One of the local hi-end shops has a lot of great gear - McIntosh MC2K amps and speakers, B&W800d, Wilson Maxx 2 etc... I go there once in a while to listen and occasionally purchase. Was in there ordering the ARC for my Anthem D2 and the owner mentions to me that I should listen to the Lyngdorf system they have. Sure, why not.

It was hooked up to a pair of Revel Salon 2. I must say, I'm very impressed with certain aspects of the sound these speakers produce. If they had come out a couple of years ago I would've considered them (and saved some $$$ to boot!). Only problem with them is that imho they look a little "plasticky", but less so in person than in pictures.

The owner kept on raving about the Lyngdorf and we could A/B very quickly and easily. I don't know if it was setup wrong but overall I preferred the "natural" sound of the speakers over the Lyngdorf'd sound. It added midbass but far too much nasality to vocals. Anyone else hear the Lyngdorf, and what did you think?

The Bogg, thanks for the report. I intend to audition the Lyngdorf in a few weeks myself.

I have seen Lyngdorf as well as TacT and much prefer the latter as it lets you do more on your own whereas the Lyngdorf is a set it and forget it unit

It was hooked up to a pair of Revel Salon 2.

Can they only do room correction for 2CH?

Yep

I thought Lyngdorf only did 2 channel & bass?

Where are you going Michael? I thought I saw that Austin had a dealer.

Doesn't Lyngdorf have a connection to TACT?

I don't think people should be trying to monkey with upper frequencies. IME with DEQX, I found that EQing a passive speaker to be more accurate had more downsides than upsides. It was only when you bypassed the passive crossover than the sound improved and dramatically so. IME with Audyssey, the stock curves made the speakers sound unnatural as well in the upper mids and treble. The NAD curve is much more natural sounding, but isn't *always* better than bypass, ESPECIALLY with a good speaker, sometimes it is just different. NAD's Audyssey is great for a bad sounding speaker or bad sounding room. As far as bass, Revel Ultimas have incredibly accurate bass. What you're describing almost sounds like a 'boom and sizzle' approach.

Having sold the original room correction system for 10 years (SigTech --- may they rest in peace), it is not a problem to correct the high frequencies if done correctly. We had the ability to reduce the amount of correction applied as you moved up the frequency spectrum. Big narrow dips should not be corrected (alway audible) and if you correct with too much precision in the higher frequencies, you end up with the "head in the vice" problem. Meaning it sounds great if your head doesn't move but if you move just a tad, everything goes south. With the Tact, you only partially accomplish that a different way (by adjusting the target curve).

In my experience, the completely automated correction of a speaker (sub included) is almost always wrong.

Tried it with a pair of B&W 802D and I was not impressed.

Tried it with a pair of B&W 802D and I was not impressed.

Then it was done improperly !

Then it was done improperly !


Or it was done proper. There are big problems with room correction.

Wow, well that settles it. I mean, problems like what, not counting the ones that audioguy already mentioned above?

Wow, well that settles it. I mean, problems like what, not counting the ones that audioguy already mentioned above?


The biggest problem is that out ears and the microphone are not hearing the same sound.

that is right. the mic hears substantially more.

Besides, granting for a moment that that's a complete argument, it's an argument against overcorrection, but not all correction.

that is right. the mic hears substantially more.


It hear wrong things, yes. The human ear hear different if the sound comes behind it or in front of you, the mic do not do that. You also hear different because of your shoulder will effect the sound and the shape of your ear. Many other things that make "perfect" room correction probably impossible and fixing the room a better choice.

The mic and room correction often try to correct things in a way that makes things subjectively worse.

The human ear hear different if the sound comes behind it or in front of you, the mic do not do that.Depends on the mic. Not all mics are omni.

But who says you're relying solely on the mic? Of course you're not going to do that. You can listen and measure, too.

The bottom line is that it's a logical contradiction to say, as you did, that "proper" room correction can make things worse. If it sounds worse, you didn't do it right. It could be that for some rooms, some speakers, etc., "doing it right" means doing none at all. But that's not universally the case.

I think he meant that you can follow the procedures properly and still end up with a worse result. Audyssey can be like that.

I think he meant that you can follow the procedures properly and still end up with a worse result. Audyssey can be like that.

That's because knowledge and common sense are also required. Of the hundreds of systems I installed, very, very few would sound correct if you "only followed the instructions". Which translates to what I said earlier....which was that it almost never sounds optimal if you allow the system to do all of the work. That is true for Audessy, Tact, The SigTech and the Velodyne SMS system. Humans (most) have reasoning power that most automated systems do not. Some of the computer-based chess systems get close but that is only after bazillions of manhours and many decades of work by lots of very smart people. That level of effort has not been invested in ANY room correction system.

I think OB has some buddy that apparently is OCD about his Tact system and according to OB, his system sounds great. If one is both willing and able to invest the time to really understand how these systems work and then apply that knowledge to the implementation, the results are almost always amazing.

That's because knowledge and common sense are also required. Of the hundreds of systems I installed, very, very few would sound correct if you "only followed the instructions". Which translates to what I said earlier....which was that it almost never sounds optimal if you allow the system to do all of the work. That is true for Audessy, Tact, The SigTech and the Velodyne SMS system. Humans (most) have reasoning power that most automated systems do not. Some of the computer-based chess systems get close but that is only after bazillions of manhours and many decades of work by lots of very smart people. That level of effort has not been invested in ANY room correction system.

I think OB has some buddy that apparently is OCD about his Tact system and according to OB, his system sounds great. If one is both willing and able to invest the time to really understand how these systems work and then apply that knowledge to the implementation, the results are almost always amazing.

