Simplified REW Setup and Use (USB Mic & HDMI Connection) Including Measurement Techniques and How... - Page 25

Hey Jerry and jkasanic,

You've offered some very good advice here.

I need to clarify a few things and praise you once again.

First, thank you so much for creating and displaying these graphs the way you did. They are at the proper scale and most importantly, they are large enough to see without having to zoom in my whole browser window and/or download the picture and manipulate it manually to be able to read the numbers.

I would appreciate it so very much if everyone posting graphs would use Jerry's examples here as all but one little thing is absolutely perfect. The right scale, the right amount of data, smoothing, and size is all perfect! I just don't have the time to manually download things (especially as I assume shortly there will be a lot more posts to analyze) and rescale them.

However, on the FR graphs you are using a 10db scale and that really makes things look a lot better than they are and makes it a lot more difficult for me to see. Plus, I may forget that it's not the normal 5db I'm used to looking at. You have it set to show in 5db vertical increments on the waterfall and etc but 10db on the FR and we need consistency.

Now, with that being said, I just read about 1000 posts in 20 different threads and it's 6:30 A.M. here, so bare with me, but I'm not so sure about what you've stated re the ETC measurements... Don't recall seeing enough data in the last few posts (maybe in another post a few pages back??) for you to come up with some things, so I want to take a moment to explain exactly what he should be looking at and how to calculate to find what's causing the specular reflections.

We see the first reflection at about .5ms which is almost certainly from the speaker cabinet itself. Depending on how the mic is mounted/placed it could even be from that, but I suspect diffraction effects or the speaker grill, depending on how it's designed (take more measurements without the grills), etc. This does need to be addressed, however.

Second, we see a very high gain specular reflection way too early at around 3ms. The way to figure where this is coming from is to multiply 1.13 times 3ms in this case. (Always multiply the timing of the reflection by 1.13) and ADD that to the "actual" distance between the mic and the acoustic center of the speaker. If the speaker uses a D'Appolito array then you can use the tweeter. That's how long the path of this reflection is traveling in total. You can then mark on a tape measure or cut a string to this length (adding a few inches at each end to be able to tie the string, but making sure the marks on the string are at the exact added distance to the actual distance between mic and speaker in the end) and pull the string taut in ALL directions until you find all the surfaces the string touches. Then, one by one, add an absorber or large piece of insulation to that area and remeasure until the reflection is at least -20db in gain.

Do this for all reflections out to about 20ms.

In a lot of conversations we hear that either all reflections are bad or in some alternative points of view we hear they are helpful and needed.

My philosophy (based on acoustical models that have been around for decades and folks much smarter and with much more experience than me all but unanimously agreeing) is that "high gain" and "early" reflections aren't good and in fact will cause smearing and not give you some of the main psycho acoustic benefits we are striving for in our small acoustical spaces, such as making them sound like larger rooms!

However, a lot of people that follow this philosophy stop there. The fact is, all reflections are NOT bad! In fact, they are necessary! Depending on the size of your room and your level of commitment, anywhere from about 12-20ms (larger rooms up to 25ms) should have a termination of the effectively anechoic space we are creating by reducing the early reflections to -20db in gain relative to the direct sound. There should be reflections after somewhere between 12-20ms but they should be diffuse and dense and not just one or two here and there.

This is difficult to achieve and if you go around filling the room with tons of absorption it could be almost impossible.

There can be too much of a good thing. So, test each spot (mirrors and the "mirror trick" are USELESS for this very reason) relating to the spike in the ETC and ONLY place absorption where it is absolutely necessary to tame that spike.

There are other methods that don't require any use of absorption in the specular region such as reflection/deflection/diffusion but those are a bit more advanced topics we'll touch on later.

As far as the frequency response, it is true you have a null/room mode at 40hz. Due to the wavelength (very long) at this frequency, moving "just a little" to the left/right isn't going to do anything and will just make other things worse. Symmetry is very important.

If you had two subs though, we could effectively cancel this null through placement.

Invest in another sub.

If you cannot do that, then through placement of the sub and tweaking of the phase (distance controls, measure in one foot increments starting 5-6' below what Audyssey found and going to 5-6' above) you will still be able (most likely) to smooth things out a bit more.

Make sure to do all this with Audyssey OFF.

