I have finally finished reviewing the 990. All I can say is that I can't believe the difference Processors make on sound. They all sound great and people have their own tastes. I like clear, detail, accurate, and dynamic sound. The Meridian is the reference(for me) for this. IN my humble opinion the 990 sounds just like the Meridian. A liitle brighter but not harsh at all. I would say that this 990 has the best synergy with my Gemstone and speakers to date. Everyone that heard this combo says it is the best in my theater room so far. Very open sound. I love it. I will be keeping the 990. It has that wow factor that I have been missing since the meridian. I would call it the $1000 Meridian. There is no need to upgrade anymore. For those that think this processor is good but not as good as expensive processors then they are being fooled by the price. When I was evaluating it I was actually waiting for something bad. It never happened. I have owned ADA, Lexicon, Krell, Mcintosh, Meridian, Emotiva, and have heard anthem and parasound with my Speakers. The 990 is right next to the Meridian followed by the MAC, Krell and ADA. It mates well with my amp. Synergy is key. My speakers are M&K S-5000 THX(7 of them). I use a SVS PB12/PLUS/2 subwoofer. I am still amazed. I have read that people like the anthem better but it is taste, not because it is better. Same goes for the Emotiva.

I'm thrilled to hear that you've found what you were looking for! It's all the more impressive in light of how challenging a task you had set before yourself (finding a substitute for the Meridian 861 that sacrificed as little as possible). It's also cool to hear such a complement paid to the 990.

I was not expecting it to be this good. It sounds just like the meridian with a little more brightness. I actually like that difference. My dog ears guy looked at me and said IT's back, meaning the sound of the meridian is back. He could not believe it either. What was even better is that I set all the crossovers to 80 with small speakers and let it auto calibrate and this is the result. Excellent job. I am still amazed. I will stick with this until hdmi and dolby true hd becomes more widespread.

MK,

So glad to see your review finally!

I'm also very glad to see you're enjoying the 990. I've so far found it to be a very good pre-pro myself.

I'm hoping Outlaw will debut a next generation pre-pro that will include HDMI 1.3 video AND audio capabilities sometime next year. I'm keeping my 990 shipping box and packaging materials so that I can sell my 990 whenever this occurs.

Again, excellent review!

Let's not kid ourselves. Much of what you're paying for when you buy a Meridian processor is their intellectual property and modular construction. Their proprietary surround processing and room correction technologies are not available elsewhere, at any price (let alone $1000).

It's always nice to fantasize that you're getting champagne at beer prices, but that's not the case here. No slight against the 990, but Outlaw isn't going to catch up overnight to Meridian's three decades of research in digital audio, surround processing and room correction technologies. The best you can hope for is off-the-shelf stuff, licensed from companies like Dolby and DTS.

Outlaw's strength is in the value offered. You get a feature-rich stand alone pre-pro with excellent sound quality at a price that few manufacturers can touch. But that's very different from what Meridian is offering, both philosophically and practically. The 990 is no more a "$1000 Meridian" than the 861 is a $20,000 Outlaw.

I disagree. The Meridian is better, no doubt. But for watching movies or TV they sound very similar. Music I think the meridian is better due to trifield. I have owned many high end processors. The outlaw hangs with them for movie watching. It has all the clarity and detail. Some lacked the clarity that the outlaw has. The meridian sounds just like the outlaw, just a tad smoother on the upper end. For my purposes(home theater and high definition TV) the outlaw is awesome. Of course you have to like clarity, detail, and dynamic sound. If you like warm, then the outlaw is aweful. This is just not my opinion as well. Trust me, I was looking for something bad compared to the meridian. It did not happen. I have a circle of friends that come over all the time to watch movies. They have know idea I swap out gear. But when they say WOW, what did you do, I know something is good. It happened with the meridian and the outlaw. Don't get me wrong, i love the meridian and when I say $1000 Meridian I mean how it sounds. I know the meridian can do alot more and is upgradeable. I know they make their own dsp's, but for 7.1 movie watching it is close. Very close. I don't like warm sounding equipment, that is just me. I have owned the meridian 568 and the meridian 861, are they that much different in sound quality, no. Can I hear the difference, yes. The 861 has more clarity on every level. The outlaw is better than the 568, at least with my equipment. If I matched the 861 with their speakers and dvd player will it be even better, no doubt. I was looking for a processor that could match the 861 sonics as close as possible with my equipment and the outlaw is damn close. If I had a $10000 pair of speakers maybe that would change but not with my $3000 a pair. I am not kidding myself at all.