One of my best friends indeed has a TacT equalized room that I'd probably the finest room I have ever heard. He got involved 2-3 years ago and has made it a 2 hour per night obsession. He explained to me that most people install the unit use the mics then set it and forget it. He said this perhaps does 10% of what the unit is capable. He showed me all of the algorithms you can start with but that is just the beginning. He will then go in and smooth out by fractions of a DB certain frequencies. He will do this for hours each night. When I heard his system I want prepared for how great it sounded all because of his TacT. He has also changed caps on the unit as well as a different power supply. Simply put if one spends the time getting into the unit and doing some work the results are mind boggling.

It hear wrong things, yes. The human ear hear different if the sound comes behind it or in front of you, the mic do not do that. You also hear different because of your shoulder will effect the sound and the shape of your ear. That's a red herring argument and wrong. In order for your particular HRTF to remain effective, the impinging sound should not include a correction for it! (If there was such a correction, one would need headphones to appreciate it.) What is needed (and approximated) is an entirely unbiased measurement, independent of the particular listener.

That's a red herring argument and wrong. In order for your particular HRTF to remain effective, the impinging sound should not include a correction for it! (If there was such a correction, one would need headphones to appreciate it.) What is needed (and approximated) is an entirely unbiased measurement, independent of the particular listener.


No, it is not wrong. There is a reason why people STILL fix the rooms and not using room processors. With the processor you CANNOT do different things in the room like with room treatment. You cannot have some surfaces that are damping and some other surfaces that should reflect the sounde with a processor, like you can with room treatment. The processor only hear the total sum of the room, it cannot know how much the floor is reflecting, or the left wall.

Plus you will have the problesm that the sound is different in the room. But if it make you happy, be my guest.

The mic and room correction often try to correct things in a way that makes things subjectively worse.


The problem is many, like I said. Different sound in different parts of the room, that fact that the mic and processor only listen to the total sum of the room, the fact that you cannot make different treatment in the room, etc.

But hey, some people like those processors and maybe they cannot fix the room with regular treatment, then it maybe can be better than a untreated room.

That's a red herring argument and wrong. In order for your particular HRTF to remain effective, the impinging sound should not include a correction for it! (If there was such a correction, one would need headphones to appreciate it.) What is needed (and approximated) is an entirely unbiased measurement, independent of the particular listener.

C'mon Kal Nin74 is never wrong.

Kal is it fair to say therefore that the mics used in TacT and Lyngdorf etc is what you are alluding to?
I never thougt I would be a believer in digital room equalization until I heard my friend's system and having him explain to me what the TacT is capable of.

C'mon Kal Nin74 is never wrong.


Of course I'm wrong sometimes. But I don't believe all crap that hifi magazines and dealers tell us. I believe in the scientific way of hifi, not the voodoo side. :)

No, it is not wrong. There is a reason why people STILL fix the rooms and not using room processors. With the processor you CANNOT do different things in the room like with room treatment. You cannot have some surfaces that are damping and some other surfaces that should reflect the sounde with a processor, like you can with room treatment. The processor only hear the total sum of the room, it cannot know how much the floor is reflecting, or the left wall.

Plus you will have the problesm that the sound is different in the room. But if it make you happy, be my guest.Irrelevant. What I was addressing was your comment about the inadequacy of microphone measurements due to their lack of attention to HRTF matters as a reason why the measurements/compensation is wrong. That argument is bogus and has nothing to do with the differences between physical acoustical treatment and electronic EQ.

I fully agree with you about the superiority of acoustical treatment over electronic EQ but it is not due to the any failure to acknowledge HRTF.

Of course I'm wrong sometimes. But I don't believe all crap that hifi magazines and dealers tell us. I believe in the scientific way of hifi, not the voodoo side. :)


well you need to learn a bit about digtal room correction and mics because you don't have any idea

Of course I'm wrong sometimes. But I don't believe all crap that hifi magazines and dealers tell us. I believe in the scientific way of hifi, not the voodoo side. But NIN74, that's why I'm surprised you're on the wrong side of this room correction argument. I think you'd be quite enthusiastic about its potential and far more constructive about its pitfalls. Of course it's not perfect! But nor is simple equalization, and that can be quite helpful sometimes too. Room correction is simply a more flexible and powerful superset of equalization, which also makes it more dangerous if used improperly.

Kal is it fair to say therefore that the mics used in TacT and Lyngdorf etc is what you are alluding to?
I never thougt I would be a believer in digital room equalization until I heard my friend's system and having him explain to me what the TacT is capable of.I was speaking generally but, I guess, I would include those systems. Mind you, I was not disputing his tirade about the superiority, in many ways, of acoustical design and treatment. I was merely disputing his specific argument about measurement.

Of course I'm wrong sometimes. But I don't believe all crap that hifi magazines and dealers tell us. I believe in the scientific way of hifi, not the voodoo side. :)

Then read the AES paper for the Lyngdorf Room Correction system. The tool is based on science. The basic is that the system measures multiple points within the room to get an estimate of the power response of the room. Then for the specified sweet seat, it makes corrections which are bound by that power response. So if the correction for an individual frequency exceeds those bounds it will not correct beyond that point. In the end, their goal is not to modify the sound of a particular loudspeaker; but rather it is to minimize the effect of the room on that loudspeaker. Whether or not you like the sonic result of the technique is another question altogether, and a highly subjective one at that.

I do agree that if you don't start with the room, you've got an uphill battle. Any of these tools should have far less "work" to do in that case. However, improving the sonics of a bad room isn't a bad thing for those that haven't gone that route.

Cheers,

That's because knowledge and common sense are also required. Of the hundreds of systems I installed, very, very few would sound correct if you "only followed the instructions". Which translates to what I said earlier....which was that it almost never sounds optimal if you allow the system to do all of the work. That is true for Audessy, Tact, The SigTech and the Velodyne SMS system. Humans (most) have reasoning power that most automated systems do not. Some of the computer-based chess systems get close but that is only after bazillions of manhours and many decades of work by lots of very smart people. That level of effort has not been invested in ANY room correction system.