As for the waterfalls, it looks like unfortunately Audyssey made things worse in the very low frequencies. Luckily, in the range from 20-300hz (some noise is showing and you might want to raise the bottom limit to 42 or 43db just to make it easier to see the "truth") you don't have a lot of problems that will be extremely difficult to fix. The biggest one is of course between 30-40hz and regular velocity based (pink fluffy) absorption isn't going to work well at that frequency, so placement, phase, and EQ are the best bet for that one unless you don't mind spending some money and getting some pressure based tuned traps for 30-40hz.

Audyssey, by taming the peak at 30hz helped cut down the ringing a bit, but it's still too much and you need bass traps for the rest. 40hz was made worse by it boosting the null in trying to fix it. This is where another sub and/or placement could help a ton.

The ETC's for the L and R channels (you did measure only one at a time, right? Test sweep tones coming only from the L channel for the measurement marked L, right?) are very similar. This is a good thing. The example I gave for the first reflection (diffraction most likely) and the second one at 3ms applies to all the others that are peaking above -20db as well. Just multiply 1.13 by the ms of the reflection and add it to the physical distance between mic/speaker then pull a string taut in all directions, placing insulation/absorption at each spot one at a time, measuring in between, until you tame the peak. You have to do this for all seating positions that you care about and you have to do this separately for the L and R channels though, ok?

So... You have some work to do. I can't wait to see some results!

I'm sure I've missed a few things and hope I haven't confused you but we now have a dialog going so feel free to ask more specific questions and I'll be more than happy to help you.

Hope this helps,

--J

They most definitely are!

In fact, it's the biggest reason why we want to tame high energy early reflections.

When you have high gain early specular reflections it will smear the sound.

If you go and get rid of ALL the reflections though, your room will sound dry or dead and lifeless. In fact, getting rid of (or taming all reflections down past -20db) all the reflections would make your room effectively anechoic and I can assure you that you don't want that.

There has to be a happy medium. You definitely want symmetry in your room and your measurements and you want a combination of an effectively anechoic "period" of time terminated by around 20-25ms (a range of 12ms to 25ms is fine depending on how much of the effect you want, how big the room is, and how much time/effort/money you're willing to spend) with a strong reflection about 12db in gain relative to the 0db starting point at 0ms is the goal followed by steadily decaying diffuse reflections past that.

That will cause a psychoacoustic effect that makes your room seem spacious and much larger than it is plus your system will then sound very clear.

Just as in the modal frequencies you don't want long decaying frequencies as the bass will sound "muddy" in the specular region (above modal, which is what ETC measures) you don't want to muddy up the sound with sparse high gain early reflections

As you may continue to research and learn there are some detractors from this approach and the most famous one is Floyd Toole.

However, both for production and reproduction in critical listening rooms it is pretty widely accepted that the methods I'm teaching here, which lean towards (approaches) a LEDE room (which, folks, does NOT mean live end dead end) will make your room sonically, well.... sound!

There are several different approaches to designing rooms. I can't say definitively that there is a "wrong" way or a "right" way but I can say what I'm teaching here is proven and a lot of the principals for the different listening models are the same regarding similar decay times throughout the audible range, symmetry, not making the room too dead by using too much velocity based absorption (insulation) and having a relatively flat frequency response.

It seems as though the main differences in room models all comes down to reflections, whether they should exist, where they should exist, at what relative level, etc.

A lot will depend on your individual tastes, your room, your equipment, and your goals, but I honestly cannot see anyone going "wrong" with what we're trying to accomplish here.

I hope this helps and feel free to ask some more specific questions which I'll answer to the best of my ability.

Thanks,

--J

This measurement looks great! There is no doubt about that.

I think it's always best to reach for the stars. The higher you set your goals (within reason, of course) and the more you work on your room, the more you will "approach" your goals and the better the results.

With that being said, if you look at the graph on a vertical scale in 5db increments it won't look as good.

If you look at it with Audyssey off and always totally unsmoothed, it won't look as good.

Plus, remember, the FR is but one measurement and in the modal region, what is far more important is to have even decay rates that don't vary too much from the specular region (higher frequencies).

We can only tell that from a waterfall.

