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post #31 of 146 Old 04-13-2012, 04:29 AM
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Quote:
Originally Posted by Digital_Chris View Post

I didn't realize Superchunks were considered "small" bass traps. Also, listening position cannot be changed. Not that critical to me anyway..

sq area/coverage is a key factor with porous LF absorbers - and you do not have much coverage with two small superchunks.

also, you want to generate the waterfall plot to see the LF modal ringing / LF decay times...
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post #32 of 146 Old 04-13-2012, 04:50 AM
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Quote:
Originally Posted by Digital_Chris View Post

Well, since the Dayton mic was backordered till the 10th, I decided to order the Behringer ECM8000 mic from BHPhotoVideo, the price was justified because of the free and quick shipping (NY to CT), plus, I grabbed the ACT box you recommended, local.

Is there a calibration file somewhere for this mic as well?

Frankly, this mic has flat enough response right out of the box, that you may find a relevant calibration file to be superfluous. Over the range that your ear is most critical of, it is far flatter than it needs to be.

I've done direct comparisons of ECM8000s to DPA 4006's, and the differences I observed were within the calibration curve of the 4006s.

Calibration of microphones is of primary use when the sensitivity of the mic is the issue - IOW how much voltage comes out when a broadband midrange signal at a certain SPL is applied.

For room tuning the actual sensitivity of the mic is not much of an issue as long as the mics are within a few dB of each other. Most of the work you are going to do is going to be about comparisons so if the mics match each other reasonably well, that is that. There is an exposure with ECM 8000s, because over time some of them seem to loose a lot of sensitivity and should then be discarded and replaced.

I can see someone being destructively led down a rough path if he had several measuring mics whose sensitivity was not in the same ball park. Its a good idea to compare your mics with each other every time you start up a new project or come back after a few weeks.
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post #33 of 146 Old 04-15-2012, 10:29 PM - Thread Starter
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Quote:
Originally Posted by localhost127 View Post

also, you want to generate the waterfall plot to see the LF modal ringing / LF decay times...

Will do Local, thanks.


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post #34 of 146 Old 04-15-2012, 10:30 PM - Thread Starter
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Quote:
Originally Posted by arnyk View Post

Frankly, this mic has flat enough response right out of the box, that you may find a relevant calibration file to be superfluous. Over the range that your ear is most critical of, it is far flatter than it needs to be.

I've done direct comparisons of ECM8000s to DPA 4006's, and the differences I observed were within the calibration curve of the 4006s.

Calibration of microphones is of primary use when the sensitivity of the mic is the issue - IOW how much voltage comes out when a broadband midrange signal at a certain SPL is applied.

For room tuning the actual sensitivity of the mic is not much of an issue as long as the mics are within a few dB of each other. Most of the work you are going to do is going to be about comparisons so if the mics match each other reasonably well, that is that. There is an exposure with ECM 8000s, because over time some of them seem to loose a lot of sensitivity and should then be discarded and replaced.

I can see someone being destructively led down a rough path if he had several measuring mics whose sensitivity was not in the same ball park. Its a good idea to compare your mics with each other every time you start up a new project or come back after a few weeks.

Thanks for the info


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post #35 of 146 Old 04-16-2012, 01:22 PM
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I'm confused by your description of superchunks. Ideally, they should be floor-to-ceiling and made of OC703 rigid fiberglass. The puffy stuff lacks the mass. You should compare the RT60 results and the waterfalls of your before and after measurements.

I have superchunks in all four corners. They cut down the reverbration time and cleaned up the bass but did not address the two main room modes.

Even if your measurements didn't show much of a change, did you like the difference in sound?
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post #36 of 146 Old 04-16-2012, 03:00 PM
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Quote:
Originally Posted by Will_Morr View Post

I'm confused by your description of superchunks. Ideally, they should be floor-to-ceiling and made of OC703 rigid fiberglass. The puffy stuff lacks the mass.

flow-resistivity is the key value with respect to porous absorbers...
...a common misconception that denser material is better --- but thick absorbers of pink fluffy attic insulation (~5000rayls/m flow-resistivity --- loosely filled; NOT compressed) will perform better than OC703. porous absorbers need to be sufficiently thick to be effective to the longer wavelengths, and as the trap becomes thicker and thicker you will want to use a material with lower flow-resistivity.