That's why I've challenged Audyssey to allow more installer input. I call it the 'trained monkey' system. Why should the system be trying to do the braille method on the room/setup if the installer can simply input some of these things? I have to tweak every Audyssey setup I do as it is close, but never right. The good thing is that this stuff gets better and better, smarter and smarter every year. And at least it's not like throwing away money on baseless tweaks.

Does lyngdorf have their own room correction or is it based off of something else?

Does lyngdorf have their own room correction or is it based off of something else?

It's their own: www.roomperfect.com (remember that Tact USA and Lyngdorf once used to be the very same company only until Radomir Bozovic and Peter Lyngdorf decided to part ways about 2 years ago).

Peter

"The processor only hear the total sum of the room, it cannot know how much the floor is reflecting, or the left wall. "

Not so.

1) A single mike can distinguish between direct and reflected sounds by when they arrive.

IMO this makes it overgeneralizing to call EQ room correction, as this makes it straightforward to correct just the speakers' responses.

2) A 3D mike array like the Trinnov uses can also determine where the reflections are coming from.

At least in theory; I haven't seen enough info on it to conclude one way or the other, but perhaps its psychoacoustic moving of all speakers to their proper locations implies exactly that.

Irrelevant. What I was addressing was your comment about the inadequacy of microphone measurements due to their lack of attention to HRTF matters as a reason why the measurements/compensation is wrong. That argument is bogus and has nothing to do with the differences between physical acoustical treatment and electronic EQ.


But they do. The mic don't know what sound comes from behind. The mic don't have shoulders that effect the sound. The mic don't have ears that effect the sound.

well you need to learn a bit about digtal room correction and mics because you don't have any idea


Well, I know some bit, you can maybe tell me where I'm wrong? In a technical way.

But NIN74, that's why I'm surprised you're on the wrong side of this room correction argument. I think you'd be quite enthusiastic about its potential and far more constructive about its pitfalls. Of course it's not perfect! But nor is simple equalization, and that can be quite helpful sometimes too. Room correction is simply a more flexible and powerful superset of equalization, which also makes it more dangerous if used improperly.


The reason is that I listen to this processor with the B&W 802D and it didn't sound that hot. And that I also pointed out some problems with let the processor change the signal instead of me fixing to room for the signal.
Like I said, it can be better than a untreated room but for me, I rather fix my room and have even better sound, for a lower cost too!

Then read the AES paper for the Lyngdorf Room Correction system. The tool is based on science. The basic is that the system measures multiple points within the room to get an estimate of the power response of the room. Then for the specified sweet seat, it makes corrections which are bound by that power response. So if the correction for an individual frequency exceeds those bounds it will not correct beyond that point. In the end, their goal is not to modify the sound of a particular loudspeaker; but rather it is to minimize the effect of the room on that loudspeaker. Whether or not you like the sonic result of the technique is another question altogether, and a highly subjective one at that.

I do agree that if you don't start with the room, you've got an uphill battle. Any of these tools should have far less "work" to do in that case. However, improving the sonics of a bad room isn't a bad thing for those that haven't gone that route.

Cheers,


Yes, but at the end of the day, I listen to it and it didn't work as good as I want it to work. Like I said, some spots in the room you want to damp, some spots do you WANT to reflect, and I don't think any processor can fix that.
Hopefully a friend will borrow this to try on his Final sound speakers, then I listen some more. But right now, I'm starting to fix my room after the direction I got from my "acoustic" guy. :)

But they do. The mic don't know what sound comes from behind. The mic don't have shoulders that effect the sound. The mic don't have ears that effect the sound.
Well, since you cannot understand and/or accept a simple causal (and logical) relationship in procedures having nothing to do with the hardware, I see no reason to bother with further discussion.

But they do. The mic don't know what sound comes from behind. The mic don't have shoulders that effect the sound. The mic don't have ears that effect the sound.

"the mic don't know" but the processor do. It knows what the original impulse signal looks like and anything that DOESN'T look like that is a function of the room (and/or the stuff in it). And depending upon when those "extraneous signals arrive" (in time) one can reasonably well determine where they were reflected from.

This technology has been around long before room correction. It is similar to determining (and eliminating) the spurious reflections in radar detection.

Trust me NIN74. Well done room correction works incredibly well .... and no offense, but it is abundantly clear that you really have no idea what you are talking about.

"the mic don't know" but the processor do. It knows what the original impulse signal looks like and anything that DOESN'T look like that is a function of the room (and/or the stuff in it). And depending upon when those "extraneous signals arrive" (in time) one can reasonably well determine where they were reflected from.

This technology has been around long before room correction. It is similar to determining (and eliminating) the spurious reflections in radar detection.

Trust me NIN74. Well done room correction works incredibly well .... and no offense, but it is abundantly clear that you really have no idea what you are talking about.

Darn...I thought that I was the only one who could see through his BS

Darn...I thought that I was the only one who could see through his BS

I think there are a few of us.

I think there are a few of us.



;)

One of my best friends indeed has a TacT equalized room that I'd probably the finest room I have ever heard. He got involved 2-3 years ago and has made it a 2 hour per night obsession. He explained to me that most people install the unit use the mics then set it and forget it. He said this perhaps does 10% of what the unit is capable. ......... Simply put if one spends the time getting into the unit and doing some work the results are mind boggling.

He (You) validate exactly what I was saying. There is no free lunch. It takes an investment in time and "thinking".

2 hours per night for 3 years! I was right about the OCD part as well. And I thought I was anal!!