With that being said, I think a more realistic target should be +/- 3db. Any time I set up a system/room that's what I strive for. In different rooms, with different equipment, and different budgets (read smaller) this isn't always possible, but most of us that are reading this thread have time to devote to this and it is our hobby/passion so I absolutely believe in keeping the goals set high, but attainable.

With enough EQ and on the proper scale almost any FR can be made to "appear" totally flat, but the real test is to see the waterfall and look at the decay times and any potential ringing.

I'd much rather have a FR that is +/- 5db for instance, yet overall even decay rates that are similar to the higher frequencies than a room that appears to be totally flat but has awful ringing. It's all in how you look at things and whether or not you want pretty graphs or a great sounding room.

I prefer both!

BTW, you can absolutely get rid of the effects of that null, at least in one position, pretty easily by simply raising a subwoofer off the ground.

I had to do the same thing for a null in my own room and decided to put one sub centered on the back wall on top of the riser and now you don't even see evidence of the null in the MLP. It required no further EQ or trapping of any kind as the riser is a bass trap in itself and the sub is now 15" off the ground!

Placement is key. You have some very capable subs, my friend. I've seen your room and your equipment and you should be proud.

Before EQ'ing that 90hz null away (or trying) with your new toy coming soon, I'd seriously consider trying to raise a sub off the ground, first.

--J

Remember, ASIO is ONLY for HDMI connections.

Otherwise, use Java and there is no need for ASIO.

The USB mic is the INPUT device. ASIO has to do with the OUTPUT device and is only if you use HDMI.

Using USB and HDMI is not exclusive. You can use a USB Mic (with Java drivers) and still hook up the output the old way. If doing this, you also don't need an external sound card because you won't be using full-duplex so there is still nothing to buy but the mic itself.

I know this may be cleared up for you two by now already, but I just want to make certain everyone else (and future readers) understand this.

Thanks,

--J

I strongly agree with this for you, Theresa.

Just remember, if for now you'll be using the Omnimic for testing and to become familiar with REW, that's perfectly fine, but if you are going to use the CAL file, you need to point your mic at 0 degrees, straight towards your center channel speaker from your MLP. Do NOT point it up towards the ceiling with the CAL file loaded as it was only created for 0 degrees.

If you end up becoming a convert and you want absolute measurements instead of just relative measurements and also want some nice equipment to use with testing your custom built speakers, I STRONGLY recommend the UMM-6 mic.

--J

Is this unsmoothed?

Is this with or without the subs, too?

What is the crossover set to for this measurement?

The good news is, if this is without sub, where the problems exist, they are easy to fix with inexpensive velocity based absorption. You are a perfect candidate for some SuperChunk style corner traps made from inexpensive R30 insulation and for under $100 and about an hour for each of the 4 corners in your room (yes, there are actually 12 corners, but you have to start somewhere...) I bet these particular problems would be all but gone.

Is this with or without Audyssey?

Could you import the impulse in REW and then generate some graphs from that or at least post the mdat file?? It'd make it a whole lot easier for me to read and offer suggestions, if you're looking for any.

--J

I can't believe this!!! Ahhhhhhhhh! I was one of the first to find out about this, started the thread, but due to timing don't think I made it in this batch because I haven't received any info!

You all are gonna have your mics before me!

Oh well, such is life I suppose.

Wonder if that Mini DSP is still available from Audioguy?? Is it?

I obviously have a calibrated setup but in order to troubleshoot and be on the same page as everyone else I do want to own both of these mics.

If anyone would like to trade places in line, lol, let me know.

--J

The truth is, I don't yet have a USB mic! I'm waiting just like everyone else.

However, John would know! He's the author of REW! So I'd go with whatever he says.

Sorry I wasn't much help here. I honestly would've tried to calibrate it/set the in/out levels like I have done with every other mic I've ever used if not for reading this post and have to admit I don't fully understand the implications of "not" doing this with a USB mic, but until I get one in hand I just can't test it or figure it out.

I'd love a bit more explanation myself on the matter. Would love to know the "why" behind this and what, if anything, it changes/alters by not doing this with the USB mics and why it is not necessary and whether or not it is not only unnecessary but also suggested against doing it or doesn't matter either way??

John, are you there?

--J

I love you, Keith.

Let's revisit this NFW statement regarding reading some books a year from now...Maybe 6 months even, lol!