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Originally Posted by Will_Morr View Post

You should compare the RT60 results and the waterfalls of your before and after measurements.

rt60 is not relevant in small acoustical spaces; there is no appreciable reverberation and thus, no reverberant sound-field. also, there is no critical-distance, of which rt60 needs to be measured past.

Quote:
Originally Posted by Will_Morr View Post

I have superchunks in all four corners. They cut down the reverbration time and cleaned up the bass but did not address the two main room modes.

they can help greatly with LF decay times and modal ringing (no reverberation). porous insulation is a velocity-based absorber - thus, they need to be placed in areas of high particle velocity for those relevant wavelengths in order to be most effective. pressure-based (resonator) traps are far more effective for the lower octave issues.
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post #37 of 146 Old 04-16-2012, 08:22 PM - Thread Starter
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Quote:
Originally Posted by Will_Morr View Post

Even if your measurements didn't show much of a change, did you like the difference in sound?

I actually didn't notice any sound difference at all, and my superchunks aren't exactly floor to ceiling, they are about 3-4 inches off the floor and probably about 8 to 10 inches from the ceiling.


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post #38 of 146 Old 04-17-2012, 12:34 PM
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Quote:
Originally Posted by localhost127 View Post

flow-resistivity is the key value with respect to porous absorbers...
...a common misconception that denser material is better --- but thick absorbers of pink fluffy attic insulation (~5000rayls/m flow-resistivity --- loosely filled; NOT compressed) will perform better than OC703. porous absorbers need to be sufficiently thick to be effective to the longer wavelengths, and as the trap becomes thicker and thicker you will want to use a material with lower flow-resistivity.

Interesting. Now I need to spend the time to figure that out



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Originally Posted by localhost127 View Post

rt60 is not relevant in small acoustical spaces; there is no appreciable reverberation and thus, no reverberant sound-field. also, there is no critical-distance, of which rt60 needs to be measured past.

I don't disagree that the value itself is not relevant, but making the measurement is helpful to see if you have a room that is too reflective to begin with. If it is, you can use broadband absorption to help clean up the mess. If the room is not too reflective, the RT60 will tell you that you should be careful with how much additional absorption you put in the room or it becomes too "dead".


Quote:
Originally Posted by localhost127 View Post

they can help greatly with LF decay times and modal ringing (no reverberation). porous insulation is a velocity-based absorber - thus, they need to be placed in areas of high particle velocity for those relevant wavelengths in order to be most effective. pressure-based (resonator) traps are far more effective for the lower octave issues.

Agreed. The LF decay and modal ringing was what I was going for above, rather than the reverbration time. The OP's description made me think that the floor and ceiling corners were untreated which is where he would get better results rather than treating "ear-level".
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post #39 of 146 Old 04-17-2012, 05:53 PM - Thread Starter
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I've finally got around to taking some measurements with my new ECM8000 mic and ART dual pre. I started off with the LF measurements first (10-200hz) so I could see how the room acts with and without the superchunk bass traps. I will try to be as thorough as possible. Gear is listed below...

Marantz SR5005 AVR
Behringer DSP1124P
Behringer EP4000 powering subs
(4) FiCar 18" IB Drivers in Line Array on front wall
LCR Econowave Speakers
Behringer ECM8000 mic with generic cal file from this site
ART Dual Pre sound card

AVR Settings:

Bass Settings: SW Mode - LFE (also have a choice for LFE+Main)
LPF for LFE - 120hz

Speaker Config : All speakers set to small

Crossover Freq : Front/Center - 60hz
Surround/Surround Back - 80hz

Room Dimensions are 18 x 10.5 x 7

Front eyes - roughly 9.5' from screen

Rear eyes - roughly 12.5' from screen

Subs in Line Array on lower portion of front wall

I took a measurement at front center seat and rear center seat to get a baseline of the rooms response. As figured, they both sound different, the LFE at the rear seats is stronger and more tactile while the front seats are not as much. I was hoping the superchunk bass traps would help with this... to a point I guess it did, not NEARLY as much as hoped, I could have been mislead by my ignorance of course..

Front Center Seat before Superchunks



Front Center Seat after Superchunks



Overlayed



Rear Center Seat before Superchunks



Rear Center Seat after Superchunks



Overlayed



After all graphs were taken, the db levels seem to be off, I'm guessing that the sound card level or avr was a little off? If you recommend new measurements, I can do that.