I'd love to hear that system. What kind of speakers does he use?

As an aside, when I was in that business, we ALWAYS got our best correction on Wilsons (usually Grand Slams) and Genesis/Infinity.

He (You) validate exactly what I was saying. There is no free lunch. It takes an investment in time and "thinking".

2 hours per night for 3 years! I was right about the OCD part as well. And I thought I was anal!!

I'd love to hear that system. What kind of speakers does he use?

As an aside, when I was in that business, we ALWAYS got our best correction on Wilsons (usually Grand Slams) and Genesis/Infinity.


he has the large Pipe Dreams with a pair of Gotham subs, VTL Siegfried and Ref 3 preamp with Meitner CDSA SE and Goldmund TT

He has his TacT dialed in most places to literally 1/10 Db. It is probably the best room I have ever heard. He literally is working 2-3 hours per night on all of the frequencies. I was in awe as to how good it sounded.

Interesting. I had heard Pipe Dreams in 5 different venues (including a friend's home) and always thought they were incredibly over-rated. One of the big and obvious issues was the integration of those 75 million 4 inch drivers to the 18 inch subs (which sounded REALLY slow). If your friend replaced the Pipe Dream subs with Gotham subs AND used the Tact to integrate them, then that could indeed be a really nice solution.

But he's still anal !!

Interesting. I had heard Pipe Dreams in 5 different venues (including a friend's home) and always thought they were incredibly over-rated. One of the big and obvious issues was the integration of those 75 million 4 inch drivers to the 18 inch subs (which sounded REALLY slow). If your friend replaced the Pipe Dream subs with Gotham subs AND used the Tact to integrate them, then that could indeed be a really nice solution.

But he's still anal !!


That is exactly what he did

I have never been so engaged in any audio room in all my years as his. Simply the best of the best and yes I too am not a big fan of line array speakers but his were like nothing I have ever heard

Where are you going Michael? I thought I saw that Austin had a dealer.Damon, I thought I had answered this but I hadn't. I'm going to Audio Systems (http://www.audiosystems.com/) in Austin. They also run this web site (http://www.usrcs.com/) about Lyngdorf products.

I think there are a few of us.


Well, if you think you will get great sound, good for you. I working on my room now and guess what...no processor. :cool:

Well, since you cannot understand and/or accept a simple causal (and logical) relationship in procedures having nothing to do with the hardware, I see no reason to bother with further discussion.


You can think that if you want, but I do not agree with you and my guy that are measuring my room do not agree with you either.

You can think that if you want, but I do not agree with you and my guy that are measuring my room do not agree with you either.

So the guy measuring your room doesn't understand that any reflected sound will arrive at the mic later than a direct path either? It's a pretty basic exercise in physics, and something for which we have sufficient granularity in time to account for.

Well, if you think you will get great sound, good for you. I working on my room now and guess what...no processor. :cool:
I don't get you NIN. You make comments about science and objectivity and its relation to audio, but then you go and make some very questionable statements about sub placement. Now you diss processors and their roles in room "equing". Do you just pick and choose when science in audio is applicable and when it is to be avoided?

I don't get you NIN. You make comments about science and objectivity and its relation to audio, but then you go and make some very questionable statements about sub placement. Now you diss processors and their roles in room "equing". Do you just pick and choose when science in audio is applicable and when it is to be avoided?

congratulations Raul you just figured out what the rest of us all know

I don't understand the big deal. NIN is clearly say, IMO, that acoustic treatment is better than DSP at dealing with room problems. I think he's clearly correct. DSP is a great bandaid when you can't fix the room. What's the problem? A lot of stupid AVS arguments are about two people looking at a gem and one saying it's greenish blue and the other saying its bluish green.

I'd clearly prefer avoiding DSP to correct the sound. But I'd also use DSP if it gives me a net performance increase. Can someone point to something he's said that's factually incorrect in this thread?

"Can someone point to something he's said that's factually incorrect in this thread?"

How about this

""The processor only hear the total sum of the room..."

I don't understand the big deal. NIN is clearly say, IMO, that acoustic treatment is better than DSP at dealing with room problems. I think he's clearly correct. DSP is a great bandaid when you can't fix the room. What's the problem?

It's not an either or proposition. You start with treatments and finish with DSP or signal processing in some fashion.

In a treated room DSP has value it will simply work on smaller issues than it would have to if it were an untreated room. For argument's sake, we'll say that a room measures as having a 15dB swing in frequency response below 150Hz without treatment. After treatment, we have it down to 8 dB.

DSP works for both, but the magnitude of the correction is smaller and it may very well be used in different locations.

I'd clearly prefer avoiding DSP to correct the sound. But I'd also use DSP if it gives me a net performance increase. Can someone point to something he's said that's factually incorrect in this thread?

I'll leave that to others.

NIN74: are there any circumstances where you would digital room correction to be beneficial?

Alimentall: why would you "clearly" prefer avoiding DSP? What's your bias against it? It's odd that you would say that given your preference in another thread towards all-digital processors. Can you conceive of any real-world situation where even a small amount of digital room correction or equalization would not provide benefit? Do you really think a room can be tuned that exactly with physical treatments alone?

Well, maybe I should say that I'd clearly avoid the room correction that I've heard this far by treating acoustically if possible. I think DSP is best used to fix the acoustically difficult or unfixable in the low frequencies. You can't fix a side wall reflection with DSP very easily. I just don't think this is worth the arguments I can understand his point. I'm not going toto argue for 10 pages about it. He's clearly a 'fix the room first' guy.

Of course DSP can be useful. But room treatment is more fundamentally important. My speakers are DSP active speakers, it's not like I'm averse to DSP! I'm saying that NIN has valid points, just not said in the way you'd all like. Or, if he's saying that no DSP is ever useful for room correction, just say "I disagree" and move on. Or put him on your ignore list for awhile. Sheesh.