Whether you're listening in a movie theatre or at symphony hall, more than half the sound reaching your ears comes from the room and not from the speakers or performers. The same holds true when listening at home; you hear more from the room than you do from your speakers.

The dimensions of your room will cause some low frequencies to bounce back and forth between walls for much longer than other frequencies. This is the major reason for the "one-noted bass" sound. The long decay times also tend to obscure details that immediately follow.

The Meridian pre-pro can minimize the decay time for these problematic frequencies and cut down on the ringing. Since we're dealing with low frequencies, the wavelengths are large enough for the benefits to be heard at multiple seats.

With the lingering notes tamed, sounds that were normally obscured by the overhanging sounds are now unmasked, allowing you to hear everything more clearly across the entire frequency range. This is especially noticable with dialogue in movie soundtracks and TV programs.

You get to hear less of the room's unwanted contributions, and hear more of what your speakers actually sound like and more of what's on the recording. Always a good thing, irrespective of movies or music. And you don't need $10K speakers to hear the improvement.

How does the 990 address room resonances?

All that is true. I don't disagree. My Meridian was not a version 4.2 with room correction although it could have been upgraded. I am not talking version 4.2 vs 990. I am talking version 2.81. So the only way to fix any problems with the room is with room treatments which have been done. Is my room perfect, no, but it sounds pretty good. So in the area of build quality, upgradeability, looks, name, the Meridian is much, much better. No question. But for simple dts, dd, 7.1 with my equipment the 990 is at least 95% of the meridian. That is all.

mktheater:

First, thanks for taking the time to compare and contrast the various SSPs. The information is most helpful to us Outlaws!

Second, in the surround sound processing realm, aren't the 970 and 990 essentially the same? The reason I ask is that I am quite happy with my 970, but if your conclusions about the 990's movie performance apply to both units, it makes me even more pleased with my purchase (And, like you, will stave off my usual case of upgrade-itis! At least for the foreseeable future)

Third, with all due respect to sdurani's comments about room equalization, I do not find that a compelling reason in its own right to justify the price differences between the two units. I could be missing something about the purity of the Meridan's room correction circuitry, but the whole concept seems at odds with conventioanl wisdom: i.e., that that degree of signal manipulation, at least with repsect to mid- and high-frequency information, is anathema to preserving the fidelity of the input signal. With that in mind, I was always told the way to attack room problems is with acoutical treatments, or in the case of bass inaccuracies, a product such as the SMS-1. Neither of which puts you at risk of mucking up the critical mid range and higher frequencies, imaging, tonal balance, etc.
Lastly, any issues with the 990's tendency to be more neutral than warm can easily be addressed with careful choices in assoicated electronics, interconnects and speaker cables. So I do not consider this a drawback in the least.

Thanks again for the review.

The 990 and 970 are completely different platforms, actually. The 990 is based on the Sherwood (Etronics) P-965 with software and hardware revisions to add several features. The 970 is a processor version of the 1070, which was developed from the ground up by Outlaw.

Sdurani makes some good points. Room correction and equalization can be a very difficult thing to do properly and an easy thing to mess up, but Meridian and Lexicon (which I'll include since Sanjay happens to use a Lex) have both done some pretty unusual amount of research and development on things like this. Even moreso than the hardware involved, the engineering, programming, and research involved in doing what the latest versions of Meridian and Lexicon processors do is very costly, and you simply can't get it without moving to the five-figure price bracket. Outlaw can't do it, and neither can Rotel, Adcom, Anthem, Emotiva, or the other usual suspects.

On the other hand, mktheater makes some interesting points about how the 990 compares to his older version Meridian 861 when it comes to a few of the core design features. Any surround processor should strive to do standard surround decoding (Dolby Digital, DTS, Pro Logic IIx), D/A conversion, and analog output well. If the 990 can get close to the Meridian in these regards, then kudos to the 990.

Gonk,
I thought the 990 and 970 both used a cs-49400 crystal processor. If thats the case wouldn't the 970 sound just like the 990?

The 990 and 970 both use the 49400, but there are a lot of receivers and processors that use the 49400. That's just one piece of the puzzle. Other important factors are the DAC's (which will probably have even more impact on the sound than the DSP engine) and analog section design. The 990 uses an Analog Device AD1852 24-bit/192kHz DAC, which is a better (and more expensive) chip than the Cirrus CS42528 (also 24-bit/192kHz) DAC chip in the 970.