I'll teach you everything I know if you wish, but if you are truly passionate or become passionate about this, especially once you realize that you're not going to be able to go much further in gear purchases due to the quality of gear you already have and especially once you realize truly just how much of a role the room (by hearing the differences for yourself, in your own room, not just understanding on an intellectual level) plays in your ultimate enjoyment with your system, I can absolutely see both you and Jerry deciding to really get into this, just as I did several years ago and start reading the texts for yourself and learning at your own pace.

We'll see.

--J

While I started the thread with the initial intent of catering to those users who wanted a setup approaching plug-n-play for the input side without needing a whole lot of other equipment and to explore the new opportunities in REW to use HDMI for output, the real goal is of course analyzing and improving our rooms and soon, that's the direction in which I expect most of the discussions to head.

With that being said, as long as we're not offering tech support for all kinds of setup questions not related to the USB mics and/or HDMI output (the reason being there are already tons of threads for this over several different forums covering this ad nauseam) so we can keep the thread focused as much as possible on improving our listening environments and overall experience, I welcome all the graphs users of the "old way" wish to post and will offer all the help I can to all users no matter the physical connection, assuming that part is already done.

Hope this clears up my intent at least. However, it's everyone's thread and you may proceed how you see fit, of course.

--J

I do believe goals should be set.

I think the goal should be +/- 5db without EQ and +/- 3db with EQ. Unsmoothed, of course. This pertains to the bass frequencies only.

I think the standard +/- 3db for the specular region is fine as a goal and with EQ is mostly achievable, but make no mistake, one of my major personal goals for this thread and every system I set up is to achieve these goals as closely as possible WITHOUT EQ.

There are many fine systems both in the production and reproduction world that would be honored to achieve a +/- 3db unsmoothed, un-eq'd room. It's hard to do, in some rooms more than others, but absolutely CAN happen.

I've actually given this a lot of thought well before it just came up in this post.

While the goals need to be attainable they also need to be specific and have reason.

If met, they need to show that considerable attention and effort was made to the system as a whole to attain the goal set forth in the beginning and I think these figures will accomplish all of the above.

I'd like to see your FR and Waterfall with and without Audyssey, Keith.

Yours too, Audioguy.

We can always tweak the goals to individual's tastes, rooms, and budget.

Also, a lot of folks, myself included, set a house curve with a rising bass response similar to what you'd see using Dynamic EQ (I don't have that on my Denon 5805CI but haven't found anything that I consider a true "upgrade" from it other than the Denon AVP which is out of my budget for now) but it's important to start flat to know what you can accomplish and what you have to work with, of course.

There's nothing wrong with adding a little spice or flavor as long as you start with reference or as close as you can get and hopefully we'll all get a little closer with REW's assistance.

--J

While overall they look somewhat consistent, are you absolutely sure they are both smoothed the same?

It appears the OM measurement might be smoothed at 1/24th yet the REW measurement looks unsmoothed.

It could just be me, but I studied both images for a bit and the vertical scale is the same (pretty close) as far as the space/lines in between each 5db increment yet the REW graph shows +/- 5db MORE variation than the OM graph which tends to show they are not to the same scale re smoothing.

Either way, I wouldn't worry about it. I doubt you got the mic in the exact same position, on the same day, and you are using two different systems, etc.

REW is much more powerful and a lot cheaper, so I wouldn't worry about it going forward too much. Just curious re the absolute scale/smoothing between graphs.

--J

I'd give almost anything to get to 5hz with a bunch of output, too! The problem is, I have a 4500 cu ft concrete bunker! I have a wonderfully flat response and some of the prettiest charts and graphs I've ever seen, but.... I doubt I'll ever get much output below 20hz as I have no modes to support below that and with concrete floors I'll never get that true slam and feeling in my chest that I crave.

I will say this... For folks like me that either have very large rooms, and/or concrete floors, and/or not enough budget for the awesome subs Keith has, I recently installed a Buttkicker LFE and although I'm still fine-tuning it, there has been a huge smile on my face over the last few weeks.

I've actually installed them for others before but always discounted them and never spent time with them other than initial testing.

They work wonders for folks with my situation and I strongly recommend tactile transducers if you can't get it the "real way" like Keith has.

So jealous of Keith!

It can be calculated and is different for every room. It has to do with the height of the room, the mode that creates, and when you calculate that, you can figure out the placement.