It's not an either or proposition. You start with treatments and finish with DSP or signal processing in some fashion.

I didn't say it was, but if you can get the magnitude of errors sufficiently low, there's really little to no need for DSP. Audyssey can make a really good system sound worse pretty handily, for instance.

I didn't say it was, but if you can get the magnitude of errors sufficiently low, there's really little to no need for DSP. Audyssey can make a really good system sound worse pretty handily, for instance.

That's an Audyssey problem. Or the problem of the person using it.

I have been in HUNDREDS of listening rooms in the 10 or 15 years I did room correction. Many of which were dedicated to 2 channel audio, and designed by folks who clearly understood room acoustics. And I have only been in one room that was purpose built form the ground up where room correction did not make a positive change far greater in magnitude than any other component change you could name. I'm certainly not saying there are not other rooms where room correction my not improve the sound,but statistically, that would be a very small percentage.

I don't know much about the Audyssey system, but if it does not allow user intervention at a pretty granular level, it would, in my mind, not be a high end solution. I have an Audyssey chip in an inexpensive surround processor/receiver in my family room and I do not use it because it screwed up the bass....and there was not a way for me to fix it. But the Tact unit and others do allow user interaction. But be forewarned, if you do not know what you are doing, you can not only make the sound much worse, you can blow tweeters, mid ranges and woofers.

I just think there is a false assumption that whatever the effect of the DSP, that it will be better than unprocessed. I think a lot of people, such as Denon/Onkyo/Marantz are listening to sound that is worse because of DSP. It's not atypical for a sales guy to pitch whatever the result is, even when, as The Bogg said, it sounded worse to him. This is the result we had with Audyssey Pro unit. Bass was cleaner, but too lean and upper ranges were aggressive and harsh. I found it to be unacceptable as it was. They weren't willing to address it, but thankfully, they were willing to take it back. NAD's gear has the enhanced Paul Barton curve in it (which directly addressed my complaints) and it does help in most situations, but we still warn people to not assume that the result will be better and that they should use the setting, including 'off' that they prefer in the end.

I just think there is a false assumption that whatever the effect of the DSP, that it will be better than unprocessed.I certainly think that's fair. Obviously it's quite possible to screw things up with DSP, just as it's possible to improve things.

I also think there's a false assumption among some that Audyssey and/or RoomPerfect represents the full potential of room correction...

I certainly think that's fair. Obviously it's quite possible to screw things up with DSP, just as it's possible to improve things.

I also think there's a false assumption among some that Audyssey and/or RoomPerfect represents the full potential of room correction...

If the RoomPerfect solution does not allow the (hopefully well trained and very knowledgeable) user to make adjustments, then it too is not a good high end solution. But as noted previously, even with user adjustments available, if the user does not know what he/she is doing, then the chance for poor results increases dramatically.

I think the only 'safe' DSP is that which corrects only below ~300Hz were the improvement is close to a guarantee, rather than above that where it is just as likely to screw things up. Speaker correction above 300Hz? Sure. But you can't correct for the *room* above that, not in reality. Above 300Hz, you're pretty much just slapping a bandaid on top of the problem.

So the guy measuring your room doesn't understand that any reflected sound will arrive at the mic later than a direct path either? It's a pretty basic exercise in physics, and something for which we have sufficient granularity in time to account for.


I believe he knows what he is doing ;)

I don't get you NIN. You make comments about science and objectivity and its relation to audio, but then you go and make some very questionable statements about sub placement. Now you diss processors and their roles in room "equing". Do you just pick and choose when science in audio is applicable and when it is to be avoided?


Well, I go with the people that know this stuff and not the regular hifi "knowledge" :)

I don't understand the big deal. NIN is clearly say, IMO, that acoustic treatment is better than DSP at dealing with room problems. I think he's clearly correct. DSP is a great bandaid when you can't fix the room. What's the problem? A lot of stupid AVS arguments are about two people looking at a gem and one saying it's greenish blue and the other saying its bluish green.

I'd clearly prefer avoiding DSP to correct the sound. But I'd also use DSP if it gives me a net performance increase. Can someone point to something he's said that's factually incorrect in this thread?


Exactly. The point I'm making is that acoustic treatment is better than DSP, but DSP is better than no acoustic treatment :)

NIN74: are there any circumstances where you would digital room correction to be beneficial?


DSP correction is better than nothing. But if I wanted the best possible sound, I would go for fixing the room. I have listen to this processor that we are talking about and is not the impressed. Good, but better with roomfix's, IMO.

And after fixing the room, I can almost guarantee you that a PROPERLY INSTALLED AND IMPLEMENTED room correction system will further improve the room.

OK, that's cool, NIN74. Now: what's wrong with fixing the room and then applying room correction? Do you believe you're going to get perfectly flat response with room treatments alone? If so, point me to such a room because I've never heard of one one.

And if not, what's wrong with a bit of properly generated, gentle correction to further improve things?

Ah, I see audioguy had the same response I did.

I believe he knows what he is doing ;)

If his answer is strictly room treatment without additional room correction of some type, I'll just say yeah, right.

I have a heavily treated room as all members of BAAS who have been to my house know. I think my room is fairly decent BUT having heard my buddy's room which is both treated and TacT equalized I can honestly say that NIN has not even begin to understand what room equalization can do.

And after fixing the room, I can almost guarantee you that a PROPERLY INSTALLED AND IMPLEMENTED room correction system will further improve the room.


Why should it? If the room is fixed to have a low RT60 (0,25) and no problems with peaks and things like that, why should I use a processor?