To the extent that I understand where the DACs sonic signature comes into play with surround sound playback for movies -- which is not at all , I recall that when I talked to Outlaw about the 970 vs. 990, I was told movie performance would be the same between the two units.

As to where I understood the 990 really differed from the 970 was:
- Better DAC and upsampling for digital/CD playback
- Balanced outputs
- Phono stage
- More functionality in terms of set up and switching.

Taking into account how I use my pre/pro, I assumed I would get little if any benefit by upgrading to the 990. My playback habits involve using digital processing for movies and analog bypass for everything else. I don't listen to SACD and do not like surround sound processing applied to stereo. I also do not have balanced inputs on my amps and have an outboard, tube phono stage. Lastly, the additional video switching, auto setup, etc. did not add any value for me, so I opted for the 970.

I may be wrong about my assumptions and subsequent choice, so if I'm missed the boat on how the 990 can or cannot outperform the 970 for my system needs, please chime in.

I feel the analogue section is the most important part because everything gets converted to analogue(all speakers are analogue). If you read you will notice that most of the best sounding processors have great analogue sections. Since my review I have watched a couple of movies. I have still said that the Meridian has a little smoother high end. That means it is not as in your face. Most people like the sound of the 990 better. Everyone is saying how much better they like the in your face presentation. I like it as well. Some movies get a little bright but others sound better like the matrix, I have never heard these movies sound this good before, and I have owned many expensive processors. Trust me, If the 990 was anything like the Emotiva(warm sounding) I would have returned it and tried something different. The 990 has all the detail of the meridian, actually you can hear more in the surrounds with the 990. BY the way, the auto calibration had my system 13-14 db's too high. It made my reference level -15 db's. I manually calibrated it but have not tried it at reference with my demos. I will use the auto again if I don't like the results as much. I just can't leave well enough alone. You guys have to hear this with the gemstone amp and the M&K speakers at reference levels. real

Don't get me wrong, Videodrome - the 970 is by all accounts a nice, solid performer. I don't know how the analog section compares to the 990's, but I suspect the differences would be subtle in analog bypass mode. I've also seen similar comments to those you've heard, suggesting that the differences between the 970 and 990 would be most noticeable with digital input and music playback (which is where I noticed the biggest difference when moving from a Model 950 to the 990) and that movie performance would be more comparable. I don't think that you made a bad choice going with the 970.

MRC (Meridian Room Correction) doesn't touch mid- and high-frequency information. All of the correction is done below 250Hz, where the wavelengths are large enough to benefit multiple listening seats.

Conventional wisdom would have you believe that maintaining signal purity through the playback hardware allows you to hear what's in the recording itself. Nothing could be further from the truth. When you listen to your system, more than 50% of what you're hearing is the room, not your speakers.

Your room is an audio processor, whether you like it or not. If you want to really hear what's on the recording and what your speakers actually sound like, then you have to minimize the room's unwanted contributions to the overall sound. Otherwise, the majority of what you're hearing is neither the recording nor your speakers. That's not my idea of "purity". How do you target a piece of rigid fiberglass to to address a room resonance at 41.5Hz specifically? How do you stop absorbers or diffusers from touching the mid and high frequencies that you want left alone?

Gotcha. I guess I'm trying a round about way of rationalizing: if the 990 is 95% of the Meridian 861, and my 970 -- at least on movies -- is 85% of the 990, then my 970 is 80% of the Meridian.

My bad on the extent of the 861's equalization. I am not that familar with the unit. That said, I think the better option is to buy a 990 and an SMS-1. Then put the $10,000 savings toward other equipment or a dedicated listening room.

It's an option, but it can't come close to what the Meridian does. The SMS-1 measures in the amplitude domain, looking for low frequencies that are louder or softer than average. Since bass levels vary at different seats, fixing a peak or dip in one seat can make that same sound worse in other seats.

MRC measures in the time domain, looking for low frequencies that take longer than average to decay. Since these frequencies are problematic because they bounce back and forth between the walls for too long, any listener seated between those walls will hear the ringing. Fixing this problem in one seat will yield beneficial results in other seats.

That a big difference.

Above roughly 300Hz, room resonances are too close together to do decent correction electronically. However, below that, wavelengths are large enough to be able to pick out probematic frequencies and address them individually. Since the SMS-1 only works on the sub, low frequency problems (below 300Hz) in the main channels will go unaddressed. Since MRC corrects all 7.1 channels, it catches low frequency ringing whether they're in the subwoofer or main channels.

That's another big difference.