There is an Excel spreadsheet on the Harman web-site that allows you to input your room dimensions and it will show you, graphically, where your modes are and at what area, both graphically and printed out in specific hz vs ft and inches where the modes are strongest, weakest, and mid-way.

It's pretty neat and a great tool to be able to visualize best placement for speakers/subs and listeners in the room.

It's a starting point, of course. You will have to measure and it won't be perfect as it assumes true boundries of thick concrete walls for instance, where you may actually have openings, or only one or in some cases two layers of drywall and mass is critical when trying to calculate modes, as is symmetry/rectangle room, but it is always pretty close and I use it a lot.

I'll post the link when I have time to dig it up later unless someone else beats me to it.

If I knew the height of the ceiling and the height of the listener's ears, I could tell you approximately where to place the sub vertically to negate the effects of the null in that position, but would need more detail.

Find that spreadsheet on the Harman web-site and you can see for yourself. I got lucky and in my case only had to raise a sub (it only took 1 and I have 4) 15" off the ground and I already had a 12" riser for the second row in a dedicated theater, but it can be done in any room.

--J

I think I covered most of these questions in my previous post, but let me know if I missed anything.

Jerry is on the right track here. What is your ceiling made of? If for instance it's in a basement and is a drop ceiling, you need to measure to the sub floor above as acoustically the ceiling doesn't even exist. That could be an explanation for the discrepancy between the 62hz and 75hz. That's just one example, of course.

For all but your first axial mode you can pretty easily treat the other ones with velocity based absorption.

In looking at the size and layout of your room, you are a perfect candidate for cheap and easy Superchunk style bass traps.

If possible (and it's easiest) I'd simply go buy R30 insulation (15" x 300" x 9.5" thick rolls at Lowe's for $15.87 last time I bought it a month or two ago) and make a soffit style trap in each corner. You could use two or four pieces, hanging from ceiling to floor. I use 4 pieces for a roughly 18x30" trap. This way you don't have to cut a bunch of triangles and support them so they don't compress (you don't want compression - you need it to stay as fluffy as possible) and you'll get good absorption with this type/style all the way down to 40hz.

Depending on your decay times and what it takes to treat your reflections (need you to try and clean up that ETC first) you may want to get some Contac brand self adhesive paper and adhere it directly to the soffit insulation (which will be hanging in a simple frame made up of 1x2's or 2x2's) so you don't over absorb the highs and the trap becomes a true bass trap instead of a huge broadband absorber.

If, though, you don't end up needing a lot of insulation to clean up the ETC and your room is over 300-400ms at an overall/average specular decay rate then you can do without the Contac paper as you'll want to bring those decay rates down a bit.

I've yet to see a room that cannot benefit from absorption in the modal region though. So no matter what, I'd build some inexpensive and easy floor to ceiling bass traps. You have 12 corners in your room, remember. Do the 4 main corners first, measure, and let's go from there.

You can buy them too, if you have more money than time and/or DIY skills, but... Be careful. If you're going to buy products make sure you get products that perform well and have been independently measured.

I recommend GIK Acoustics (at this time - more to come on that later) as they are honest, I've worked with them many times before, they have great performing products, a fast turnaround time, great looks, and quite frankly the cheapest prices, in some cases by far compared to any other company currently on the market today) and specifically the Soffit Trap (still a whole lot cheaper to build yourself though) the Tri-Trap, the 244 bass trap (which I believe should be used as broadband reflection panels to clean up the ETC more so than actual bass traps other than maybe some filler for problems with higher frequencies) and then if you still have problems you need to take care of in the lowest frequencies, they have Pressure based absorption called Scopus Tuned Traps that perform well (you'll need more than a few though) that will take care of your lowest modes and these type are NOT easy to build. It can be done but you need some good skills and a lot of time and patience.

I talk more about this in my previous post, but remember, for your 40hz width mode, if you had two subs, one on each side wall, they would combine to effectively produce 40hz right in the center of the room, which is your current MLP (and the best place for it as moving it just a bit isn't going to make a difference at that frequency) and your null would be gone!

I strongly recommend investing in a second subwoofer or upgrading if possible and buying two new capable subs.

Without knowing your budget (both money and time) and what exactly you hope to accomplish it's a bit difficult to offer any more advice at this time.

