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Discussion Starter · #1 ·
Hello. I want to start to fix my issue with bass acoustics in my ht/media room and I'll buy corner foam bass traps.
But all of corners in room are totally full with furniture, speakers, etc. On these corners isn't any place to add traps.

So I would like to ask if it'll be OK if I place that traps on the ceiling edges. Or it'll be less effective than I place the same pieces of traps in the corners? (which is impossible, but just theoretically)

I want to do something like this:



thank you
 

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Well I'd just get out the mic and measure the effect compared to having them in the corner (move some furniture and measure with the bass traps in the corner). Try also fastening them high up vertically on the corners as well, to compare, as well as in the ceiling as you show but in the corners instead of the middle.
One experiment is better than a thousand expert opinions.
 

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What exactly are your issues and why do you think bass traps are the solution?
 

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Discussion Starter · #4 ·
I have room 15x15 feet and I have issues with echoes. I want to minimalise them.
I readed some articles and they said, bass traps are good beginning to start removing echoes, especially in smaller rooms.
So I think they will be good solution for the beginning or I'm wrong? Because various web sites said, first traps and then pyramids (if still necessary)

For example when I watch movie I think echoes sounds more booming than something other. Speaking sounds too bassy and strange. I dont think if that's effect of bad bass, I am not a professional. This is my first experience with solving acoustics.

And one more thing. In movie Interstellar for example subwoofer passage at beginning of movie. In one moment bass sounds really wreid. It should get stronger but I hear something like sinusoid of null and peak. Just for a moment, of course not whole scene.
Sorry I cannot describe it better...


In truth, I dont really know what I need for fix that problems. I only thought, bass traps will be a good start. Because I dont have very big budget so I don't want a perfect sound, just average.
Please help me.
 

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^^^

That's all good info to help us help you. :)

Now, tell us what equipment you are using.


Is your room exactly as the pic in your OP or is that just a generic example? Are you actually using nearfield monitors and sitting at a desk or mixing board while listening?
 

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Discussion Starter · #6 ·
no. that's just generic image for demonstrating that "ceiling mount"
I have home theater/media room, not studio.

this is footprint of my room:



this is a side view, for show a fact, that is attic room.



I use subwoofer Jamo SUB 260, speaker set JAMO S 426 HCS 3, older but good yamaha avr (I cant tell you a model number right now, I'm away from it). On floor I have carpet. On one wall I have one framed poster, on opposite two.

edit: for that bass traps, I have actually free 2 corners. Behind rear speakers. But because of attic room, that corner is not very high, only 80cm (2,6 feet).
 

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no. that's just generic image for demonstrating that "ceiling mount"
I have home theater/media room, not studio.

this is footprint of my room:



this is a side view, for show a fact, that is attic room.



I use subwoofer Jamo SUB 260, speaker set JAMO S 426 HCS 3, older but good yamaha avr (I cant tell you a model number right now, I'm away from it). On floor I have carpet. On one wall I have one framed poster, on opposite two.

edit: for that bass traps, I have actually free 2 corners. Behind rear speakers. But because of attic room, that corner is not very high, only 80cm (2,6 feet).

Even more helpful. :)

I don't want to sound condescending, but there's only so much you can expect from a 260w 8" subwoofer. If I was you I would upgrade the sub before worrying about bass traps. ;)
 

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Discussion Starter · #9 ·
But my speaker setup is not any high end, I think that subwoofer is equal to this category.
My 5.0 speaker set cost approx 200 € and the sw cost approx the same price.
I think If I should buy better subwoofer, it will be too much for that class of speakers. It'll be not ballanced.
And anyway... This is my new setup, it was not cheap for me so I really don't want to replace it.

I dont know, but I think if I hear echoes in my room when I say something or when I'm conversating with other person, there is a option to improve sound, without replacing my setup. And not useless. What do you think about it? Maybe forget about bass traps, and look at the pyramid foam?


btw: I forgot to tell you, I run my subwoofer at lowest possible volume level. It still produce a strong basses, in some cases too strong, I dont think its a bad machine for not very demanding listener. I never increase volume, I sometimes think, it is quite too strong at this lowest level.
But strange is this fact: I generate for example 40Hz and doors shaking. I make a 70Hz sound and I hear almost nothing. Isnt this aftermath of bad acoustics?
 

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But my speaker setup is not any high end, I think that subwoofer is equal to this category.
My 5.0 speaker set cost approx 200 € and the sw cost approx the same price.
I think If I should buy better subwoofer, it will be too much for that class of speakers. It'll be not ballanced.
And anyway... This is my new setup, it was not cheap for me so I really don't want to replace it.

