The HiFi Myth and Professional System Design

binbag

Rob, you lost me at hello; Adam Rayner does a much better job of selling your products than you do. (The latest HCC.)

Your cheesy intro would have looked awkward in a Russ Andrews pamphlet and you've spent most of your subsequent posts telling us what you never said.  If your product is as good as it seems you should go with quiet confidence rather than faith-healing evangelism. "Throw the crutches away Timmy!" doesn't work round here as most of us have figured out how to get along fine with them.  I'd save that approach for the necessarily cavernous pocketed novice that you can blind with science.

ryart

In view of the antagonistic (justified or not) and sarcastic tone of a few of the contributions I reckon Rob has been remarkably easy going in his replies. Just in case the cynical among you are wondering, I have never met Rob and didn't even know he existed before seeing this thread!

Having dipped my toe into the business of room correction at the lower frequencies I would be very interested to hear Rob's system and how the higher frequencies are handled. In my view you actually have to listen to audio products of any type before being able to make comparative comments on them, and even then temper any recommendations "with try lots of other things as your taste may be different". My aim is to enjoy the music and forget about the hifi; any tool which helps achieve that is worth considering. I do sympathise with those who can't consider much due to financial constraints. When I think back to my first stereo set-up when I was a student it didn't even have matching speakers. I still enjoyed the music though - perhaps we become more critical/obsessive as we get older or maybe it's because we can afford to be.

When it comes to explaining the science behind room correction methods I think it entirely reasonable to post links and let people read in as great or small a depth as they like. I can't see any point in trying to challenge Rob for the sake of it.

Interesting and worthwhile points from Blue Wizard and Mark in this thread. I agree with Mark's point about valve amps. IME they are rather curious in that accuracy seems to go out of the window but somehow the music sounds more like music. Also set up your system and room well for listening by yourself and it invariably sounds comparatively poor when friends come round for a listen. "Scientific" techniques and methods are a very useful tool but not a substitute for careful listening as well.

I seem to remember the Audyssey system received a favourable review from Phil Hinton when reviewed for this forum. Might be worth another look?

p.s. Enjoy the music however it sounds .

Rob Sinden

Dear Ryart

Thanks. Checks in the post and all that.

The bottom line is although I do make my living selling audio equipment I'm just as much an enthusiast as anyone else out there. Doing this for a living has taught me that simply buying good kit wont provide sound and that was my main point.

I'm also certain that now computers and computing are cheap the huge amount of number crunching involved to accurately measure and correct audio systems will gradually become common place - whaever flavour of speaker or amp you use.

Finally I'm trying to get people to have a listen to a good system and judge for themselves. Most retailers are terririfed of this technology which is probably what has pushed me so hard to point out the errors that rooms create.

Anyone care for a listen?

phil t

The rooms have always produced (in your words) errors, acoustics isn’t a new science.  What is it that pushes you so hard, the technology, that retailers don’t like the technology, or that you sell it?

Rob Sinden

A mix of all of this. The fact that many shops have good kit that they simply won't put in some of their dem rooms because they sound so poor.

The fact that that so few dealers are aware of how big an affect that acoustics have and therefore make no efforts to learn about it and how to negate it's affects.

If I could make a great sound consistantly in any room I certainly wouldnt be spending so much time on this crusade - I'd just be selling kit to people.

As you say the impact of acoustics isnt new - why then do most dealers know so little about their affects? Isn't it something that anyone involved in selling and installing systems should have a good working knowledge of?

BlueWizard

Well, a graphic equalizers, if used as it is meant to be used, can be very valuable, but it won't fix a broken room.

The problem is, that is not how most people use them, to most people a graphic equalizer is a really cool looking really complex volume control. It is not about balancing sound, it is about how many ways can I 'turn it up'; boost the bass, increase the overall loudness.

Now I don't really have a problem with that. It is your toy and if you are enjoying playing with it, then fine. But, a glorified volume control is not the true purpose of a equalizer.

I used to work in the AV shop at the university, mostly repairing audio equipment and movie projectors. My boss went to an audio seminar where a speaker (a guy not a woofer) demonstrated the correct method of equalizing a room, and keep in mind they were in a typical auditorium. He tested and tweaked this frequency and that until the graph of room response was absolutely flat.

Then just to prove how pointless the whole exercise was, he turned one of the speaker ever so slightly to the side, and it completely blew the flat response apart. The once flat graph was now a total mess.

So, if you equalize you room, as I've said, to absolutely flat, then invite a few friends over to enjoy your 'flat' system, the equalization is completely blown because of the addition of more people, more reflecting points, more absorbing points, etc... in the room.

But lets ask, what is the purpose of flat response. The room the original music was made in, especially if live, was not flat. The purpose of a flat, as flat as possible, response it to make sure you are not adding to or subtracting from the final product that the artist released.

But I'm not sure if I subscribe to this completely. I don't want to alter the music to the point of distorting the music or the artist original concept. But I have this audio equipment for my listening pleasure. If I want a touch more bass then I add a touch more bass. I would never buy a high end integrated amp that didn't have tone controls. As much as I want the music to sound right, I also want it to please me, and if pleasing me is slightly less than right, I'm OK with that.