The biggest let down is the difference from no bass traps to both superchunks. Unfortunately I don't have the room for superchunks up front but I was hoping the two in the rear would make a noticeable difference, I was let down

The superchunks are about 5.5' tall, a few inches off the floor (to match my wall panels), to 6"-8" from the ceiling. I can take pictures if you would like. They are 36" faced and filled with pink fluffy insulation.

The only big difference was in the rear seat at about 66hz, it took about 15db out of the humongous dip, other than that, no big change

Below is the link to my REW files so you can take a look for yourself. If you want pictures of the room, I can do that as well. Thanks guys

http://www.sendspace.com/filegroup/g...b4biRvHXdjkKhF


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post #40 of 146 Old 04-17-2012, 05:54 PM - Thread Starter
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Here are the waterfall graphs as well, I couldn't figure out how to overlay them but I figured it was worth posting these anyway...

Before Superchunks front center seat...



After Superchunks front center seat...



Before Superchunks rear center seat...



After Superchunks rear center seat...



Any thoughts?


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post #41 of 146 Old 04-17-2012, 07:14 PM - Thread Starter
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And here are a couple of ETC plots from tonight. They are from 10-20k sweeps from the left and then the right main speaker. I'm not sure how to run tones through my center channel, any tricks I'm missing?

Here are the graphs...

Right channel...



Left channel...



I'm still not too sure how to read these though, maybe I'll have some time tonight at work to read up on this.

Let me know what you think


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post #42 of 146 Old 04-18-2012, 12:52 AM - Thread Starter
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Oops, looks like I may have generated the wrong graphs, these don't look like other users ETC graphs. To generate these, I went to "overlays" and then "ETC" because I didn't see an "ETC" tab in the main graph window.

EDIT: Sorry sorry sorry sorry, looks like I have the wrong time range set. I have it set from 0-2.00 seconds while others seem to have theirs set from 0-40ms, is that the usualy range? Either way I'll reset those later in the morning and repost


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post #43 of 146 Old 04-18-2012, 06:10 AM - Thread Starter
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Graphs have been replaced, those look better, now you may let me know what you think


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post #44 of 146 Old 04-18-2012, 06:24 AM
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Quote:
Originally Posted by Digital_Chris View Post

I actually didn't notice any sound difference at all, and my superchunks aren't exactly floor to ceiling, they are about 3-4 inches off the floor and probably about 8 to 10 inches from the ceiling.

The Superchunks seem to be misleadingly named. I see nothing super about them. It usually takes much more to make a significant difference at bass frequencies. Either get more or switch your approach to other kinds of sound treatments.
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post #45 of 146 Old 04-18-2012, 04:02 PM - Thread Starter
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Quote:
Originally Posted by arnyk View Post

The Superchunks seem to be misleadingly named. I see nothing super about them. It usually takes much more to make a significant difference at bass frequencies. Either get more or switch your approach to other kinds of sound treatments.

My expectations are just going by other users impressions by using them, which have all been positive. Can you recommend another type of LF treatment that is reasonably sized?


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post #46 of 146 Old 04-18-2012, 04:02 PM - Thread Starter
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So, I was getting sick of how slow my mini laptop was for running programs including REW so I decided to setup my macbook pro. All went well after a bit of fooling around

My graphs are a bit different now, all are posted below...

Left Channel: (FULL - SMOOTH - ETC - WATERFALL 10-300hz - WATERFALL 10-20khz)











Center Channel: (FULL - SMOOTH - ETC - WATERFALL 10-300hz - WATERFALL 10-20khz)











Right Channel: (FULL - SMOOTH - ETC - WATERFALL 10-300hz - WATERFALL 10-20khz)











I hope you like graphs!

I'm not completely sure how to read the waterfalls or the ETC's yet, any help or guidance would be great


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post #47 of 146 Old 04-18-2012, 05:31 PM
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Quote:
Originally Posted by Digital_Chris View Post

My expectations are just going by other users impressions by using them, which have all been positive. Can you recommend another type of LF treatment that is reasonably sized?

If you are handy, DIY is the way to go. If you aren't, this could be your opportunity to learn a little wood working.
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post #48 of 146 Old 04-18-2012, 05:33 PM
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My thoughts are that you got what I would expect for what you have installed. You have two superchunks in your back corners at ear level. You got some improvement in the 100 Hz to 200 Hz range. I think you would do better floor-to-ceiling.