Hope this helps,

--J

Hi Nyal,

First I wish to thank you for responding in a civilized manor and without getting defensive.

I've read a lot of text books in my time, I've spent a lot of time on forums, and I've been involved in different aspects of business for awhile now, but no matter how much one reads and learns, experience counts the most in my opinion.

Based on what you stated in the text above, it seems as though I may have less than 10% of your real world experience at this point in my life and career, however, I do believe strongly in continuing education, gaining more experience both for knowledge sake and in that it means my bottom line continues to grow (I have work).

I'm sure over time my ideals may change a bit as I continue to learn and grow and I hope I never become a crotchety old man stuck in his ways.

But for now, I only have the education and experience I've gained so far to go on and have to respectfully continue to disagree with just a few of your ideals regarding the targets for 2-channel audio expressed previously.

I do respect where you're coming from and hope you understand that while I have some different viewpoints on certain aspects of what you believe, I don't know that either of us could say the other is "wrong" as all it boils down to is what make the customer happy.

For this thread I want to introduce folks to standard ways of doing things that aren't challenged by most and even if certain goals aren't totally met by each person, I know that nothing I'm teaching is going to make their rooms sound worse. There will always be room for improvement, but at least I'm doing no harm.

I'm sure through your experience you have found numerous reasons to come up with your own way of doing things and go down your own path, so to speak. At this point though, with my level of experience and knowledge, I simply feel more comfortable in teaching what I've learned and know works and for the most part is widely undisputed.

So I guess what I'm saying is, welcome. There is room for many different theories on what is "right" but the most important thing in my opinion is for one to decide what that path is going to be and follow it. If goals are set and worked towards to achieve them by passionate audiophiles, they will simply learn a lot along the way and enjoy their systems that much more and that enjoyment and knowledge gained will last a lifetime.

I'm glad to learn there is a typo in your document as quite frankly I mainly took issue with two of your points, one being a +/- 10db window is a "goal" and is acceptable, however, now realizing that is supposed to read +/- 5db I wholeheartedly concur. We are on the same page.

Where we remain opposed however is in regards to reflections. I never once stated all reflections are bad. In fact, I believe they are absolutely necessary.

I do believe that high gain early reflections are absolutely detrimental. I believe they cause smearing and muddiness as I've heard it myself. I also believe that nobody likes to listen in rooms approaching anechoic conditions therefore reflections after a certain termination point are necessary and they create the psychoacoustic effect of making the room seem larger than it is. Therefore, reflections become necessary, after a certain point and to a point, just not random uncontrolled reflections.

When creating a room that has a small period (12-25ms depending on the size of the room, budget, goals regarding focus on 2-channel or HT, etc) of low gain early specular reflections around -20db terminated by a high gain (around -12db or more) specular reflection and followed by a diffuse and infinitely decaying rate of further reflection, the direct sound will be heard, clear, no smearing or muddiness, and the room will sound spacious and live.

There are of course many other factors that if are not addressed will cause this effect to collapse, however, and I believe we are in agreement on most of them.

I don't think the goals for 2-channel and HT are all that different. Yes, there are differences, but let's face it, most rooms are multi-purpose including dedicated rooms as most folks (the folks reading this thread at least) don't have a dedicated 2-channel room and a dedicated HT).

I disagree that a room with an average 200ms decay time will not sound very dry, however. Maybe "dead" was a bit harsh, but 200ms sounds quite dry and you can't just fix it by adding a ton of diffusers and diffusers, by nature, also absorb and will reduce that further, plus too many diffusers, if not placed surgically and strategically in the room will cause other problems such as interfering with the early reflections you worked so hard to tame, lobing issues depending on the design, etc. If the diffusers are broadband then the room has to be large enough, too. So just placing a ton of diffusers all around a room with a 200ms decay time is NOT an answer IMHO.

As for the rest, we're pretty much on the same page.

I like to target +/- 5db with no EQ - full band. +/- 3db with EQ - full band.

Depending on the size of the room I like to target between 300-500ms and quite honestly will accept 250ms in smaller harder to control rooms and seldom reach much over 400ms in all but the largest of rooms. The target is always 10% but I'll be the first to admit I've yet to achieve it. 20% is more reasonable and I cannot disagree with your 25% recommendation fully, however, I do believe that should be the absolute limit.

