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New Home = where to locate the speakers?

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Coach_Kaarlo
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Thread Starter #42
Update.

RED speaker positioning has been measured, and adjusted and measured again, and listened - and repeated a few more times.

Not surprisingly the pre-room correction measurements were reasonable, but had a couple of deep nulls, right in the heart of much music.


FIRST TEST - SWEEP V MMM - DAC ONLY.jpg


FIRST TEST - DAC ONLY.jpg

FIRST ITERATION - DAC ONLY.jpg



So I moved speakers around, and changed the LP accordingly until I found a reasonable compromise. Working out where the mode is generated is helpful - width or height mode for example. My method is to simply play a tone at the problem frequency and move the mic around to determine where the nulls are and where the peaks are, seems like a fast way to avoid moving speakers more than required.

The effort of moving things a hundred millimeters or so gave the following result - generally much better through the mid range.

DAC ONLY FINAL - PHASE.jpg

DAC ONLY - FINAL.jpg


Then I ran DIRAC 3.0 on my miniDSP, and re-measured the results, adjusting the correction to get the best compromise - in the end not much measurable difference, but audibly much better mainly due to the impulse correction I expect. Difference with and without DSP is subtle.

DAC ONLY V DSP DIRAC 3.0 - FINAL.jpg

DSP DIRAC 3.0 - FINAL.jpg

DSP DIRAC 3.0 - FINAL - SPECT.jpg

BEFORE DAC ONLY V FINAL DSP DIRAC 3.0.jpg

BEFORE DAC ONLY V FINAL DSP DIRAC 3.0 - SPL.jpg


Next steps are to measure the outdoors speaker position, and perhaps get a better idea how good it can be. Then work backwards. The DSP is adding clarity and fixing impulse and timing issues L to R but it also seems to add a layer of audible dullness to the sound. The clarity with the DAC only (playing one channel only) is far greater. So something going on with the combined sound of both channels.

Comments and suggestions are welcomed.
 

dasdoing

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#43
Update.

RED speaker positioning has been measured, and adjusted and measured again, and listened - and repeated a few more times.

Not surprisingly the pre-room correction measurements were reasonable, but had a couple of deep nulls, right in the heart of much music.


View attachment 83012

View attachment 83013
View attachment 83014


So I moved speakers around, and changed the LP accordingly until I found a reasonable compromise. Working out where the mode is generated is helpful - width or height mode for example. My method is to simply play a tone at the problem frequency and move the mic around to determine where the nulls are and where the peaks are, seems like a fast way to avoid moving speakers more than required.

The effort of moving things a hundred millimeters or so gave the following result - generally much better through the mid range.

View attachment 83016
View attachment 83009

Then I ran DIRAC 3.0 on my miniDSP, and re-measured the results, adjusting the correction to get the best compromise - in the end not much measurable difference, but audibly much better mainly due to the impulse correction I expect. Difference with and without DSP is subtle.

View attachment 83024
View attachment 83027
View attachment 83026
View attachment 83029
View attachment 83028

Next steps are to measure the outdoors speaker position, and perhaps get a better idea how good it can be. Then work backwards. The DSP is adding clarity and fixing impulse and timing issues L to R but it also seems to add a layer of audible dullness to the sound. The clarity with the DAC only (playing one channel only) is far greater. So something going on with the combined sound of both channels.

Comments and suggestions are welcomed.

var smoothing is the best to analyse.

not sure how to interpret your data. would be intresting to find out what is causing the remaining cancellation. there should not be much going on regarding standing waves between the walls in you room. Maybe between floor and ceiling? https://mehlau.net/audio/floorbounce/

have you found out the frequencies which make all the glass vibrate?

also for you comined sound issue it would be intresting to see a chart overlay of left and right speaker
 
OP
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Thread Starter #44
var smoothing is the best to analyse.

not sure how to interpret your data. would be intresting to find out what is causing the remaining cancellation. there should not be much going on regarding standing waves between the walls in you room. Maybe between floor and ceiling? https://mehlau.net/audio/floorbounce/

have you found out the frequencies which make all the glass vibrate?

also for you comined sound issue it would be intresting to see a chart overlay of left and right speaker

The big null mode is a height mode. Sadly impossible to correct without subs I think.

Interested to see if I can remove the 300-400 Hz null though, and the treble roll off is pretty sharp after 10kHz, old drivers / crossover caps.



BEFORE WITH VAR SMOOTHING.jpg
AFTER VAR SMOOTHING.jpg



And yes, great idea, I will investigate where the glass is resonant - have not experienced too much brightness, probably due to the HF roll off mentioned.

And yes next time I am measuring I will look at left and right - although I did measure the initial position - see below.