The peak at 60 Hz is likely a room mode and it is too low for the superchunks to be effective. The sharp dip at 100 Hz may be quarter wave cancellation based on the distance from your speakers to the wall.

Just guesses but worth researching.
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post #49 of 146 Old 04-18-2012, 08:04 PM - Thread Starter
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Quote:
Originally Posted by arnyk View Post


If you are handy, DIY is the way to go. If you aren't, this could be your opportunity to learn a little wood working.

Yes, I am quite handy... What types of treatment are you recommending?


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post #50 of 146 Old 04-19-2012, 05:12 AM
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Quote:
Originally Posted by Digital_Chris View Post

Yes, I am quite handy... What types of treatment are you recommending?

Serious bass traps. Your room appears to have some obvious issues @30, 60, and 100 Hz. 30 Hz bass traps are a challenge. I'd bet that if you dealt with 60 Hz & 100 Hz well, the rest would fall into line.

Project wise - pick up a box of 705 and see what happens when you experimentally deploy it around the room, particularly in corners. Remember that spacing absorbers from the wall can greatly improve low frequency extension.
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post #51 of 146 Old 04-19-2012, 05:44 AM
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Are you able to treat the front two corners in your room? If so, why not just go buy a roll of pink fluffy and temporarily set it up in those corners, take some more measurements to see impact. If good, you can use the fluffy there, or build some 703/705 superchunks and use the fluffy in your attic for those cold winter nights in CT. If it doesn't help, you haven't spent a lot of money to find out.

Floyd

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post #52 of 146 Old 04-19-2012, 06:51 AM
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Quote:
Originally Posted by Digital_Chris View Post

No room treatments have been applied either, superchunk bass traps are waiting to be installed though

Your procedure is right. Get the low frequencies under control first.
Didn't find mention of room size/listening and speaker position.
Draw us a floor plan and take some pictures!
And take Fottos and Arnys advice - source some cheap 'pink' insulation to fill up all your corners temporarily, play with your listening position forward-backward to get out of major nulls. When modal freq. is under control, THEN look at what can be done with imaging/intelligibility/coloration, guided by ETC graphs of listening positions you wish to optimize. You don't need 120dB range for ETC display, we need to see where and with what gain the reflections are impeding the listening position - about 30-50dB.
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post #53 of 146 Old 04-19-2012, 04:21 PM - Thread Starter
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Unfortunately, I don't have the room upfront to add bass traps, I mentioned that earlier in the thread but I understand how it could have gotten missed. The room is on the small side as well so I don't have the room to start placing thick traps of 705 around the room. I'm just trying to work with what I got, not asking for perfection (just so you guys don't get the wrong idea of this thread)

My room dimensions are roughly 18' x 10.5' x 7'.

LCR speakers are horn designed econowaves and are flush mounted into the front wall. Subs are infinite baffle design in a line array across the front wall also. First row of seats is just under 10' from speakers and rear seats are about 14' from front wall. There are 2 rows of 3 seats. You can brows photos here

Bass traps are about 4" off the ground and just about a foot from the ceiling. They were built that way to match the height of my designed wall panels.









Here is a shot of one of the front corners, no room for traps unfortunately...



When I think of more details, I will add them


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post #54 of 146 Old 04-20-2012, 04:46 AM
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Quote:
Originally Posted by Digital_Chris View Post


Here is a shot of one of the front corners, no room for traps unfortunately...



When I think of more details, I will add them

No matter what people say here about using low density fiberglass, the fact is that the same thickness of higher density fiberglass can be more effective at lower frequencies. Adding density works right up until you turn your absorber into a reflector. I've never seen that done with 705.
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post #55 of 146 Old 04-20-2012, 05:29 AM
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Quote:
Originally Posted by arnyk View Post

No matter what people say here about using low density fiberglass, the fact is that the same thickness of higher density fiberglass can be more effective at lower frequencies. .

this is entirely incorrect.
first of all, gas-flow-resistivity is the key value regarding the porous insulation, NOT density as perpetually propagated so often.

porous insulation is a velocity-based absorber and as such, needs to be placed into areas of relatively high particle velocity in order to be most effective. at low frequencies (long wavelengths), this means very thick traps (or large air-gap spacing from rigid boundary) are required. however, as you make the LF absorbers thicker and thicker, you will want to use a material with lower flow-resistivity.