I dont know, but I think if I hear echoes in my room when I say something or when I'm conversating with other person, there is a option to improve sound, without replacing my setup. And not useless. What do you think about it? Maybe forget about bass traps, and look at the pyramid foam?


btw: I forgot to tell you, I run my subwoofer at lowest possible volume level. It still produce a strong basses, in some cases too strong, I dont think its a bad machine for not very demanding listener. I never increase volume, I sometimes think, it is quite too strong at this lowest level.
But strange is this fact: I generate for example 40Hz and doors shaking. I make a 70Hz sound and I hear almost nothing. Isnt this aftermath of bad acoustics?
A 200 € speaker package in a room with a 200 € bundle of do-it-yourself bass traps can easily sound better than a 2000 € speaker package in a room with no bass traps. Start with bass traps, and just forget about pyramid foam.


http://arqen.com/acoustics-101/room-setup-acoustic-treatment
 

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Your room is ideal for standing waves with it's identical length and width. But you're talking about echo which is a result of a live room with reflective surfaces. Have you tried foam at first reflection points of the front speakers? Also, I'm sure this isn't it, but have to ask, when listening/watching TV shows or movies, do you turn the TV volume down so you don't have sound coming from TV and sound system? Depending on controls, some systems mute the TV when the audio system is on.

Something to try.
 

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Well I'd just get out the mic and measure ....
What exactly are your issues and why do you think bass traps are the solution?
A 200 € speaker package in a room with a 200 € bundle of ...can easily sound better than a 2000 € speaker package...
The first two responses are spot-on, but the last one is only true if you do the first two:
- use a measurement rig to characterize your room before you make changes
- use that data to identify issues you want to address, then test fix effectiveness with follow-up measurements.


"I have room 15x15 feet and I have issues with echoes. "
Clap your hands together really loud, once, and tell us what you hear.

Flutter echos are common in small spaces with untreated parallel walls. A flutter echo is a higher pitch sound that seems to bounce back and forth across the space. It's easy to fix by simply hanging something on the wall to absorb a little sound, or adding an area rug. This is the kind of problem where acoustic panels excel.


"when I watch movie I think echoes sounds more booming than something other. Speaking sounds too bassy and strange. I dont think if that's effect of bad bass..."
These words (booming, bassy) are usually associated with a tonal imbalance, an excessive amount of bass or treble. One frequent cause is misapplication of speakers, but that's usually fixed by room correction software. I don't find bad reviews on these Jamo speakers (are these yours?) and an older Yamaha AVR may not have YPAO room correction. That leaves sub integration next: how are main speakers seen by the AVR, as large or small? How are the sub's controls set?

Ideally, you want all speakers set to "small" with the AVR applying an 80Hz crossover to the speakers and subwoofer. The idea is to have the sub produce everything below 80Hz. Then adjust the sub's three controls:
- phase for greatest bass output
- crossover at max if using the AVR's crossover
- level at the point where the low-bass range is at the same level as mid- and upper-bass.

Finally, there's speaker placement relative to walls. My center channel has seen several revisions to get this right, as it's in furniture, which acts like a wall. I'd have described the problem like you did - too bassy. The only fix you have is placement. I changed the crossover, which is beyond the scope.

Note that I haven't suggested a single bass trap because your descriptions lead me in other directions. That doens't mean you room won't need some treatment, beyond killing the echos, but you have work to do before you start treating the room. Get something on any bare walls, to get at the echo, and go through your surround set-up to be sure you aren't double-bassing somewhere. Then get some instrumentation, a very basic measurement rig, so you don't have to rely on your ears and language to communicate with us.

HAve fun,
Frank
 

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I think if I hear echoes in my room when I say something or when I'm conversating with other person, there is a option to improve sound
Yup, put down some rugs...get some thick curtains....fat, fluffy furniture. Not bass traps. You need to "deaden" the liveliness of the room before worrying about optimizing bass.


I run my subwoofer at lowest possible volume level. It still produce a strong basses, in some cases too strong
What AVR (Audio Video Receiver) are you using and where is the sub trim set in the AVR?


I generate for example 40Hz and doors shaking. I make a 70Hz sound and I hear almost nothing. Isnt this aftermath of bad acoustics?
You are sitting in a null. Common cures for a null are; move the sub, move the MLP, more subs.
 

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Discussion Starter · #14 · (Edited)
The first two responses are spot-on, but the last one is only true if you do the first two:
Clap your hands together really loud, once, and tell us what you hear.
It depends where am I when I'm doing that clap. When I am at position of center speaker I hear I think no echo. It's strange because when I say something I hear something like booming a little bit.
When I clap hands in a middle of room I hear sound like a small rattling (Maybe?)


how are main speakers seen by the AVR, as large or small? How are the sub's controls set?
All speaker as Small. Here is everything OK. Crossover at 80Hz.
SW: Volume level at minimum, crossover at maximum (200hz), phase at 0.

- phase for greatest bass output
Actually I tried to set phase, but when I play with the knob, I hear almost no difference.
I made for example 40Hz and my friend turn the knob smooth and slowly but I didn't feel any change.


Note that I haven't suggested a single bass trap because your descriptions lead me in other directions. That doens't mean you room won't need some treatment, beyond killing the echos, but you have work to do before you start treating the room. Get something on any bare walls, to get at the echo,
But most of articles on the web says basstraps are actually broadband acoustic element, pyramid foam not.
What do you think about it?


and go through your surround set-up to be sure you aren't double-bassing somewhere.
nope, avr is set correctly. All speakers to small, which set crossover to 80Hz. Bass output is set to SW only.