OK, that's cool, NIN74. Now: what's wrong with fixing the room and then applying room correction? Do you believe you're going to get perfectly flat response with room treatments alone? If so, point me to such a room because I've never heard of one one.

And if not, what's wrong with a bit of properly generated, gentle correction to further improve things?


If you believe that one should have flat response at the listningpostition, then you maybe want to do that. But that is not what I want. I want the response that sounds most correct, and studies have showed that it is not a flat response.

If his answer is strictly room treatment without additional room correction of some type, I'll just say yeah, right.


Well, you can ask him. He will probably be at various hifi shows in the future. Just look out for this man
http://img166.imageshack.us/img166/7537/gururh6.jpg

I have a heavily treated room as all members of BAAS who have been to my house know. I think my room is fairly decent BUT having heard my buddy's room which is both treated and TacT equalized I can honestly say that NIN has not even begin to understand what room equalization can do.


Well, you say that I do not understand, and maybe so. I'm not a 100% expert on this but I have read about it from people that do have actually study these effect for many years. And I do have listen to a pair of 802D with this processor, so I do have some understanding.

But when you could not hear problems with a SET amp that produce a massive amount of distortion and will compress dynamic music with any kind of good soundlevel, I do not really know what to believe. If you cannot hear this, what else cannot you hear? But as long as you are happy, than it is fine. But just because you are happy with it, it will not be another guys choice, especially if that person are looking for as transparent sound as possible. Take care

I want the response that sounds most correct, and studies have showed that it is not a flat response.Doesn't matter what you think the response should be, you're not going to achieve it perfectly with room treatments alone. And even the small errors that are left could be candidates for room correction.

Folks: We are wasting our breath. NIN74 doesn't get it.

And Michael, the guy that was with me when you and I met a CES a few years ago (you may not remember me or him), his room actually is flat. I have both seen the measurements and done them myself. Rives designed the room WITH NO RESTRICTIONS on overall size or dimensions and it is truly amazing. Rives would not put the measurements on their web site because they thought that anyone who saw them would believe they were not real. Richard (Rives) told me this room was the flattest they had ever seen, And given they do hundreds of rooms a year, that is saying much. I don't know if room correction would further improve his room or not but if it did, it would not be by much.

Yes, I remember! Wow, that's impressive. And if Rives says it's that rare then I think we have to take his word for it. So NIN74, by all means, when you get your room's response exactly correct, by all means, show us the curves! :)

Doesn't matter what you think the response should be, you're not going to achieve it perfectly with room treatments alone. And even the small errors that are left could be candidates for room correction.


Again, you will not help with with a processor IMO. It cannot fix it so it sound natural. Like I said, the mics and the human ear hear very differently. But if you think it works, good for you, go for it. I rather listen to my music with room treatment.

Folks: We are wasting our breath. NIN74 doesn't get it.


Or it is maybe you that don't get it? Ever thought about that? :)

OK, that's cool, NIN74. Now: what's wrong with fixing the room and then applying room correction? Do you believe you're going to get perfectly flat response with room treatments alone? If so, point me to such a room because I've never heard of one one.

Keep in mind, Michael, that a perfectly flat response at the listening position doesn't sound natural. The sound from the speaker should be perfectly flat. The sound of the room should be subtle, but normal. The sound at the listening position should be realistic. We're used to hearing room. The key is not to eliminate the room, but only to eliminate obvious problems. Most correction is too heavy handed and attempts to fix things that should be left alone.

If you do room treatment properly, it is far more likely that further EQing will be damaging or unneeded. A really good DSP device will listen to the speakers first, correct them to be flat at the speaker, then measure the room a few ms later for damaging room modes.

I have to say, NIN maybe at the extreme on his aversion to DSP, but I understand and respect it and don't see why he has to 'get it'. DSP room correction is at best an option, it certainly isn't required to get great sound.

Doesn't matter what you think the response should be, you're not going to achieve it perfectly with room treatments alone. And even the small errors that are left could be candidates for room correction.

There's no such thing as a 'perfect' in room response. There is no *need* to have a perfectly 'flat' response in the room. This doesn't exist in nature, we're not used to it, we certainly won't hear it outside of a controlled environment. If you build a 'perfect' room with 'perfect' DSP correction, it won't sound like live unamplified music, it will sound like a pair of speakers that can't ever reproduce the real thing.

If you build a 'perfect' room with 'perfect' DSP correction, it won't sound like live unamplified music, it will sound like a pair of speakers that can't ever reproduce the real thing.Only if the recording was made in an anechoic chamber. The idea is to reproduce the ambiance of the original recording site unobscured by the acoustic fingerprint of the listening room.

DSP can't remove in room reflection and ambience. Only absorption can. So if what you say it true, NIN is more correct than not.

Besides, 2 speakers can't reproduce anything like reality unless it's 2 musicians standing 6-8' apart from each other.

If you build a 'perfect' room with 'perfect' DSP correction, it won't sound like live unamplified music, it will sound like a pair of speakers that can't ever reproduce the real thing.

DSP can't remove in room reflection and ambience. Only absorption can. So if what you say it true, NIN is more correct than not.

Besides, 2 speakers can't reproduce anything like reality unless it's 2 musicians standing 6-8' apart from each other.First, I took your statement literally and, in particular, the use of the word perfect. Second, I did not assume that the perfection was achieved only by DSP but also by the process of building (and treating) it for the purpose. The result would, in this thought experiment, remove room reflection and ambiance or reduce them to inconsequential levels. Unfortunately, it would be a disaster for 2channel reproduction which relies on a contribution from listening room acoustics to simulate the ambiance of the recording site. Multichannel would be more successful in this room.

I understand, I just don't think this is worth arguing over since it's constantly evolving. Having first hand experience with this, I can understand NIN's point and don't think he should be necessarily steamrolled into believing that DSP is really all that useful in a well done room. I think the goal of any room should be to not require DSP at all.

