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Newbie Room Question

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Hi All,

My question regards room acoustics where one side of the room is missing a wall.

I think many people have this, where the room is an open-floor plan and you have one side that opens into another space. For me, that's the left side. Also, As you can see in the photo, the first surface on the left back is maybe 3' further from the same on the right.

Are there any rules of thumb I should follow here? I just got these ML 40i and I love them. (They are pretty and much more balanced, coherent than my previous Klipsch bookshelves :facepalm:)

Another issue I've been having is that with the rear ports open, there is a ton of bass "gain", if you could call it that. So what I did, I read on a review of these speakers that the reviewer plugged the rear ports. However, it does seem to take away from that really-low (sub-40) response. I'm going to try a "partial" plug so we'll see how that goes.

I was considering creating a 1.5-2'-high U-shaped wood enclosure fitted with acoustic panels to sit on the floor behind the speaker and reflect that bass sooner? Idk, I'm a little lost as to what to do.

For reference, the distance between the speakers is 6' driver-to-driver, and they are toed in about 20 deg. The distance to listening position is 8'2". Distance from back wall is 16" on the right, about 4' to the door on the left.

Would appreciate any help/informed advice I could get!

(keyword 3-sided room)
1656348446625.png

Room - audio.jpg
 

iMickey503

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That Denon I think has DSP functions built in.
Start there first. Look up Room EQ Wizard. Fix those problems in the Low Frequency band first.

Stuffing the PORT is a last RESORT.

try lowering the frequency band at 63 Hertz in the geographic equalizer that's built in to the Denon AVR that you're using first and see how you like that before you continue further.

 
OP
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Okay thanks for your response.

So, the thing is, that foam does help a lot with this effect I’m hearing, but not effecting the higher freq.

I tried what you said about the eq. It does work, but I can’t run direct or pure direct mode like that.

Additionally, I think it’s going too high on the frequencies when doing that.

Anyway, I will continue experiement and see what works. Thank you!
 

Hipper

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With stereo, symmetry is always the ideal. This means the left and right speaker have identical positions where walls, corners, open spaces, whatever, are mirror images of each other. This leads to equal behaviour of all the frequencies. It doesn't make the room good or bad sounding, just balanced between left and right. If you can't have symmetry then you have to work to make it appear symmetrical, such as using room treatment or DSP/EQ. Once you have symmetry you still need to treat the room in some way, with subs, room treatment, DSP/EQ, or a combination of these.

Can you arrange it so that the open space is behind you?

You need to learn how sound that leaves your speakers behaves in a room. It's complicated. A simple summary is that bass (say sounds below 250Hz) behave differently to the higher frequencies (above 250Hz). The 250Hz figure is different for each room and is known as the Schroeder or Transition frequency.

To try to control bass with room treatment you need big items - bass traps up to 40cm square (foam is not very effective at these low frequencies). For the higher frequencies narrower panels will work, as does foam.

Here's a site that has lots of info:

 

tomtoo

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Friendly i would say thats a very,very hard situation.

Not so friendly i would say its a nearly fu#### up situation.

One speaker in the corner and one nearly in the room. Making them sound the same is impossible mission. Even perfect eq'ing helps only partyaly couse the indirect sound is so different.
 
OP
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Best way to learn is to experiment. Your Welcome!
Another question @iMickey503 ...

The speakers came with spikes and round feet.

I tried the spikes to go through my carpet, but the carpet pad sits on top of concrete, so the spikes just rocked back and forth. The idea of them sitting on the concrete like that didn't seem right to me (Opposed to digging into plywood, which is what I think they're for), so I just put the round feet on.

The speakers are really just kind of "floating" on the carpet now. If I touch them and move them around they're very easy tomove/wobbly. Is that a problem? What's the best way to proceed here?

Thanks,

Silviu
 
OP
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FYI from a Greek site that reviewed these:
1656448184046.gif

1656448227434.gif
 

iMickey503

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I don't have any data or experience with speaker spikes on concrete subfloors.
What I can tell you is that if they are rocking back and forth? It's not a good thing. So use the method that works best to secure your speakers.

Spikes are great to lock in the location of your speakers. But the jury is still out about its sound transmission properties.

I have found a few threads about speaker spikes





My very own opinion? I would use the round feet.


About the waterfall graph? I'm not really sure, but it seems like the room is interacting with the speaker quite a bit. I don't think this is an accurate measurement for the performance in your own room.
I have this funny feeling that the performance is actually better than what is shown in the graph.
 
OP
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A73C3A42-FEFE-4CDD-9A78-110D05F178D3.jpeg

I don't have any data or experience with speaker spikes on concrete subfloors.
What I can tell you is that if they are rocking back and forth? It's not a good thing. So use the method that works best to secure your speakers.

Spikes are great to lock in the location of your speakers. But the jury is still out about its sound transmission properties.

I have found a few threads about speaker spikes





My very own opinion? I would use the round feet.


About the waterfall graph? I'm not really sure, but it seems like the room is interacting with the speaker quite a bit. I don't think this is an accurate measurement for the performance in your own room.
I have this funny feeling that the performance is actually better than what is shown in the graph.
Much appreciated @iMickey503

Since I posted this I’ve been experimenting and looking things up.