Then get some instrumentation, a very basic measurement rig, so you don't have to rely on your ears and language to communicate with us.
I am not a professional and I haven't money for do it absolute perfect even with measurement. Only thing I want to do is a basic improvement of acoustic.




Also, I'm sure this isn't it, but have to ask, when listening/watching TV shows or movies, do you turn the TV volume down so you don't have sound coming from TV and sound system? Depending on controls, some systems mute the TV when the audio system is on.
I use only PC, projector and dolby digital live for sound but of course, my avr is only device which receive and produce sound.


Yup, put down some rugs...get some thick curtains....fat, fluffy furniture. Not bass traps. You need to "deaden" the liveliness of the room before worrying about optimizing bass.
As I wrote above, I found everywhere that bass traps is actually broadband material and in most of cases it is enough for basic acoustic treatement. And almost every article say, first bass trap, then other foam (if still required) What's your opinion about this?



What AVR (Audio Video Receiver) are you using and where is the sub trim set in the AVR?
Yamaha RX-V595aRDS, sw crossover at 80hz for each speaker, I think everything is fine here.



You are sitting in a null. Common cures for a null are; move the sub, move the MLP, more subs.
Sorry I described it with wrong words maybe. I already find best place for my sub. Most of frequencies sounds OK but for example 70Hz sounds strange. I hear almost nothing at my seating place. Other basses is hear as powerful and I think ok.
 

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I say treat first reflection points first (with the appropriate treatments) then worry about bass traps.

I asked what your sub trim was set to, not the crossover. ;)

What you are describing (in your previous post and in this post) is a null at 70hz. If the 70hz signal is stronger elsewhere in the room, it is a null at the MLP.
 

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OP - From reading what you describe, I'd suggest a slightly different route.

a) not everyone wants/needs a measurement mic, understood
b) using best practices, focus on your first side wall reflections, this will manage your "slap echo" and improve your front soundstage imaging
c) use the mirror trick http://ethanwiner.com/acoustics.html#rfz
e) also use this free software as ray tracing : *free* software to help determine your first reflection points
d) apply if you can 2" thick treatments + 2" air gap at side wall specific areas; these treatments are for freq above Fs transition freq of approx 250hz
>>many examples of DIY acoustic treatments in this thread http://www.avsforum.com/forum/19-de...s-moveable-corner-traps-not-fixed-frames.html , both side wall, ceiling, and various wall/wall intersection (corner, ceiling)


Broadband wall/wall intersection bass traps.. those will only help decrease your modal ringing, not really increase your bass spl.
Usually 2 subwoofers are best value for $$ to help flatten your overall seat-seat dips/valleys of freq response, then add Broadband wall/wall intersection bass traps to manage your LFE decay time.
 

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Discussion Starter · #17 ·
What is that subwoofer trim? I don't know if my avr supports that feature.

by the way: today I tried to put some pillows in the corners, blankets and duvets on the walls, curtain on the window and I'm noticing a huge difference.
Speech from center speaker is now more natural, not boomed like before.

Subwoofer... ummm I think subwoofer sounds like before, I don't listen any big change.
But I dont know if pillows in corners can do bass trap's job well...

So what's your opinion? start with acoustic pyramids?
 

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The first two responses are spot-on, but the last one is only true if you do the first two:
- use a measurement rig to characterize your room before you make changes
- use that data to identify issues you want to address, then test fix effectiveness with follow-up measurements.
In a small untreated room like that, you don't need measurements in order to conclude bass traps will give you the best bang for the buck, albeit I agree you should still do measurements for absolute verification. Treating flutter echo and early reflections is also very highly recommended of course, but in a small room you should typically always start by placing very thick broadband absorbers in as many corners of the room as possible because peaks and nulls in the frequency response caused by standing waves in a small room are pretty much guaranteed to be the biggest problem and because it's generally a lot easier to deal with the other problems after the bass traps have been installed. In fact every experienced acoustician will tell you that (not just because they want to sell their products, but also because it's the truth).


Some books to read:
"Get Better Sound" by Jim Smith
"Build It Like the Pros" by Rod Gervais
"Recording Studio Design" by Philip Newell
"Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms" by Floyd E. Toole
 

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Futhermore, because your seating is relatively close to the back wall, I would make it another absolute priority to treat the back wall (and the part of the ceiling at and directly above ear level) as much as possible with very thick (as thick as possible) broadband absorption. You don't have to believe this advice... just ask Ethan Winer instead. ;)
 

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But I dont know if pillows in corners can do bass trap's job well...
Not in a million years.
So what's your opinion? start with acoustic pyramids?
From GIK Acoustics website:


We recommend starting with corners first as this is usually the place where you’ll get the most bang for your buck as far as frequency response and decay time. Get the front corners… and the back corners.
Once that’s out of the way, we recommend treating what we call your ‘first reflections’ {...}
http://www.gikacoustics.com/the-basics-bass-traps-diffusion-panels


Here's another great article that explains the utmost importance of installing bass traps:
http://www.audioholics.com/room-acoustics/acoustics-facts-and-fiction


Best piece of advice I am able to give you: whatever you do, don't listen to the noobs! :D
 
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