I think the goal of any room should be to not require DSP at all.Ideally.

Folks: We are wasting our breath. NIN74 doesn't get it.

And Michael, the guy that was with me when you and I met a CES a few years ago (you may not remember me or him), his room actually is flat. I have both seen the measurements and done them myself. Rives designed the room WITH NO RESTRICTIONS on overall size or dimensions and it is truly amazing. Rives would not put the measurements on their web site because they thought that anyone who saw them would believe they were not real. Richard (Rives) told me this room was the flattest they had ever seen, And given they do hundreds of rooms a year, that is saying much. I don't know if room correction would further improve his room or not but if it did, it would not be by much.

I had hoped that I wouldn't need to add any processing to the sound in my room by having Rives design a level 3 room for me. I was limited by my ceiling height (7'10" finished) so they did the best they could with what they had. I was a bit surprised to learn it was the smallest level 3 room they had done - I didn't think the room was all THAT small at 17ft wide x 30ft long (they used 24 ft of it for the room).

The measured response above 300hz is quite good with no significant peaks or dips. Below 300hz is not so good despite extensive bass trapping etc... The measurements don't tell the whole story because the sound in the room can be quite good and just takes a bit of work with speaker placement. I haven't found what is best yet, but once I've gotten it a bit better I'll have Richard Rives come out for the calibration and measurement phase. I have an Accuphase DG28 digital eq which I could use between cd player and dac if needed.

Bottom line is that even with good designers and equipment it still isn't a guarantee that you'll get "perfect" (whatever that means) results without the need for further tweaking with eq or other means.

DSP correction is better than nothing. But if I wanted the best possible sound, I would go for fixing the room. I have listen to this processor that we are talking about and is not the impressed. Good, but better with roomfix's, IMO.

DSP correction in an untreated room requires lots of patience and careful tweaking. Not recommended for the faint of heart.

Ideally the room should be treated first, and then DSP applied to fix the (minor) flaws that are not feasible to fix with room treatments (due to cost or practicality - some people may prefer to have some furniture in the room, you know :) ).

Peter

Ideally.

So far, I'd say that the systems trying to deal with mid and high frequencies do more damage than good in a decent to good room. There are downsides even to trying to force a passively crossed over speaker be accurate. When DEQXing many speakers, I found that simply making them more 'accurate' didn't necessarily make them sound better. Sometimes just different. Other times, worse. The magic to DEQX had little to do with making a speaker more accurate, it had to do with bypassing the passive crossover and optimizing individual driver impulse response. Frequency response is only one portion of performance. If you cut the musical signal 6dB in one area because of a room peak, you're removing music and allowing distortion to fill in the hole. The distortion to music ratio is still high. The problem with DSP is that it's hard to make small gains without having even larger added problems. If your room or setup sucks, well, it's easy to make large gains with relatively small amount of added problems. DSP room correction isn't *really* a high-end thing to do, IMO, because it's putting make up on a pimple, not preventing it.

DSP room correction isn't *really* a high-end thing to do, IMO, because it's putting make up on a pimple, not preventing it.:D Without cosmetics, I don't think we'd tolerate HD cinema.

So far, I'd say that the systems trying to deal with mid and high frequencies do more damage than good in a decent to good room. There are downsides even to trying to force a passively crossed over speaker be accurate. When DEQXing many speakers, I found that simply making them more 'accurate' didn't necessarily make them sound better. Sometimes just different. Other times, worse. The magic to DEQX had little to do with making a speaker more accurate, it had to do with bypassing the passive crossover and optimizing individual driver impulse response. Frequency response is only one portion of performance. If you cut the musical signal 6dB in one area because of a room peak, you're removing music and allowing distortion to fill in the hole. The distortion to music ratio is still high. The problem with DSP is that it's hard to make small gains without having even larger added problems. If your room or setup sucks, well, it's easy to make large gains with relatively small amount of added problems. DSP room correction isn't *really* a high-end thing to do, IMO, because it's putting make up on a pimple, not preventing it.

John,

Having finally played with the DEQX box this past weekend, I'd suggest you get more realistic about what it does and doesn't do. There are MANY important limitations in its use and operation. What it does it does well, but the tool set and inputs are limited.

Guess what? That's the same story for most of the automated systems. The question is how good is the logic and averaging of the system, and IMO the most important question is how much input and oversight the user is given to catch when it does something un-intended. While I haven't played with them in quite a while, I believe the Tact and Lyngdorph systems both have a significant amoung of user input, which allows for a more refinement, but also requires a bit more knowledge of what is actually going on in the system.

BTW, not really THAT against DSP for FR correction, but I think NIN's POV has some validity. I am not willing to accept current DSP systems as the end game. If a CD player or speaker wire did that much damage to the sound, it would be considered to be snake oil. I'd say room correction is promising, but a work in progress. At some point, people will likely be choosing between algorithms or there might be 2 or 3 different room correction algorithms built into a receiver. You might be able to choose the algorithm you want from a download option for a given product, like a program on a computer, possibly even with a 'trial' period, such as Sonos does with its 4 music services. Try the algorithm for a week, then try another, then another, then purchase the one you like.

Having finally played with the DEQX box this past weekend, I'd suggest you get more realistic about what it does and doesn't do. There are MANY important limitations in its use and operation. What it does it does well, but the tool set and inputs are limited.

Hah! That's like saying you finally played with a guitar for a weekend and saying it's limited. What I'm saying here is that it's strength is not its FR or room correction capability, that these things are just icing on the cake and may not even be that helpful in a lot of situations. Bypassing passive components, optimizing driver response BEFORE it its crossed over is a big deal. Optimizing system dispersion is a big deal. It's not DEQX that is so amazing, it is doing these things that are more important than little FR corrections.