the acoustical impedance plays a large role and any sudden change will result in a reflection regardless of the material. it would actually be ideal to start with a light fibre with impedance close to that of air, and then slowly increase GFR as the porous insulation approaches the rigid boundary.

if constricted to thin traps, then a denser (higher GFR) material will perform better - but there is little advantage to using thin porous absorbers for LF absorption regardless of material used --- the insulation needs to be placed into areas of high particle velocity to be most effective, period. if this is not an option, or you need attenuation at the lower octaves, then pressure-based resonator traps (VPR, membrane, helmholtz) are available. and since they are pressure-based absorbers, their optimal placement is directly on the boundary where pressure is maximized and velocity approaches zero.

if unwilling to experiment and design your own, there are commercial products available:
http://www.rpginc.com/product_Modex_Broadband.cfm
http://www.rpginc.com/product_Modex_Corner.cfm
http://www.rpginc.com/product_Modex_Edge.cfm
http://www.rpginc.com/product_Modex_Module.cfm
http://www.rpginc.com/product_Modex_Plate.cfm


the transfer function formulas are available and you can experiment with a porous absorber calculator or utilize AFMG SoundFlow (free for 30-day trial).

pink fluffy has a flow-resistivity of ~ 5000rayl/m



and this is before we even get into discussion of modifications to the speed of sound as the pressure-wave is passing through the porous insulation...

Quote:
Originally Posted by arnyk View Post

Adding density works right up until you turn your absorber into a reflector. I've never seen that done with 705.

so then why don't you provide the optimal flow-resistivity and thickness for such an application?

-----------------------------

the user's issue is lack of surface area coverage - plain and simple.
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post #56 of 146 Old 04-24-2012, 12:53 PM
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Chris,

Ive been dealing with some of the same issues as you. No ability for ANY corner bass traps, more pronounced bass in the second row than the front, and very limited places to put the subs (in your case, only ONE place ) I feel your pain brotha, and I cant stress enough how the proper combination will help you. One thing that might help in running your graphs is to not assum you can tame EVERYTHING with room treatment, you have the BFD and audyssey after your preliminary eqing to also aid in your quest for a flat bass response. Try some filters on the BFD at the 28hz and 60hz peaks to pull those down a shade and see what you think. Dont quit on the room treatment stuff either! Just give some other things a tweak and see where you get. Peaks are better than nulls IMO so go after those and redo your waterfalls and whatnot, see if they clean up a little Ill be following your thread closely and will continue to post any findings I have in the same search for "better bass up front"

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post #57 of 146 Old 04-24-2012, 05:22 PM - Thread Starter
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Thanks beast, I'm going to take a few more graphs tonight possibly. I popped in the movie hot fuzz last night and was happy with the sound for the most part, but there are definitely some sounds that just sound boomy and its not just the bass, I'm not sure of another way to describe it, maybe I should say it sounds muddy? Either way, it doesn't sound right. It's like some of the sounds are just louder than they should be, louder than the rest of the movie.

There are definitely plenty of parts in that movie and others I have watched too, that the dialogue isn't 100% intelligible either. A lot of the times when it's intelligible, it's because it sounds lower in volume than the rest of the movie. I'm not sure if room treatments would help this because I don't see how they could help in bringing up the volume but it just doesn't sound right.

Also, I popped in the movie Tron this morning to demo to a friend and he sat in the backseat where I knew the bass would be boomier than the rest of the room, so I turned the subs down a tick and had the volume at -15 rather than -10 where I would normally have it, and the bass was just way overpowering, the dialogue and other action sounds were fine, it's just that the bass was way too loud/strong, I don't get it

God, I just want this room to sound awesome and at the same time I feel like I'm never going to get it to that point


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post #58 of 146 Old 04-24-2012, 05:59 PM
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Quote:
Originally Posted by Digital_Chris View Post

God, I just want this room to sound awesome and at the same time I feel like I'm never going to get it to that point

The issues are pretty straightforward and all focus on one chart:



You have a resonance at ~58 Hz or so at a level of 76 dB. At 20 KHz, your response is down to 37 db for whopping ~40 db variation in response! I don't know what Mic you used and if this is a calibrated setting. But even if we back off and look at the response at 5 Khz, you are at ~54 dB for a very large difference of 22 dB. While some amount of bass boost is desirable, you don't want to have such large differential.

