only the quality of overall sound effects that we get calls about though. Common complaints are that the bass is uneven around the room and boomy in places, dialogue and loud effects are so vastly different in level that constant volume adjustments are made, and listening at anything above moderate levels becomes tiring quickly. These kinds of problems are not experienced in a correctly setup and acoustically treated room.

Acoustics for Hi Fi and Home Theatre

noreply@blogger.com (Ultrafonic) — Mon, 07 Jan 2008 23:40:00 +0000

In the modern home there seems to be a minimalist design trend at the moment. It uses tiles and wood floors, long flat rectangular walls and ceilings and lots of glass. Quite the opposite of some years ago where everything was upholstered, carpeted and curtained. They also have a lot of open plan design with lounge, family room, dining room and kitchen often running into each other.
These type of rooms have no chance at all of being good for listening to stereo or home theatre. They are an acoustic nightmare and it doesnt matter what equipment you use, it will not reproduce the program as intended by the recording engineer/artist. To get some idea of why, consider the environment it was engineered in and what a good listening room is like. First and foremost, since we have 2 ears, one each side of our head, the room MUST be symmetrical. It can't have reflections or reverberation that is sufficient to interfere with the sound from the speakers and it cant have direct reflections in the immediate area - like hard walls and ceiling. The size of most listening rooms is similar to the length of bass frequencies which means physical effects like standing waves will occur. Some form of control commonly known as bass traps must be used as this effect can not be corrected electronically.

Ultimately, if you are striving for a genuine reproduction of what was recorded you need a dedicated room!
So what's the point of this rant? It doesn't mean that unless you have a dedicated room you shouldn't have a HiFi or a home theatre, but you should set your expectations properly and perhaps not spend money on relatively very expensive marginal improvements like some of the crazy cables available. It means that if you have a room that is not ideal, don't go crazy on acoustic treatment either. Just get whatever soft furnishings, rugs etc that you can in there. Perhaps use some acoustic treatment that can also be decorative like the Fonic Acoustics Designer Panels. Don't spend time, money and effort trying to make such a room sound perfect because you won't be able to. Don't pay people to advise, measure or sell you anything other than the basics. Have the right expectation that it will sound OK or possibly even good but not sensational or anything like the real thing.

I write this because I get so many calls from people who have bought very expensive gear and put in a beautiful modern home and it doesn't sound good at all. They ask me to consult and fix it which as I said is almost impossible. My point is that this would be a lot more acceptable if their expectation was reasonable at the outset. HiFi and home theatre sales people should be able to make this clear to their customers at the time of sale. They may not get quite such a big sale but will have customers who aren't dissapointed when they get home and are much more likely to be return customers.
Some more information can be found in the articles here - http://www.ultrafonic.com.au/Articles.htm

Practical Soundproofing and Acoustics

noreply@blogger.com (Ultrafonic) — Sun, 23 Dec 2007 23:58:00 +0000

I have created this blog in an attempt to cut through some of the confusing information out there regarding soundproofing and acoustics. Most of it simply frustrates and saddens me because it causes people to spend time and money on things that should generally bring joy but more commonly bring disappointment.

I'm going to be as blunt and provocative as I can and do it quite openly. It's not an attempt to annoy anyone but rather to draw out what is real and what is not. More so it is meant to get to what is appropriate and cost effective. My analogy is that anyone can build a bridge over the river that is perfectly safe and will never wear out with a very smooth ride - just fill the river with millions of tons of concrete and put huge pipes under it! This however is far from good engineering, which to me is getting the best possible result within a budget and making it appropriate for the owner/user/customer.

I'll make a start soon but if anyone has specific ideas or questions, I'll do my best to answer them.
In the meantime you may find some useful stuff at www.ultrafonic.com.au or www.fonic.com