The HiFi Myth and Professional System Design

MilkyJoe

Just get it over with and tell us what the product entails, and exactly what it costs, without using phrases like "room modes". Is it a carpet to hang on the wall? Explain it exactly and then we can decide.

Rob Sinden

I'm sorry I cant talk about acoustic problems without using terms like room modes. It would like talking about speed without mentioning mph.

Google Room Modes and you'll find masses of info. When you've learned how important they are, you understand what I'm talking about and see why every room will dramatically distort any audio system you put in it.

Try this as a starting point.

Acoustics Crash Course 1 - Modes

Mark.Yudkin

To be frank, yes, that is exactly the message that is coming across - that you are not building systems to enjoy music.

Now try rereading my post (#36) in the light of this insight. And remember, I agree with acoustically treating the room.

KJ Palmer

Can you change the 'room mode' to cater for different musicaal styles/tastes? Eg. listening to a Beethoven symphony in a large hall mode as opposed to a grunge band in a small gig venue mode.

Mark.Yudkin

A room mode can only be alteredy physically altering the positions of the walls, is it's caused by the interferences with the reflections of the sound waves at the room boundaries.

However, room modes are more of an issue at the lower frequencies, and less of an issue at the higher frequencies. This is why electronic correction for subs is essential (kills the peaks), whereas correction at higher frequencies is of lesser value, and can even be detrimental, especially if reflections and interactions aren't compensated (time dimension).

What you want is typically emulated by using DSPs and loudspeakers: using speakers instead of room reflections. My experience is that it doesn't really work well.

Rob Sinden

My communictaion skills really need a lot of work if it's not clear that buidling a system to enjoy music is what I'm trying to achieve. I doubt you'll find many people who have spent more time or money than me trying to achieve exactly that.

Perhaps the science that I'm trying to point out makes me at odds with what most of the rest of the industry. But science is a necessary part of reproducing sound which is what I'm discussing here.

Is it acceptable to invite members to talk on the phone as I'm not sure I understand what you are saying in your other reply?

You can add voicings on some of the systems we use but for now all I think that is important is reducing the negative affect of the room which is what I'd like to stay focused on.

Rob Sinden

Room modes are clearly much more of a problem at low frequencies but I was simply amazed at how much of a difference room correction makes to all the speakers in a surround set up and to the mid and hf performance of most stereos in most rooms.

One great benefits of most room correction systems is that you can toggle them on and off once they have been set up. This makes the benefits - or problems they create very easy to audition.

Please remember I have recently built a money no object listening room and I find big benefits using room correction even in this relatively "perfect" room.

MilkyJoe

If you've explained any science here then I'm a monkey's uncle. I did my degree in Neuroscience, and I knows science when I hears it. You also haven't divulged what I asked in my last post...

BlueWizard

"I ask again – please tell me how you get accurate sound quality without measuring and correcting a system? Do the laws of physics not apply in your rooms?"

No but the laws of Economic do apply.

Now to be fair, you are talking in the framework of people buying better and better systems, which in turn implies relatively expensive system. So, if you have a bundle of money tied up in a system, then expensive testing, equalization, and room corrections are in order, and are really necessary to get your money's worth out of the price of an very expensive system.

But that is only the top of the pyramid. Even if you are going to do it yourself, you still need a computer, some testing software, and a reference microphone as well as a pre-amp and a test jig; depending on the type of testing.

But most consumers can't afford this, and they certainly can't afford a professional to come in and do it. Though equally there are some people who can afford it and definitely should do it.

I'm not arguing with your basic premise, but again, you are lean on usable substance. There is a lot of information about why you need to consider room acoustics; reflected sound, standing waves, peaks and valley of sound, equalization, and many other aspects that are of benefit to anyone at any level to help them understand.

For instance, it does little good to electronically equalize a room, since the minute you invite a bunch of friends in, the acoustics change that the preset equalization is now way off. Also, equalization does nothing about standing waves. So, there is an electronic component that needs to be considered, and there is a room acoustic component that needs to be consider. Doing one without the other might be educational, but beyond that is something of a waste of time.

So, it is not that we are disagreeing with your basic premise, on that we all agree, and I think we all agree that it is something too many people ignore.

But, where do we go from there? What do we need to know to have a basic understanding of what and why this is happening?

Exactly what is a sound absorber, and what is it made of?

Exactly what is a sound diffuser, and how can it help?

How far do I have to take it? It is something of an impracticality to spend £5000 on room treatments, to make my £1000 audio system sound better. But you have a fair point, if instead of putting £5000 into room treatment, I put it into audio equipment instead, then put that audio equipment into the same bad room, it is going to be disappointing.

You need to offer solution to people on a budget as well as to people who can afford to spend a fortune.

What do I do if I have an average room with £1000 worth of equipment and another £200 to spend on making the room right? Got an answer for that?

What do I do if I have an average room and £500 in equipment and another £100 to spend improving the room?

Certainly if I've got £10,000 in equipment and another £3000 to spend, you might have some nice suggestions. But everyone has a problem with bad room acoustic, you simply can't limit your help exclusively to people with thousands to spend. And whether you intended that or not, that seems to be how you are projecting yourself.

But simply pointing out the problem isn't helping, though it is a good start to raise awareness of the problem. But awareness is nothing without solutions, and solutions have to come at all budgets. Poor people's rooms are just as bad as rich people's room, but it is much harder to solve the problems for poor people. Yet, the problem still needs to be solved.

So, again, no one is arguing with your basic premise. Most rooms suck, and good equipment in a bad room, is also going to suck. I suspect there is a point, where incrementally better equipment actually sounds worse if the room itself has not been proportionally improved. And that is probably the very point you were making, that improving your equipment without equally and proportionally improving your room, is sure to lead to disappointment. Again, I think we all get that.

But people don't need to hear that they have a problem. They need to know why they have a problem, and what they can do about it. And what they can do about it on their frequently limited budgets.

Yes, ideally we would all build perfect rooms and have them perfectly tuned, but what can I do between now and when I win the lottery? That's what we need to hear.

Not trying to put you down, just trying to get you to expand on your body of knowledge to help people understand the problem and the solutions.

Steve/bluewizard

Rob Sinden

Marvellous. As a man of science I'm sure you appreciate what standing waves are all about. I simply wasn't aware that the deviations they create to an audio system in most rooms are typically around 20db.

Me pointing this out was intended to get people looking into the subject and science of sound further. As I just said Google "room modes" or "standing waves" and you'll have a whole raft of individual experts that will explain the science.