The first fix then is to pull down that peak at 76 db with a parametric EQ. You can stand dropping that by 10 db. If you did that, a lot of boominess will go away and the bass would not overwhelm the rest of the sound as it is doing now. You will lose some of your sub power with that but with four of them in front, I assume you still have sufficient. If you do not, you can increase the gain for the whole region some. There is a list of DSPs people use in REW. Select the "EQ" window and you see them in the drop down list. The few hundred dollars on one of these is well worth the price and a necessary item no matter what acoustic product you put in your room. You will always have fluctuations in the response.

For a much higher-end implementation of this, take a look at this article on low frequency room optimization. As you see there and was noted by the beastaudio above, there are a lot of tools at your disposal and you should not limit things to just acoustic products. Our room is professionally designed including computer modelling and lots of acoustic products yet it still benefited from the techniques in that article.

You have a nice looking room and you will be able to improve it sound a lot relative to where it is now.

Amir
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post #59 of 146 Old 04-24-2012, 06:04 PM
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One more thing: run the graph in 1/12th when optimizing bass. Turn off all other speakers and try to linearize the subs by themselves that way first, not worrying about the crossover region. Then look at both being on and getting a smooth response during the crossover. Make sure your subs have proper output that is clean up to the crossover range. Listen to them playing for example 80 to 100 Hz by themselves to make sure they sound clean. If not, filter that out.

Amir
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post #60 of 146 Old 04-24-2012, 11:18 PM - Thread Starter
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Quote:
Originally Posted by amirm View Post

You have a resonance at ~58 Hz or so at a level of 76 dB. At 20 KHz, your response is down to 37 db for whopping ~40 db variation in response! I don't know what Mic you used and if this is a calibrated setting. But even if we back off and look at the response at 5 Khz, you are at ~54 dB for a very large difference of 22 dB. While some amount of bass boost is desirable, you don't want to have such large differential.

I agree, it is odd, I'm not sure why my response drops off dramatically that early. I used the Behringer ECM8000 mic with the generic calibration file from the REW forum. Maybe I can do a sweep with the mic right in front of the speaker(s) to see if it's the speaker or room? Could it be the AVR that is causing the decent?

Quote:
Originally Posted by amirm View Post

The first fix then is to pull down that peak at 76 db with a parametric EQ. You can stand dropping that by 10 db. If you did that, a lot of boominess will go away and the bass would not overwhelm the rest of the sound as it is doing now. You will lose some of your sub power with that but with four of them in front, I assume you still have sufficient. If you do not, you can increase the gain for the whole region some. There is a list of DSPs people use in REW. Select the "EQ" window and you see them in the drop down list. The few hundred dollars on one of these is well worth the price and a necessary item no matter what acoustic product you put in your room. You will always have fluctuations in the response.

I do have a FBD inline between the AVR and the EP4000, the 1124 I believe, so I will be able to tame those peaks. Will that one adjustment of -10db at 58hz make that much of a difference in the overall sound? I got the idea that it will take multiple adjustments and dramatic room treatments to cure most of that boomy bass, hopefully I'm wrong?!

Quote:
Originally Posted by amirm View Post

For a much higher-end implementation of this, take a look at this article on low frequency room optimization. As you see there and was noted by the beastaudio above, there are a lot of tools at your disposal and you should not limit things to just acoustic products. Our room is professionally designed including computer modelling and lots of acoustic products yet it still benefited from the techniques in that article.

You have a nice looking room and you will be able to improve it sound a lot relative to where it is now.

Thanks for the encouragement, I hope you're right. I just can't help but feel that no matter what I do, the room will not change in sound. Dumb thought I know, but until I make a change that I can honestly hear, I will continue to think that way

Quote:
Originally Posted by amirm View Post

One more thing: run the graph in 1/12th when optimizing bass. Turn off all other speakers and try to linearize the subs by themselves that way first, not worrying about the crossover region. Then look at both being on and getting a smooth response during the crossover. Make sure your subs have proper output that is clean up to the crossover range. Listen to them playing for example 80 to 100 Hz by themselves to make sure they sound clean. If not, filter that out.

What do you mean by making sure that my subs have clean proper output and how would I filter the unwanted dirtyness out?

Thanks a lot amirm


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