Finally, if you look into psychoacoustics, you'll find that our human hearing tends to notice and prefer when time based problems are corrected rather than amplitude based problems (which our ear/brain mechanism is more tolerant of).

Also an important difference.

While the SMS-1 can be useful for trying to flatten out the frequency response of your sub, it shouldn't be confused with what Meridian does. Why do you even care about the Meridian? The 990 and 970 represent two of the best values being offered in home audio today. Can't you guys simply enjoy them for what they are instead of trying to pretend they're something that they clearly aren't? Is that so unreasonable?

Agreed. Attention to detail in getting the analog stage 'just right' is what separates a good DAC from a great one. Another important factor is immunity from jitter.

At the end of the day, ranking products based on their performance is a slippery slope - it's too dependent on the individual user's tastes, associated equipment, and too many other inconsistent factors. That's why I created my SSP chart back in 2002 - it can't compare sound quality or other factors because those factors cannot be tabulated fairly, but it can compare simple features.
As much as a piece of my ego might enjoy the notion that my 990 does X% of what a product (Meridian, Lexicon, or whatever) costing an order of magnitude more, the reality is that in general Sanjay is right. (I say "in general" because there will be a few cases such as mktheater's when someone actually does compare units at this wide a price range.) We can try to assign values, but in the end it's a pretty fruitless exercise because the values will be different for each person.

I think this thread has morphed from a comparison of the Meridian Version 2.81 vs. the 990 to a larger debate that includes other products and our various comfort levels that we got what we wanted for the money invested.

Sanjay, I can only conclude from your comments that you have had the benefit of the 861 Version 2.81, Version 4.2 and the 990 all in you system to compare and contrast. I have not, and unfortunately, such comparisons are above my paygrade

However, I do feel MKTheater's thorough audition of the Meridian 2.81 and 990 provided a good insight into the relative sterngths and weaknesses of both units. If I had been privy to the audtion, maybe I would have come to the same conclusion; maybe not. But MKTheater's findings do comport with my own experience that significantly larger expenditures on gear often yield incremental improvements.

With that, I wish everyone a great weekend and hope you have a chance to sit down, fire up your system, and enjoy a great movie.

I have more to add. The most realistic system I ever had was my Mcintosh and Klipsch system. The sound effects were so real that when someone knocked on a door some of friends would get up to answer the door, then they would realize it was the movie. Same goes for cell phones and such. Then I came across my favorite theater speaker and had to have them. I liked them better than my Klipsch THX ultra 2(these were great). They had better highs. The only problem was that I lost that real sound. So I was on my quest to find it with these speakers. Guess what guys, I did with the 990, Gemstone amp, and my M&K S-5000 thx speakers. Once again people are getting up to answer the door. It fooled me one time as well. Very accurate. I am liking this better than the Meridian for movies. The Meridian never did this.

- We've tried to answer some doorbells and knocks on the door over the years, and we also had a case where my father-in-law walked in the back door and said "hi" while we were watching a movie and we thought it was the movie.

You would be suprised how many pieces of equipment (high end) don't do this. To me a theater should sound life like, real. I know it is easy to fool the guys that never heard 7.1 or 5.1 before but when I get fooled then we are on to something. I have been at this for 11 years and started with a receiver, klh speakers, and a laser disc player. I found a high end store and told myself that is what I like. Well, I have exceeded those expectations. I think many audiophiles like a warm or a laid back presentaion which may be good for music but I never liked it for theater. I think this is why many never consider the 990 for their processor because it does not present that type of sound. I have tried going the great musical home theater(equipment and speakers known to produce great music) route but it always failed me for theater. You know people say that a great piece of equipment that can do music right can easily do hometheater, I disagree. Been there, done that. I did not like it. When I started putting together a pure theater(equipment built for theater) then it came together. The music happen to be good too, but then again my speakers were meant for theater. I know people might say why didn't you stick with the Mac system, I will say changing that system to this one I get better results(slight) and with the extra money I bought 6 theater seats. Gonk what speakers are you using? I am assuming that you use outlaw pre and amp.

mktheater,

I too have been very impressed with the 990 and Klipsch combination. When I set out to convert my garage into a home theater (project took longer than I care to remember) I auditioned many speaker systems but absolutely fell in love with the Klipschorns and essentially designed the room for them. By pure luck run across a very favorable review in a home theater magazine about Outlaw Audio and the Model 990. Ended up with the 990/7125 LFM-1 combo.
The realism is incredible. Everything from movies to my sons Xbox 360 gaming seems to come to life.

