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Revel F208?

andreasmaaan

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Room mode calculators like that Amroc one are based on the (almost never correct) assumption that your walls are 100% reflective of bass frequencies. Given your room situation, I'd say there's little to no use in trying to use them to work out what/where your room modes are going to be (I'm not familiar with the REW one - perhaps it's a lot more sophisticated).

However, setting up a speakers/subs and measuring will be useful, making adjustments (to speaker/sub position and/or with EQ if available) until you get the bass about right at the listening position(s). Getting a second sub and not spending as much on as large a pair of speakers might be an equally good option IMHO.

Big speaker sound tends to result from (1) having a system that is capable of high SPLs and low bass without significant distortion and (2) the physical size of the speaker, which tends to result in (a) narrower dispersion in the midrange and (b) less interaction between the direct sound and the sound reflected off the front wall.

(1) can be achieved with smaller mains + sub(s), while (2) requires either physically large mains or (in theory at least) some form of cardioid directivity control, a la D&D 8C or Kii Three. In general, two subs is better than one when it comes to smoother in-room bass response.
 
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mitchco

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@andreasmaaan re: "Room mode calculators like that Amroc one are based on the (almost never correct) assumption that your walls are 100% reflective of bass frequencies." Can you point to where it says this about the calculator?

My point is because the calculator also outputs sound, @stunta can spend 5 minutes centring on the room modes that excite the pressure zone he is sitting in and can stand up and walk out of it to hear the difference. Dead simple and takes 5 minutes or less. And highly educational to hear what it sounds like.

No, it is not a full on accurate simulator but more accurate than most people would believe especially when you hear the modes line up just about perfect with the calculator. This isn't rocket science and we don't need full on FEM analysis either. https://amcoustics.com/articles/roommodes
 

Ron Texas

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I suggest that you try them without the sub(s) since (1) you want "big" sounding speakers and this is the way to hear if they are and (2) it might be difficult to optimize the bass management in the short term of the loan. Otherwise, go for it.
I concur with adding bass management is not impossible, but it's very difficult.
 

andreasmaaan

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@mitchco it doesn’t say it anywhere to my knowledge, but all standard formulas for such calculations assume this. They also assume no doorways, windows or other openings. Are you saying that the Amroc calculator makes assumptions about surface absorption/reflection coefficients and other irregularities and incorporates these? If so, where does it say this? And what are the assumptions and how accurate are they in respect of the OP’s room?
 
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DonH56

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The fact that the surfaces are not 100% reflective, perfectly rigid panels does not significantly affect the modes' frequency, just their depth (or peaks).

None of the calculators does a great job with asymmetric rooms (anything other than a rectangular shape) and generally do not take into account openings like open doors, windows, or a room open to the rest of the house. It can still be useful because local nulls and peaks can still be found, e.g. if one side is open to the house, the back-to-front and floor-to-ceiling modes still apply. IME they do a decent job with closed doors and windows (opening them changes things, natch) with again the caveat that the amplitudes shift somewhat and so they may not be perfectly accurate. My room has a slanted wall (concesion to aesthetics to the big open areas on the other side of the wall) , a dropped ceiling on one side for ducts, and big window wells that muck with the room calculators but they are still close enough to figure out the causes of the main modes in the room.

Getting it right requires COMSOL (a simulator that can handle flow studies) or something like it, and despite being a beta tester ages ago, I do not currently have COMSOL installed and probably couldn't use it if I did. ;)

YMMV - Don
 
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stunta

stunta

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It sounds like my focus should be on room acoustics first. This thread has surely taken a turn from the speakers to the room which is great. Perhaps I should wait and sort these things out before going for new speakers. I might have to wait anyway since a pipe leak has delayed the rest of the work in the basement. I now a gaping hole in the ceiling of this room where pipe sections were replaced.

Meanwhile, I'll pull my old speakers out (ATC SCM19 v1) and set them up first. The REL subwoofer is still in a box from the move, so once I manage to bring that into the room (might take a week or so), I can take some initial measurements.

@mitchco: amroc is very cool. Probably too cool for novices like me. Thanks.

@DonH56: Interestingly, I sent an email a couple of days ago to my contractor asking him about rockwool as an option for insulation; specifically this.

