Whoa… I see now that the 200 Hz tone is ringing to 1.6 seconds whether it is inside or outside.
- cabinet?
- driver?
- crossover?
-
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Help with my room and ringing (is this ringing????)
- Thread starter Nwickliff
- Start date
Whoa… I see now that the 200 Hz tone is ringing to 1.6 seconds whether it is inside or outside.
I fear suggestions will drown in all the different ideas shared here, but here are some:
1. Equalizing the speakers flat in the listening position will not yield a good result because the response there isn't minimum phase. The speakers should eq'ed in nearfield (basically anechoic) above the Schroder frequency without the room response. And apply only shelving to the response in the listening position to acquire the desired graph and without equalizing peaks and dips. Only EQ very low freq. peaks and do this by ear so you know it's an improvement. Reducing even low freq. peaks by too much (more than 3 dB) is not always beneficial.
2. You have to apply acoustic treatment here to get a good result and should start there before EQ. Obviously you can't fill the room with loads of treatment, so you focus on the early reflections point above the Schroeder frequency. That means you should treat both reflection points at the right sidewall, part of the ceiling area between the speakers and listening position, and if possible part of the brick wall behind you. Don't worry about the left sidewall where the distance is long besides furnitures, blinds or drapes.
Perhaps you can use some absorption panels on the right side with feet that can be moved away when not listening? Unless it's a RPG Broadsorbor, preferably don't use thinner panels than 4" and 6" is better. 3" thick ones can be a compromise that's ok though when not using too many. You distance to the brick wall is probably sufficient to use diffusors there rather than absorption panels. Arithemetic Diffuse Signature or Elite would be great.
If you don't have the possibility of using proper absorptive panels on the right side, at least consider some smaller ones with print images that can work like art together with wooden blinders in front of the windows.
Getting speakers with a uniform directivity from minimum 500 Hz to 8KHz would also help a great deal and something to consider down the road. But with no room treatment, it will always be a huge compromise no matter how good the speakers are IMO. You can EQ the speakers (to a large degree) but can't really EQ the room.
1. Equalizing the speakers flat in the listening position will not yield a good result because the response there isn't minimum phase. The speakers should eq'ed in nearfield (basically anechoic) above the Schroder frequency without the room response. And apply only shelving to the response in the listening position to acquire the desired graph and without equalizing peaks and dips. Only EQ very low freq. peaks and do this by ear so you know it's an improvement. Reducing even low freq. peaks by too much (more than 3 dB) is not always beneficial.
2. You have to apply acoustic treatment here to get a good result and should start there before EQ. Obviously you can't fill the room with loads of treatment, so you focus on the early reflections point above the Schroeder frequency. That means you should treat both reflection points at the right sidewall, part of the ceiling area between the speakers and listening position, and if possible part of the brick wall behind you. Don't worry about the left sidewall where the distance is long besides furnitures, blinds or drapes.
Perhaps you can use some absorption panels on the right side with feet that can be moved away when not listening? Unless it's a RPG Broadsorbor, preferably don't use thinner panels than 4" and 6" is better. 3" thick ones can be a compromise that's ok though when not using too many. You distance to the brick wall is probably sufficient to use diffusors there rather than absorption panels. Arithemetic Diffuse Signature or Elite would be great.
If you don't have the possibility of using proper absorptive panels on the right side, at least consider some smaller ones with print images that can work like art together with wooden blinders in front of the windows.
Getting speakers with a uniform directivity from minimum 500 Hz to 8KHz would also help a great deal and something to consider down the road. But with no room treatment, it will always be a huge compromise no matter how good the speakers are IMO. You can EQ the speakers (to a large degree) but can't really EQ the room.
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Would it be possible to measure one speaker indoors (much less background noise) and try to shield it from above and the sides (a bit off from the speaker) with something absorbent so the room is more out of the equation and then measure from a meter away?
And then measure around 83dB or so (and higher if you have more background noise)? Because I am not a pro but I don't like the measurement from outdoors.
I don't know what others think but the measurement from outside looks off in the waterfall plot. But like I said I am not a pro.
And then measure around 83dB or so (and higher if you have more background noise)? Because I am not a pro but I don't like the measurement from outdoors.
I don't know what others think but the measurement from outside looks off in the waterfall plot. But like I said I am not a pro.
ernestcarl
Major Contributor
You can create quasi-anechoic measurements indoors and even make a more modern spinorma out the it:
How to make quasi-anechoic speaker measurements/spinoramas with REW and VituixCAD
Quasi-anechoic measurements are a way to capture the 'real' frequency response of a speaker without the influence of a room. They are called 'quasi-anechoic' because they have the potential to get you really close to the results one might achieve with a non-reflective environment like an...
www.audiosciencereview.com
*But you can also still create an approximated listening window (LW) response indoors to be used as a generalized template to create your own shelving EQ by spatially averaging a bunch of measurements together as well.
Below I've combined indoor derived quasi-anechoic measurements (+- 60 deg horizontal and +-15 deg vertical of my coax S8 monitor) and separate in-room measurements across the whole listening couch (+-30 deg & 100x sweeps
rms averaged), also merging and comparing it side-by-side with another third-party reviewer's axial response to come up with some simple yet "tailored" HF shelving filter of my own:Trace 5 (axial response) was extracted from the ff. graph from a scanned Resolution Magazine Review:
Yikes! super-duper blurred, but serviceable enough.
It ain't identical to my own very flawed (in-room) quasi-anechoic FR, so I figured why not use it just as an additional separate point of reference, too.
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ernestcarl
Major Contributor
For waterfall plots, the noise of the environment has to be very low to not include any spurious contamination. I don't bother to look at it nowadays myself, and much prefer the spectrogram wavelet and decay views in REW.
Also note the appearance settings... and the level the measurement was taken.
dasdoing
Major Contributor
probably coming back from the hall in the back
1.6 seconds would be about 1600 feet… It would be one hell of a hall way. It could be doing like the Pong game, but the outside measurement was also 1.6 seconds (II think)… So it must be a cabinet resonance??
dasdoing
Major Contributor
dasdoing
Major Contributor
if you play a dirac impulse you should hear where that tail is coming from. or just clap you hand. If I clap I can hear a tail from outside my room
Yeah, trhe point was more the time it lasted.
Which was also a reason to do it outdoors.
The 36” measurement should have dropped 60 dB by 1 second, just from R^2.