Mostly I've been fortunate enough to have rooms with tolerable acoustic. Never great, but never horrendous either. Just common rooms, usually with carpet or rugs, curtains on the windows, and soft furniture.

But when you start trying to perfect a room, much like trying to electronically equalize a room, you start realizing just how complex the process is. Just as with the equalizer, if you acoustically correct an empty room, the correction completely changes when you invite a gang of friends over for a listen, and for the same reasons that it throws the electronic equalization off.

Keep in mind that acoustic perfection is so subtle that if you switch from a  fabric sofa to a leather sofa, you can completely throw your room off acoustically. Little things make big differences.

I dabble a bit in DIY speaker building and frequent those forums. There are many who believe it is wrong to design a speaker to be generally flat. They feel the speaker should be place in the room in which it will be used, and then tweaked and modified until the speaker and the room are in tune. If your building your own, that may have some limited merit, but if you are a manufacturer, you can't possible do that unless you as selling massively expensive speakers.

Keep in mind that some of the absolute premium many-thousand pound speaker makers will do just that. When you buy a speaker, and engineer delivers them to your home, and does his best to match the speaker to the acoustics of the room. Of course, if you put the speakers in a bad room, there is a limit to how much magic he can work.

For Joe Average, or more likely slightly above average, who intends to dedicate a room to his audio/video system. The key things I point out are, to make sure the back wall is not acoustically reflective. That is a good location for a combined absorber and diffuser. Behind the speakers, a similar absorber diffuser might also be in order. The floors should have a rug or carpet in front of the speakers. The walls should be soft and diffused. In this case, I would recommend a combination of fabric walls (flame retardant) and perhaps some diffusion/absorption boxes disguised a movie poster frames.

As to the ceiling, that gets more difficult. At worst, at least put acoustical tile on the ceiling. To go one step above that, put some type of diffuser on the ceiling to break up reflections.

Keep in mind that standing wave can just as easily form between the floor and ceiling as between the walls. We had one person posting here who couldn't understand why when he stood up his stereo sounded perfect, but when he sat down in his favorite chair, it sounded terrible. Likely he was moving into and out of nodes caused by floor to ceiling reflections.

These things sound complex, and certainly if you have the money, it is best left to a professional. But for those on a budget, some foam, some fiberglass or poly batting, some cloth from the fabric store, a few wood frames to hold it together, and it can be done for a reasonable cost.

For those on a super low budget, just hanging some cheap curtains or a low cost printed tapestry on the walls, especially the back wall, can act both as absorber and diffusers. It is not ideal, but it is better than nothing.

So again, most here agree with the basic concept that a bad room equals bad sound no matter how expensive the equipment.

But to simply say search it on Google doesn't do much to establish your credibility in the matter. If you are an expert, then you must have expert advise to give. And if you are not willing to give that advise freely, then how can we trust that you have the knowledge and expertise to be trusted with our home audio projects?

I'm not suggesting you cover every detail in this threat. But you referenced your blog, which I found about as substantial as your posts here. That might be the place to lay out the basics. What is happening and why that affects a listener? What can you do, in principle, about these various problems?

As things go, I've probably established myself as more of an expert than you have, and I can assure you I am not an expert. Just a person with high needs and low cash, who as a results, has had to learn self-reliance in all areas of life, from car repair to speaker building.

Just a few random rambling thoughts.

Steve/bluewizard

supahyp

Thank you Rob ,  for an excellent , informative posting .
I found some of the replies by others here difficult to understand . Are they saying that what you said in your intial posting was wrong , or do they object to you posting the info because you have a vested interest ?
Either way you have given me at least invaluable tips on how best to get accurate sound , and for the record as naive and gulliable as I may be , at no point did I feel you were giving any kind of sales pitch for your products .

Rob Sinden

I've never said I was an expert - just that I'd had some training by some.

I've never said I was trying to get flat response.

Saying that changing one thing in a room makes doing any room correction not worth doing seems ridiculous. Does room correction have to be 100% correct or not worth doing at all?

My aim was to point out how much rooms change audio systems and to give some suggested ways of reducing this problem.

phil t

I guess the initial post that you saw was different to the one I saw, because at no point have I seen any "invaluable tips".

For the record, I have only been following "The HiFi Myth" posts.

craigd

I own a Lyngdorf 2 2 system that was sold to me by Rob Sinden.

Having been a forum member for a couple of years now I recognise why Rob has been met with some hostility. I have decided to post in this thread as I may be able to answer questions in what is perceived to be a less biased manner.

Over the past 3 years I have spent a significant amount of time researching room acoustics, tweaking the various systems I have owned and experimenting with room correction in different guises.

For your perusal, I have attached a frequency response curve of my current system generated using REW and the calibrated microphone that is supplied with the Lyngdorf TDAI-2200 with RoomPerfect. 'Bypass' is the frequency response without room correction engaged, 'Focus 1' is the optimum correction setting for the main listening position and 'Global' is the frequecny response and the listening position, but is purported to sound better all around the room too.

I am pleased with my purchase, but also recognise it limitations. It is my opinion that in my (terrible) room and to my ears, regardless of budget, no hifi system that does not employ room correction could sound better.

So, are there any (serious) questions?