There is some debate about the room simulator tools. I feel like they are at the very least a good place to start before taking measurements. If the measurements show high variance with the simulator, its a good indicator that something is off.

I like the idea of a rolling chair I can place in front of the seating area for serious listening. For movies and Netflix, I am not that picky as long as the voices are clear and the explosions are well, explosive :)

As for the Revel F208s, the wife is dead against it - she thinks they will be an incremental upgrade and I will want to get active speakers eventually thus spending a lot more in the end. She is probably right so I have some pondering to do.
 

Ron Party

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If you put a bar in that room, speaker placement and room acoustics won't matter as much... just sayin':)
 

Kal Rubinson

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And when I was considering my last purchase Kevin and Floyd provided almost polar opposite viewpoints of which way to jump.
I am curious about this. Too bad you will not be at RMAF.
 
OP
stunta

stunta

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If you put a bar in that room, speaker placement and room acoustics won't matter as much... just sayin':)

Funny you say that. There was a bar (top right corner niche in the diagram) but I had it removed because the sink did not have proper drainage. It was draining to a pump which was then draining to the sump which was then being drained out by the sump pump. I am already paranoid about flooding (there is an underground stream under our house and the sump pump gets some serious work in winter when the snow melts) so this was one more thing with too many points of failure that would have stressed me out. Did I mention I have a challenging basement?
 

timindy

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We recently moved into a house with a basement and I will stress until this winter passes. Mine has a full bath which drains into a holding tank and then moved on by an ejector pump which moves the sewage up to the main drainage system.

I'm new here and found this thread interesting as I'm moving my system in to the new basement and am looking for larger speakers to replace my Revel M22s. I haven't heard the higher end Revels, but have heard many of the Performa series. I'm a big fan of the Revel sound.
 

andreasmaaan

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@mitchco sorry to shoot down your post earlier. Re-read it today and the tone comes off as pretty harsh, which wasn't my intention. I've never had much correlation between programs like Amroc and real rooms. Despite being rectangular, Stunta's room sounds particularly challenging as there is the internal thin wood panelling with a 1-foot air gap and then solid stone walls. That wood is likely to reflect a bit of mid and upper bass, pass most of the low bass, and flex quite a bit, and the cavity is going to create effects that won't be predictable with simple modelling tools. That was what I wanted to point out. Good to share these tools though.

@stunta I think your wife's advice is on the money, although I do think the Revels and some decent electronics are likely to be a significant step up from your current speakers. If you do go for passive floorstanders, the KEF R700 is another speaker that might be worth listening to. Similar in size and spec to the Revel, but with the mid and tweeter in a coaxial arrangement. Also going very cheap ATM I believe due to the release of the R7 which supersedes it. (And the R7 is ofc another good option.)

You might also want to try placing some rockwool behind the thin wood panelling if you're finding that a smooth bass response is difficult to achieve without treatment.
 
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mitchco

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@andreasmaaan no worries. My experience is different than yours, as I find the calculators match my acoustic measurements closely in several different rooms I have tried this in. After all, it is the physical room dimensions that fundamentally determine the room modes. Sure there is variability if the room is not a rectangle and the wall boundaries are made out of different materials or if it is an open or closed space, all have some impact, but does not take away from the fundamental that the dimensions of the room dominates. I have used this in recording studios as well and there are reasons for not only the shape of the room, but fundamentally there are good room ratios to shoot for (i.e. Bolt area) if one is so lucky to be able to build their own listening room. It makes a huge difference in low frequency sound quality.

My point with the amroc calculator is that one can be listening to their own rooms modes in 2 minutes. For example, in @stunta's room by routing the audio output from amroc web page to the speakers and moving the mouse cursor across the room mode graph, outputs sound. Here I am centred one on the room modes at ~76 Hz. Have a look at the Room 3D plot to show where the pressure zones are. Note stunta's stereo and seating layout. in Post 1. It is right in the pressure zone and around 76 Hz will sound audibly much louder sitting at the couch as compared to frequencies on either side of the room mode:

stuntas room.JPG

Anyway, all in good fun :)
 

andreasmaaan

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Thanks @mitchco. Actually I've also used the Amroc app as a starting point for designing a studio, so I don’t doubt its usefulness for that purpose. But in such a case you have control over the materials.