The first thing is one problem I didn’t mention was this “ringing” whenever I’d talk loud or clap my hands. I put up a bunch of “woven panels” (1/4”) I bought on Amazon to mitigate that, and I think it resolved it because I don’t hear it anymore. (My test was to yell or clap haha, it worked!) - photo attached, arrows —ignore the rowing machine LOL that’s temporary.

There’s this app on my iPad that measures frequencies (see the purple photo). I played a 30hz tone and look at the reverberations it was making. So even though I was playing only 30hz, it crated higher resonant tones up to 200hz. ‍♂️

I emailed with Ethan at RealTraps and the bass problem is basically, without some serious bass trapping, a “mitigation” issue at this point, rather than one to resolve. I think I’ll wait until I move for that resolution, since I intend to have these speakers for 3 years minimum. I might considering getting some bass traps.

HOWEVER, after all this I went through the Audessey EQ system you suggested on Denon’s software using their mic. Actually, you were right, it created a good sound! (I think) at least the bass didn’t sound insane.

It increased the level on the left 1.5db over the right. It also did this: (see attached)

Anyway would love to hear your thoughts I don’t have audiophile friends haha. But also putting this up for others with the same issues to know about.
 

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Soandso

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The speakers are really just kind of "floating" on the carpet now. If I touch them and move them around they're very easy tomove/wobbly. Is that a problem? What's the best way to proceed here?
Mx4, - Maybe consider "mass loading" with something like flat paver stone blocks wrapped in aesthetic colored fabric atop those unstable tower speakers to add compression force down into the underlying carpet.

Alternatively place the speakers on some wood tables with 4 legs you cut short - you'll have a speaker platform that those spaced legs will distribute weight more stably. Below are 2 photos of old wood end tables neighbors discarded which I cut legs off with a hand saw for my desired speaker height - presumably you'd want to find smaller table tops and cut almost all the legs off .

1A10E90A-7938-49B8-9F46-EB36A28FDF0A.jpegE444E4DB-EA96-426D-B60D-DDA4C568ABC7.jpeg

And ... Would you please tell me the name of that iPad app you referenced as origin of your "purple photo?" Thanx in advance.
 
OP
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Mx4, - Maybe consider "mass loading" with something like flat paver stone blocks wrapped in aesthetic colored fabric atop those unstable tower speakers to add compression force down into the underlying carpet.

Alternatively place the speakers on some wood tables with 4 legs you cut short - you'll have a speaker platform that those spaced legs will distribute weight more stably. Below are 2 photos of old wood end tables neighbors discarded which I cut legs off with a hand saw for my desired speaker height - presumably you'd want to find smaller table tops and cut almost all the legs off .

View attachment 215655View attachment 215656

And ... Would you please tell me the name of that iPad app you referenced as origin of your "purple photo?" Thanx in advance.
Hey @Soandso . The app is called “Spectrum”. I appreciate you sharing the ideas on weighting the speakers to the floor. I like the second idea better since these ML’s have a slanted top. I think I’d probably combien the 2 and create a bottom-heavy platform I could dig the spikes into.
 

iMickey503

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Anyway would love to hear your thoughts I don’t have audiophile friends haha. But also putting this up for others with the same issues to know about.
1656576647709.png


I'm no Audiophile. I like music too much.
Thoughts?

The auto setup is a GOOD Base to start.
Fine tune to your ears as you see fit. But take it with Baby Steps. Get a Pen and Paper.

1. Tweak
2. Listen to Tweak.
3. Go back to Before Tweak.

Do this Many times until you are SURE it is Better. Compare with headphones if you need a reference.

You want your room to be a Place you ENJOY being in and Listening to music. So whatever room treatments you purchase? Keep an Eye on design. Surround yourself in a space that welcomes you. Even invites you to be in.

Your perfect room is whatever you make it.
e0f16e9fee75eb7bd0029c97d6aadbad.jpg
 
OP
MajorMajorMajorMajor
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With stereo, symmetry is always the ideal. This means the left and right speaker have identical positions where walls, corners, open spaces, whatever, are mirror images of each other. This leads to equal behaviour of all the frequencies. It doesn't make the room good or bad sounding, just balanced between left and right. If you can't have symmetry then you have to work to make it appear symmetrical, such as using room treatment or DSP/EQ. Once you have symmetry you still need to treat the room in some way, with subs, room treatment, DSP/EQ, or a combination of these.

Can you arrange it so that the open space is behind you?

You need to learn how sound that leaves your speakers behaves in a room. It's complicated. A simple summary is that bass (say sounds below 250Hz) behave differently to the higher frequencies (above 250Hz). The 250Hz figure is different for each room and is known as the Schroeder or Transition frequency.

To try to control bass with room treatment you need big items - bass traps up to 40cm square (foam is not very effective at these low frequencies). For the higher frequencies narrower panels will work, as does foam.

Here's a site that has lots of info:

Thanks @Hipper. I actually ended up reaching out to realtraps and he was helpful. Although, I ended up using the odyssey eq more, opposed to buying traps. It's just that this isn't a "forever" setup so, I'll buy the appropriate traps when I have a better space to start with.
 
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