I've got an Outlaw 990 and Outlaw amps (7500 and a pair of M200's), Outlaw LFM-1 sub with SMS-1, and Paradigm Reference (Studio 60v2 mains, Studio CCv2 center, Studio ADPv2 back surrounds) with some Axiom M3's for side surrounds due to some mounting limitations on my side walls.

I did not use the 990 with Klipsch. I used Mcintosh with it. Everyone who has watched a movie recently has said it sounds better than ever. Most reactions are Wow, did you change something. Yes, I swapped out a $15000 piece of gear for a $1100 one. HAHA. Don't get me wrong I love the Meridian. I just don't agree with the people that say the 990 is a great bang for the buck, It is a great processor period. Just because the Meridian was so expensive does not mean it is that much better in sound quality.

Dr. megalito,
What klipsch speakers are you running?

He said in his post that he is running Klipschorns.

bwallen77,

Heritage series Klipsch for mains and center (Klipschorns L&R, Belle for center) RS-7 for rear and sides and of course the Outlaw LFM-1 sub.

Deleted duplicate post.

mktheater,
It's a safe bet we have different tastes in sound, but I've enjoyed reading your posts. I've always listened to music more critically, as I finally just got a big screen earlier this year. For music I prefer a warmer sound, which led me to purchase a set of Rocket speakers that I really like. However, I'm driving them with a 1999 vintage Onkyo box that I got from Circuit City for about $500 - it's actually not bad, but that's where my next upgrade will be.

Rocket folks typically like Emo gear, which also has a warm sound as you've noticed. I'm wondering if it might not be a bad idea to pair warm speakers with more bright sounding electronics? I would like more of that "you are there" effect for movies, but not if my tunes get too hissy. I've never heard Outlaw gear, but I did get to hear an Arcam AVP700/P1000 a few months back and really like that. Guess I'm curious if warm speakers and brighter electronics go together like peanut butter and jelly or oil and water.

With regard to the compatibility of a two-channel system with a home theater system, I would agree with mktheater that, in many respects, they work at cross purposes.

I think there are products out there that can bridge the gap. I consider my 970 one of those, largely because of the bypass mode it offers.

In would also include my speakers. I really struggled to find a replacement for my Snell CIII's and was resigned to buying a home theater oriented product that, at best, would not do anything offensive on two channel listening. I was glad to stumble across the 11Ls as they got rave reviews for two channel systems, plus had the added benefit of being part of a larger HT product line that includes a matching center, satelittes and a sub.

While the system probably does not have the dynamic impact of the Klipsch's, the fact the speakers are designed to work together has given me a common sonic signature across my mains and center (I plan to add the surrounds later) which helps add that seamless, 360 degree effect that makes HT sound more lifelike.

Anyway, I have been VERY happy with them and once I get my SMS-1 and the satelittes, I think the system is really going to come together.

ComradeX,
I don't feel there is a best processor, just a best sytem that matches your speakers. The speakers you choose will have the biggest impact on the sound then the electronics to bring out that sound. The emotiva was a very good processor but just did not match with my gear. You like the sound of your speakers so now you have to find electronics that will let that sound thru without any alteration. I don't think onkyo is warm sounding, is it? I always felt that the integra stuff was great with M&K speakers, actually it would be my pick for receivers(never heard the outlaw)or the B&K. The best bet is to try gear and hear for your self. Emo gear and outlaw gear you can return. Actually I am interested in trying the new Nuforce processor. Anyone try this? BTW I always felt that good 2 channel does not mean good hometheater and vice versa. I tried a very musical sytem for movies and it just lacked that WOW factor. It's sound was good, very good but I could always do better with theater only gear. I guess I am glad that I don't listen to 2 channel, it makes it much easier. Of course I am talking about trying to get the best of both worlds which is almost impossible. I believe in separate 2 channel and theater. I also think the 990 sounds really good for music. The Meridian was much better though.

Just a couple of two-centers:
ComradeX, saying that two things go together "like oil and water" is saying they DON'T mix at all, just as oil and water don't mix.
MKtheater apparently believes 2 channel and theater do mix like oil and water. Unfortunately those of us who do listen to two channel (sometimes called "music") more often than home theater, and don't have as much money as some others apparently do, simply can't afford to hold such beliefs. Sorry about that.

IMHO, I think you hit the nail on the head. For most of us, it's a question of what compromise we're willing to accept in terms of performance. My system is designed around what is important to me sonically and what I'm willing to trade off either because (1) I can't afford it; or (2) it would look really crappy in my game room / HT room and my wife would divorce my a$$.