With those targets, it's not necessary to state that the bass can decay slower than the specular region other than to say it is common for the lower frequency range to be the hardest to tame and it will take the most skill, time, and budget to get in line without affecting the specular region negatively. Why create two different targets then also state you need to keep the full band decay time within 25% relative?

So again, we may belong to some of the same clubs, pay membership dues to some of the same places, and have similar ideals with but a few differences, but one thing is sure and that is our experience differs by a great amount with you simply having more of it.

I hope we can speak again and would like to get to know you better.

I hope you can at least see that there is room for my philosophy and yours, and that the important thing for folks trying to learn is that they understand the differences, pick a model (yours, mine, or other) and start working towards it to accomplish true audio nirvana!

I hope our paths will cross again sometime, Nyal.

--J

Well Keith, I suppose if 100% of the content you listen to is multi-channel (5 channel or more) and the majority of that content keeps the surrounds active providing that ambiance, then you have a point and I concur that the model which we've been discussing thus far (LEDE/RFZ) is the most suitable and a model approaching NE (Non-Environment) would probably be most suitable.

In this case we'd simply suppress all the reflections to a minimum of -20db from 0ms to infinity without a termination or return.

We'd have an effectively anechoic room at this point and it would not be enjoyable to listen to 2-channel music or even movies that didn't provide ambiance/content in the surrounds, in my opinion.

Your case is a bit different. You actually DO have a dedicated 2 channel room and a dedicated room where you ONLY watch movies.

So... In your case, which I doubt we'll come across very often in this thread, I might recommend just that for you! You won't achieve a true NE room, but you can approach it, which is all we're trying to accomplish in this thread anyway...Getting people on the right path, provide the info and the tools necessary to achieve the goal, but realizing few will take it all the way.

For most folks though, they either don't have a dedicated room at all, in which case it would be pretty boring and lifeless and wouldn't work at all if, for instance, it was a living room where you hoped to have quiet conversation, or they are lucky enough to have ONE dedicated room which must serve a mixture of 2-channel and HT.

When you're listening to two channel and only have those 2 speakers and the room itself to do all the work, in my experience, it's best to account for the needs of those two channels and let the HT fall into place, especially if the ratio of music listening to movie watching approaches 50/50.

This is why there is no one right answer though. Everyone's situation, needs, and goals are different.

This is what makes it difficult if not impossible to put a nice pretty bow on this because we don't start with a neatly wrapped package.

There are different models to get different results and what works for one doesn't work for the other, which is why I hesitate to do what Nyal did and say, This should be your target. Period.

I know he means well, but I just don't believe it can be summed up that easily because of different uses for the rooms and different tastes, not to mention WAF, budget, etc.

So a more one on one approach is probably needed.

There are, however, certain things all the models have in common and only a few of which are drastically different, one of which is this talk about reflections.

Even in the industry there is a wide variance on what is "right" with Floyd Toole himself going against what has been pretty standard for decades now and basically saying there aren't bad reflections and most people prefer them.

While I don't agree, I do agree it's possible that a certain subset of folks that are only used to hearing rooms with lots of reflections and haven't truly experienced a well treated critical listening room might think they want that because they don't know anything else.

There isn't a line in the sand answer here, though, Keith.

What's right for you isn't for the next guy and this was a great question to bring up early on because it shows just how diverse we and our needs truly are.

I'm more than willing to help you achieve whatever model you decide though, to the best of my ability, and as time permits.

To sum it up though, yes, I do believe for you, you need to either decide to try it both ways (depending on how much time/patience you have) or read up on the difference between LEDE and NE and pick one, stop thinking about it, and start working towards it.

Hope this helps,

--J

It's important to see both. Always. You need to know what Audyssey is doing. Unfortunately, there are times where Audyssey makes certain things worse and at times even pushes drivers beyond their limits. We won't know that without both graphs.

Also, once you get into this, who knows, you may find that you no longer need Audyssey, or at least that it doesn't make "as huge of" a difference as it used to, but most likely still "better."

We just don't know enough about your room, your goals, and what you're willing to commit to making it better yet, Keith.

I suspect pretty great things for you and your room though.

I only wish you were close enough for me to meet you and hear it in person, though.

--J