Keep in mind, Michael, that a perfectly flat response at the listening position doesn't sound natural. The sound from the speaker should be perfectly flat. The sound of the room should be subtle, but normal. The sound at the listening position should be realistic. We're used to hearing room. The key is not to eliminate the room, but only to eliminate obvious problems. Most correction is too heavy handed and attempts to fix things that should be left alone..


I so agree with you! To many think that you should have a flat FR at listening position but that will not sound natural. It sounds better like you said. :)

Hi

I do not use (yet) Electronic Room Correction in my system. Yet Electronic Room Correction is the future of Accurate Music Reproduction. Some of us may afford (not necessarily in the financial sense) to build a room "just" for music or HT. For most most people, however, the room remains a compromise between livability and acoustic performance ( I am staying away from aesthetics and SAF, spouse Acceptance Factor). For these people and those whose rooms can not be properly treated, this is a very good option.

I do however tend to share one of John position.. Room Correction is to be left "downstairs" where the contribution of the room basic geometric features are of the same order of magnitude as the wavelength of the sound waves. i-e everything under 500Hz if we need to choose a nice number... Up there >500 Hz Electronic Room Correction have tended to do more harm than good...
Another point is that none of these devices are as "automatic" as many users would wish... They require a degree of knowledge that is far from trivial to not cause harm to the sound for the most part... I remember a TaCT system where the system "wanted" to apply a small correction in the lower treble region.. This made all horns sound like muffled woodwinds.. the most interesting aspect was that the correction was quite subtle about 1 dB aboud 4~5KHz .. as I recall it now it could have been less...

Last but not least: The Flat Frequency response curve dilemma; It seems at first like what would be needed in an accurate system.. Yet there is much more to accurate music reproduction than ONLY flat frequency response as measured from a given microphone...Most people involved in Audio reproduction would tell you that many if not most systems that measure flat (in frequency Response at least) do not sound “good”. I have noticed that the best Room Correction do not necessarily go for “flat” only...
There is a lot more that could be said about these.. I'll stop there

This has been an interesting discussion. I have a 20' x 17' room with a pair of Vandersteen 5As (source is a Linn Unidisk) and the room is doing a number on the sound of the speakers. I have added room treatments for bass trapping, diffusing, and reflecting the problem areas (with the help of Rives). However the room still suffers from some low end peaks and valleys.

Recently I was given a Lyngdorf RP-1 to try and when I get some time next weekend I'll set it up and give you my impressions. I don't expect perfection, just an improvement that justifies adding the equalization.

I would also be very curious to hear Michael's impressions of the Lyngdorf set up in Austin.

Hah! That's like saying you finally played with a guitar for a weekend and saying it's limited. What I'm saying here is that it's strength is not its FR or room correction capability, that these things are just icing on the cake and may not even be that helpful in a lot of situations. Bypassing passive components, optimizing driver response BEFORE it its crossed over is a big deal. Optimizing system dispersion is a big deal. It's not DEQX that is so amazing, it is doing these things that are more important than little FR corrections.

not to defend mark here as he surely does not need it, but it is more like a really good session player picking up another model of guitar and saying this thing is neat, it has some neat sounds, but overall, it is limited in its sound.

:D Without cosmetics, I don't think we'd tolerate HD cinema.

Funny you say that because it is EXTREMELY well documented that HD caused a truly paradigm shift in both makeup and lighting in hollywood. both in the studio and on the red carpet.

Pre HD, makeup tended to be really caked on, and lighting was to the extreme in order to make a certain look stick. now that HD does so much better with so much less, lighting has had to back way the F off to almost subdued. and makeup... well lets just say that this look is out!

http://www.theage.com.au/ffximage/2007/07/22/js22tammy_narrowweb__300x431,0.jpg
Crap. Could not find a pic of Garth Brooks from the SNL sketch "Old French Whore"

But i did Discover that Bob Lee (QSC) is a Hartford Whalers fan! (gotta love Google!)


However the audio DSP carries the analogy forward, it is a tool that in the right hands, used carefully and with precision, can do some wonderous things...

Like this
http://www.asiacarrera.com/makeup/makeupface.jpg

To this
http://www.asiacarrera.com/makeup/eyescolors.jpg
Full props to the owner of the website that i unceremoniously stole these from, the amazing miss Asia Carrera.

An update on my experience with the Lyngdorf RP-1:

As I said earlier, after treating my room at the locations the acoustics books, the ETF room analyzer program, and the guys at Rives suggested, I still have more ups and downs in my room response than a bipolar driver on a mountain road. I had a chance to try a Lyngdorf RP-1 to determine if that would further smooth my room from hell.

The RP-1 was very easy to connect, calibrate, and set up. It has a bypass function so it's easy to A/B the sound to get a feeling of the difference with and without room correction. The RP-1 did make the room response better (not flat) and, after listening to several familiar music tracks, it was clear the RP-1 made a positive difference. The sound is smoother, more natural, and the soundstage opened up.

The RP-1 is not a panacea and may not be for everyone. It really depends on the room, and the worse your room response is, the bigger the RP-1 benefit. It sounds like many of you have good room acoustics to begin with and, for you, the RP-1 may not be worth the money. But in my case the digital room correction made enough of a positive difference that I will be keeping the RP-1 in my system.

If you have a room that sounds like Tammy Faye looks, Room Correction of any kind won't make it sound (look like) Asia Carrera (even without makeup).

MikeTz ... I had a similar experience with Tact gear a couple of years back.

In a purpose built room with hard core two channel gear the improvements gained were not worth the costs imposed: all in it was "subtractive"

However, in my Den, with bay windows and asymmetric everything the improvements were amazing.