But if cost were no object and I had beaucoup room to play with, I have no doubt a pair of Wilson Audio MAXX speakers would absolutely, positively rock on both movies and 2-channel. Similarly, electronics up to par with that sort of loudspeaker would excel at whatever signal you threw at them. In my mind, the best of both worlds would involve having a great processor (like the 990 ) and a preamp that has a surround sound pass-thru, e.g. the McCormack RLD-1.

So bottom line is, I think you can get the best of both worlds... if you're willing to spend the money!

Don't get me wrong, I think the 990 does music quite well. Great clarity. I just think you can keep 2 channel music and theater seperate and get better results and not spend alot of money. People think you have to spend $1000's to get one system to do both great and I believe you can spend less to get better results

Don't get me wrong, I think the 990 does music quite well. Great clarity. I just think you can keep 2 channel music and theater seperate and get better results and not spend alot of money. People think you have to spend $1000's to get one system to do both great and I believe you can spend less to get better results

All good points there. Even if I had the budget for two quality systems, I do all my watching and listening in the same room anyway, so I need one that can handle both. I've never heard my speakers with anything other than my Onkyo - it would be really interesting to try some different ones. Guess if you can sync things up with some different internet companies so you can try some different things side by side, you could tell a lot.

I started my upgrades with speakers, since I believe they make the biggest impact in the sound you hear. Given that I went with a warmer, "musical" sound, I'm concerned about getting an amp and pre/pro that are also "warm". My thought is if the detail is there, the speakers will color things the way I like, but I dont want to miss anything. On the other hand, I understand that some things match well and some dont. Guess you pretty much just have to try them out.

I might be trying the Nuforce processor as well. I am just curious. I am liking the outlaw better everyday. Sometimes I think it might get a little bright but it never hurts my ears. Usually when it is bright it hurts your ears. I think the outlaw has a up front soundstage with alot of detail, but not necessarily bright. To put things into perspective I owned so called warm equipment(Mcintosh) and it had the same characteristics as my 990. That is what speakers will do because they were Klipsch and now I have M&K.

I like my 990 for home theater (I have a separate system for stereo) but do find it a little on the bright side - and my speakers are anything but bright. What I did was turn "Theater Compensation" on which helped a lot.

Will

I am now using the 7.1 direct with my HD dvd player and it sounds better than anything I have ever used. Great stuff.

Sanjay,

Long time, no read.

Help me out here...exactly what does the Meridian Room Correction do that any digital PEQ doesn't do?

Never mind how one arrives at what they intend to do to the input signal, exactly what does MRC do with notch filters to the input signal that differs from employing any other PEQ?

Bosso

Bosso,

The digital PEQ itself is simply the device/tool used to apply filters to the signal. Automated room correction systems are more than a parametric equalizer. They have to measure what the room is adding to the overall sound and then decide which problems to address, how to deal with those with and then calculate the filters needed to ameliorate the problems.

Dismissing "how one arrives at what they intended to do to the input signal" and asking only about the notch filters is akin to asking what Rodin did with a chisel that other sculptors didn't. He hit it with a hammer, just like others did, and he chiped away at marble, just like other sculptors did. But that doesn't explain why he ended up sculpting something as enduring as The Thinker while his contemporaries didn't. The same tool will give different results depending on what you do with it.

To that end, MRC is different from most automated room correction systems (many of which also use a digital PEQ) in how it measures and what it chooses to correct. As mentioned in my post you quoted, most EQ systems measure amplitude and try to flatten out frequency response. By comparison, MRC measures in the time domain, looking specifically for frequencies that have long decay times, dialing them down to the average RT60 for the frequency range it is trying to correct.

So the difference between auto-EQ systems is not how they use their filters but what problems they use their filters for. For example: if your speaker had an amplitude peak at 55Hz, most auto-EQ systems (like the SMS-1) will use their filters try to bring it down so that it is flat. MRC won't touch it. Meridian explicitly states that flat frequency response is not the goal of MRC.

For a more detailed explanation (from the horse's mouth), check out Meridian's white paper on room correction here .

The paper references an AES presentation (The Loudspeaker-Room Interface - Controlling Excitation of Room Modes, Rhonda J. Wilson, Michael D. Capp, and J. Robert Stuart, Meridian Audio, AES 23rd Int'l Conference, Copenhagen, 2003) described here . This research was the basis for Meridian Room Correction.