The thing with @stunta’s room if I understand correctly is that the walls shown in that layout in the OP are thin wood and that there’s a roughly 1-foot gap between them and the outer stone walls. In such a case, lower frequency modes will mostly be determined not by the thin wood boundaries IMHO, as frequencies that low will largely pass through the thin wood and reflect only when they strike the stone wall behind. In fact IMO the lower modes in Stunta’s room are going to be largely determined by the outer stone walls, not the inner wooden ones.

I’m also not sure I understand why it would be useful to listen to a room’s modes. To add treatment and then listen again to try to ascertain by ear if an improvement has been made? Or maybe to help decide by ear where to place speakers or listening seats? Is that what you’re suggesting it can be good for?
 

FrantzM

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Hi

I am ambivalent about Room Treatments. I use to think that this was the MOST important aspect in a system... well .... after the speakers of course.

What I am learning and experiencing with a trio/quatuor of stupidly cheap ($60) subwoofer are forcing me to reconsider. I am more and more understanding Dr Geddes POVs. If you find ways to control your low end response in such a way to have a smooth FR overal in the room (several places in the room) and of course at the listening position, you may be surprised to how good your main actually were (everything else being equal). Cleaning up the bass has a serious almost eerie effect on the rest of the spectrum. Keep in mind that unless you go to stupidly heroic efforts like multiple Bass traps and Helmholtz cavities that could be the size of the room itself (no joke down low under 100 Hz that is what is required), You cannot treat a room for under 100 Hz.. For that you need multiple subwoofers. There seem to have no way around that fact.
You don't need the best subwoofers one can get. Try to learn bass integration with some cheap subwoofers. Ray Dunzl can steer you toward his cheesewoofers, get 2 they are about $200 each then the integration parts come in ... You need the following tools: A miniDSp 2 x 4 ($105) , the miniDSP Advanced Plug-in ($10), The miniDSP Unimik (about $120 calibrated), REW ( $0). A laptop (you have one) and of course some IC and cables (you have some already but I strongly suggest you use Nordost Odin Cable Loom IC + speaker cables for mains speakers ............... :cool:) ... Then you research, you read a lo; t you try, you despair and at the end you will be very surprised by what you are getting from mostly your previous system.

Not saying that Room Treatments are not a good solution. I , however, suggest bass linearization and integration as things you must try before venturing into Room Treatments ...
 

NorthSky

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We recently moved into a house with a basement and I will stress until this winter passes. Mine has a full bath which drains into a holding tank and then moved on by an ejector pump which moves the sewage up to the main drainage system.

I'm new here and found this thread interesting as I'm moving my system in to the new basement and am looking for larger speakers to replace my Revel M22s. I haven't heard the higher end Revels, but have heard many of the Performa series. I'm a big fan of the Revel sound.

Welcome new member. :)
 

DonH56

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Room treatments are generally ineffective at subwoofer frequencies. Mostly they are good for damping higher-frequency reflections that smear the image and all that jazz.
 

NorthSky

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Some people have "lucky" rooms. They don't need additional room treatments, the decor and furniture complements the sound quality.
We all take pleasure from our senses, from our ears, from the decor.

In the future we will have speakers that adapt to each room, and with tunable bass down to five hertz. Some of us will still be here, others will not.

About the BeoLab 90, we're on the right direction for audiophiles, Kal and Don?
 

NorthSky

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View attachment 15825

If this was my room ...

I would use the length instead of the width.
The couch against the wall is a big no no.
Two subwoofers need to be properly positioned.
A preamplifier with state-of-the-art room EQ system (Trinnov, Dirac, Arc, ...) and bass management is essential for movies, IMO.
For stereo and multichannel music...LPs, SACDs, ... the same.

It is not an ultra high-end dedicated analog two-channel stereo hi-fi music listening room. It is an entertaining movie/music room.

If for any reason I would be obligated/restricted by the configuration above, I would get a $300-900/pair of front left/right speakers and a pair of subs from say SVS for roughly $1,400-1,900/pair, and a multichannel preamp with Audyssey MultEQ XT32 on the second hand market for roughly $700.

Grand total: From roughly $2,400 to $3,500

* Move the couch from that back wall...give it twelve inches @ minimum, @ the very least. Put a big painting behind, made of thick wool, or a rug from Afghanistan, or from Morocco.
 
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