LEFT RIGHT AND BOTH CHANNELS - INITIAL POSITION.jpg
 

dasdoing

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#46
The big null mode is a height mode. Sadly impossible to correct without subs I think.

Interested to see if I can remove the 300-400 Hz null though, and the treble roll off is pretty sharp after 10kHz, old drivers / crossover caps.



View attachment 83058 View attachment 83059


And yes, great idea, I will investigate where the glass is resonant - have not experienced too much brightness, probably due to the HF roll off mentioned.

And yes next time I am measuring I will look at left and right - although I did measure the initial position - see below.

View attachment 83060

I wouldn't care too much for 10dB variations; the best studios will have those.
for treating floor to ceiling issues you can install a ceiling cloud (can be done without too much impact on the visual) between the speakers and LPs.
the sugestion mentioned above to have a look at ETC, is a good one.
HF rolloff is something very comom in treated rooms (and EQing it to flat will produce hurting cymbals and other stuff), and your's is kind of one, since you angled walls deflect the wall reflections
 
OP
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Thread Starter #47
Spectrogram should be limited to 200-250 Hz. Use ETC to find reflections.

Mic calibration file loaded? 90° (e.g. pointing at ceiling) or 0° ?
Yes, using the 90 deg cal file with mic pointing to ceiling.

Will have a look at ETC and the Spectograph based on your tip - thanks.
 
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Thread Starter #48
Spectograms reproduced with better detail.

Before with speakers initially positioned deeper into the vee of the room.

LEFT CH - SETUP 1 - DAC ONLY.jpg
RIGHT CH - SETUP 1 - DAC ONLY.jpg

BOTH CH - SETUP 1 - DAC ONLY.jpg


Speakers then moved out of the vee further, and when measurements improved, room correction with DIRAC was performed. Then I simply tailor the HF and LF portions of the correction to match the speakers natural curves.

BOTH CH - SETUP 2 - DSP FINAL.jpg


This final version - setup 2 - is quite good. Still a small hiccup between 300 and 400 Hz, but the decay times seem much more linear from low to mid frequencies, compared to the initial DAC only measurements.

ETC - what should I be looking for - graphs are quite different? Pre-ringing on the DSP version is very measurable if not audible.

DAC ONLY INITIAL - ETC.jpg
DSP FINAL - ETC.jpg
 
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ezra_s

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#49
Another location that would suite me is the one I mark in red:
IMG_8548.jpg


I also find odd that you and I seem seem to have that low level dip in bass between 50hz and 60hz with 60 to 65hz going up over the desired level is that typical?
 

dasdoing

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#50
Spectograms reproduced with better detail.

Before with speakers initially positioned deeper into the vee of the room.

View attachment 83133 View attachment 83134
View attachment 83135

Speakers then moved out of the vee further, and when measurements improved, room correction with DIRAC was performed. Then I simply tailor the HF and LF portions of the correction to match the speakers natural curves.

View attachment 83136

This final version - setup 2 - is quite good. Still a small hiccup between 300 and 400 Hz, but the decay times seem much more linear from low to mid frequencies, compared to the initial DAC only measurements.

ETC - what should I be looking for - graphs are quite different? Pre-ringing on the DSP version is very measurable if not audible.

View attachment 83138 View attachment 83139

someting is wrong with the ETC graphs. can you atach the mdat?
 
OP
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Thread Starter #51
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#52
ETC: (RFZ is no way near ;))
etc_syd.jpg

Spectrogram, normaliced:
spec_li_syd.jpg

Or use waterfall diagram, 60 dB range (you should measure at least 10 dB louder)
wf_li_syd.jpg

T60M/T30 is high, way to high.
Please add pics of your current setup. I'm suprised ETC is that bad. Bass not EQ, no spurise here.
 
OP
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Thread Starter #53
ETC: (RFZ is no way near ;))
View attachment 83210

Ok, what is RFZ and what is nowhere near? I am new to all this and definitely still learning.



Spectrogram, normaliced:
View attachment 83211

What setting are you using - not wavelet?


Or use waterfall diagram, 60 dB range (you should measure at least 10 dB louder)
View attachment 83212
T60M/T30 is high, way to high.

Ok, so measurements should be peaking at 95dB? And what settings do you have the waterfall diagram on? The valleys look different.


Please add pics of your current setup. I'm suprised ETC is that bad. Bass not EQ, no spurise here.


I have moved everything but the position of speakers was as below;
IMG_1907.jpg

TV was in between speakers but set back closer to the window surface.
IMG_1905.jpg


The blue dot in the centre of the floor is the LP, which is about 1900mm or so direct to each driver.