If you find the description intriguing, you can purchase the paper from AES.

Sanjay,

Yes, I'm familiar with the paper you linked to, and have read it when it was originally published. I must tell you that it reads much more like a marketing blurb than a white paper. Let's examine some key points...

1. The paper attempts to mislead by first mentioning that 'room equalisation' is accomplished by using a pink noise source. This is so that the impulse response used to generate the same FR graph can be differentiated as unique to MRC later on in the paper, IMO.

2. The mention of some pro sound people using a graphic equalizer to create an inverse curve in the input signal is simply the same ploy, as no one uses a graphic EQ to equalize a HT and most savvy folks know that PEQ can't 'fix' a room.

3. They say that inverse curve equalization is wrong because it:
a. 'aims to arrive at a flat response which will suck the life out of a room.'
b. 'a graphic EQ [an analog EQ] produces all kinds of undesirable effects...ringing and phase errors.' Still, they correctly mention here that 'DSP-modelled EQ [which everyone uses] can be designed to avoid these problems.'
c. And that using an analog graphic EQ makes it 'problematical to try to perfect a room's impulse response'.

4. Next, they mention that to cancel out a 10dB notch [in FR] requires 10 times the power, causing one to run out of amplifier power. This sort of info is certainly for the uninitiated.

5. They then admit that 'Indeed, EQ like this [inverse curve PEQ] only really works for one listening position.'

So, first they spend 2 pages telling us why room equalization doesn't work, then they casually admit that it works for the primary LP.

6. They go on to say that looking at room modes is a better approach. Well, if it ignores a 'peak at 50Hz', whether it's just a poorly designed subwoofer or a boundary gain issue, I wonder how it can be thought of as better?

7. We now discuss that MRC only concerns itself with low frequencies, again PEQ 101 for those who employ one.

8. Next, under 'Filtering and Resonance', we finally get to the fact that MRC is a parametric equalizer that identifies peaks and flattens them to a less peaky state:
'So the aim of our room correction system is to identify important low frequency room modes-and their Q- and construct notch filters to reduce excessive decay times due to resonance at those frequencies to something more like the overall decay time of the room.'

9. Now we read that the range is 15Hz-250Hz. What is the range of the SMS-1?

To keep this shorter than it will otherwise be, I'll just say that MRC is nothing more than a PEQ that uses measurements from multiple spots in the HT, then averages them into a single FR graph, which it smoothes and then fashions PEQ notch filters to attack the peaks from 15-250 Hz.

It doesn't address placement (room and boundary gain induced peaks), delay settings and variable phase control of the sub to realign phase (which also can correct peaks and dips), and it describes that it's designed to treat the average sized HT and to treat it such as to reduce it to below the average reverberation time.

As they admit in the paper: "Here it is important to understand that there is a 1 to 1 relationship between frequency domain and time domain, i.e. time domain does not include any additional information not already present in frequency domain."

They offer impulse response, frequency response and waterfall graphs, all of which are derived from the impulse response (clicks or chirps).

It's redeeming quality, IMHO is that it treats all channels, but 'white papers' that contain words like 'astonishing level of DSP capability' leave me wondering if I'm being educated or sold.

It seems to be the latest gadget for the upscale owner who typically throws the manual away and wants to push a button for setup, IMO.

Certainly the same tool gives different results depending on what you do with it, but, as your own illustration points out, a capable sculptor like Rodin will create a better result than the same tool driven by a computer program.

Bosso

A wee point of fact irrelevant to this discussion and to audio but I'm too picky to let it go by: Sdurani and Bossobass have both mentioned Rodin's work with a chisel. Rodin actually didn't use a chisel. Hr worked in clay, believe it or not - see Wikipedia. After he finished a figure it was then cast in bronze or chiseled in marble, not by him but by his large corps of assistants. Sdurani, you should have said Michelangelo.

While we're coming up with nitpicky art remarks (and while the debate moves beyong my experience with EQ), I'll add my own.
I read this and was reminded of a brass box that dad picked up while at a metalsmithing event in Carbondale a month or so ago - milled out by a CNC machine, but using instructions created by Richard Maudsley. Maudsley's always been know for deeply intricate, detailed designs (often using thousands of tiny pieces of tubing that he would draw through custom-made draw plates to create unique shapes, cut into lengths, and solder together). I ought to get a picture of that puppy for you guys. If Rodin was giving the computer program its instructions, the program would become the tool. (Granted, I'm twisting bosso's point all into knots for no good reason - the statement is quite true if there isn't that talent somewhere upstream - but it was funny to see the idea right after seeing Maudsley's CNC brass box.)

Hey, this isn't audio but it's fun! Merry Christmas, everyone.

As for the subject at hand, I think that sdurani and bossobass (both pretty darn knowledgeable fellows) have hit on an underlying aspect of room equalization: there is no one absolute, agreed-upon answer. We know that our rooms do things to the sound that alter what our ears hear, but how to compensate for it is a tough nut to crack. All the more reason to kick the tires on the more common approaches to see what turns up...

Sorry for the delayed response; shopping and all. What difference does that make? The style of the writing is not important; it's the content that matters. If Meridian is presenting lies as facts, point them out. That's a complaint? Is there a reason why basic concepts should not be explained in that paper? "Admit"? You make it sound like they were grudgingly forced to concede something there were trying to hide from readers. Hardly. They describe the limitation of using an inverse curve in order to explain why that technique isn't employed for their automatic room correction. They have no interest in a correction system that results in improvements at only one listening location. Because they're trying to address unwanted contributions from the room, not the voicing of a speaker. A bump at 50Hz can be the result of deliberate speaker design or caused by boundry gain. That's why they don't correct it. It would be like full-range room correction that compensated for a treble roll-off designed into a particular speaker. If I bought a speaker specifically for its warm sound, I wouldn't want that sound to be "corrected". Better instead to deal with what they know the room is adding (e.g., reverberation) instead of something that may be part of the speaker design. Again, this isn't something that Merdian was trying to hide from readers. They've been very clear about what their room correction system does: address long decay times for frequencies below 250Hz. They've never pretended otherwise. Not all peaks. That's what differentiates it from many other automatic room correction systems. The SMS-1 has an operating range of 15Hz-200Hz, but for a single channel only. Since low frequencies (and their associated problems) aren't limited to the just the subwoofer, MRC is applied to all channels. It doesn't average the samples because a peak and a dip can cancel each other out when added, giving the impression that there isn't a problem when in fact there are two problems. None of the better automatic room correction systems (Audyssey, H/K, Lexicon, Meridian) use averaging when correlating data from different listening locations. MRC also doesn't attack every peak under 250Hz, only ones with long reverberation times. Wow, you say that like it's a bad thing. Would that every electronic device were designed with such a goal in mind. Oh that wasn't what my illustration pointed out. I was comparing Rodin to other sculptors, not some automated sculpting device. The point being that few individuals amongst their contemporaries are capable of creating better results using the same tool. But let's use your version of the analogy and try to create better results than a computer program (i.e., let's take the "automatic" out of automatic room correction).

Help me out here...exactly how does they typical SMS-1 owner become the Rodin of electronic room correction and digital PEQ programming?

Never mind what a digital PEQ may be capable of, exactly how do us consumers amass the knowledge needed to take proper measurements, build appropriate filters and apply them; all in a way that results in improvements at more than one single listening location?

Meanwhile, Happy Holidays to you and your's.

Thanx for the correction about Rodin. I'll keep Michelangelo in mind next time.

Merry Christmas.

That's the point behind the automatic room correction systems. The better ones were designed by people that are some of the most knowledgeable in the field of acousitics. The goal isn't perfection, just better results than the typical consumer would get on their own using a digital parametric equalizer.

Actually, the SMS-1 goes from either 5Hz or 15Hz (depending on the firmware version) to 120Hz - the display goes to 200Hz, but the EQ's can't operate above 120.

I know this thread is dead, but I have to say that was the most ridiculous over the top comparison I have ever read.

This is to mktheater, I personally have heard the Meridian 861 and the Outlaw audio 990, and there is no way in heck you can possibly compare the meridian to either of these two. You sound like you work for Outlaw audio and are part of the marketing team because I blind tested this thing with 12 other people in the room and the 990 didn't even compare. The meridian was several cuts above. You're comparing a $20k preamp to a sub $2k preamp. I know this is all subjective, but one can definitely tell when a preamp sounds monumentally better than another. Its like saying a stock Subaru WRX STi blew away a bugatti Veron in a drag race with 2 competent drivers.Even at its basic settings it blew away the 990. We tested it on different types of apeakers, using Magenpan, Paradigm, and Mirage OMD. Then after 4-5 hours of setting it up with a professional which is what its made for, because there a MANY MANY different options for customizing the sound it further smoked the 990. I would say the 990 is the best $7.5k value wise. But to compare it to a meridian is just downright ridiculous.