IMG_1908.jpg

So what do you think? If I move any further out the LP is right up against the rear wall which is on an angle.

I actually want to measure outside to get a baseline for the speaker without reflections, because listening to them out there was subjectively so much better! Any tips for measuring outside?

Another idea I had was to drop them down off the trolleys to change the height mode.
 

RayDunzl

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#54
ETC:

You have a high level for early reflections (-5dB relative to the direct sound), and a very long time for sound to decay (about 600ms)

1600329004396.png


(An example of mine, for comparison - first reflections about -25dB and 300ms settling time)

1600329359636.png




The impulse response shows the time the reflections occur relative to the direct sound at 0ms:

1600329094347.png


(an example of mine for comparison - reflections low in relative level and few in number)

1600329298670.png


So...

Consider my examples something of an extreme - smaller open furnished room, MartinLogan dipoles, and a little deadening beyond the couch and carpet.

You have a nice view, the sound is probably good at low to moderate levels, might sound like an echo box at high levels.

Imaging - I don't know, might be acceptable, might not, depending on what you like.

After the initial reflections, it would seem to be much more diffused (probably good) but still at a high level over time (maybe not so good).

There are suggestions to put it all in a closed room.

I think I'd live with the view and work on it a little.

The reflections surely are the floor and windows and probably the ceiling and bounces from one "wall" to the other.

My supposition would be that the curtains shown do next to nothing sonically.

---

Frequency response and distortion plots look good enough.

1600331433876.png


1600331381254.png


Step response a little ragged:

1600331246969.png
 
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#55
damn... Just seeing the skyline of the CBD gives me thrills and makes me emotional. I miss my Aussie friends and living there so much. Best city in the world. Enjoy your new place ! looks like Bondi Junction, the view is fantastic.
 
OP
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Thread Starter #56
damn... Just seeing the skyline of the CBD gives me thrills and makes me emotional. I miss my Aussie friends and living there so much. Best city in the world. Enjoy your new place ! looks like Bondi Junction, the view is fantastic.
Thank you.

She is a beautiful city! Sounds like you might be back - one day.... ; )
 
OP
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Thread Starter #57
ETC:

You have a high level for early reflections (-5dB relative to the direct sound), and a very long time for sound to decay (about 600ms)

View attachment 83318

(An example of mine, for comparison - first reflections about -25dB and 300ms settling time)

View attachment 83321



The impulse response shows the time the reflections occur relative to the direct sound at 0ms:

View attachment 83319

(an example of mine for comparison - reflections low in relative level and few in number)

View attachment 83320

So...

Consider my examples something of an extreme - smaller open furnished room, MartinLogan dipoles, and a little deadening beyond the couch and carpet.

You have a nice view, the sound is probably good at low to moderate levels, might sound like an echo box at high levels.

Imaging - I don't know, might be acceptable, might not, depending on what you like.

After the initial reflections, it would seem to be much more diffused (probably good).

There are suggestions to put it all in a closed room.

I think I'd live with the view and work on it a little.

The reflections surely are the floor and windows and probably the ceiling and bounces from one "wall" to the other.

My supposition would be that the curtains shown do next to nothing sonically.

Ray, thank you for the response, I now get what MarsianC# was trying to explain - it is pretty crap!

So it rings and is bright, and at high levels is probably fatiguing (have not spent much time listening lately). The reflections have lots to work with and few places to go. I actually have setup in the yellow location at the moment - so will be interesting to measure yellow with all the doors open (removes about 30% of walls / glass).

Curtains are subject of discussion as we are coming into Australian summer when the sun rises at 5am - so perhaps something heavy and thick can be negotiated.

The view is sacred to my partner, she really enjoys the observation spot, so my gear is only allowed into the corner for weekends - hence everything is currently on trolleys.

To be honest, if I can find a reasonable compromise for low levels, 70-80dB peaks, then on those occasions when I want to spend a few hours at +90dB I can take everything out onto the deck and enjoy the real sonic experience minus the room.

The live sound outside was epic - as I might have said once or twice ; )) - looking forward to measuring it.
 
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#58
So what do you think?
Move them as close as possible to the wall and angle them in. Maybe even more than 30°. Absorb ceiling reflections.
Any tips for measuring outside?
Bass response can be measured nearfield (mic very close to center of woofer). Speaker itself with mic at 1 m, absorn floor bounce and gate signal to eliminate reflections (5 ms would be good). Try setting a gate in REW and see what it does.
 

RayDunzl

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#59
Thoughts, suggestions?
Life is full of compromises.

I assume the room was still unfurnished at the time of masurement.

Measure again after it is lived in for a bit, see what changes.
 
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