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Simplified REW Setup and Use (USB Mic & HDMI Connection) Including Measurement Techniques and How... - Page 177

post #5281 of 9619
Quote:
Originally Posted by bao01 View Post
 
Quote:
Originally Posted by jkasanic View Post

The convention we've been using is to look at the modal region "unsmoothed".  1/48th shouldn't be a huge difference (at least it's not with my plots).  The below 30Hz ringing will be very difficult to eliminate with treatments as you'd need VERY thick absorbtion down there to have any impact...not "impossible" as I've been told but very difficult.  In any case, you're not alone and most have said THWI and moved on to reflections at that point.

I just did a 1/48 SPL because i was dong a waterfall and 101 says use 1/48 for waterfall - normally i would do unsmoothed for bass SPL.

thanks - it is good to know it is not an unusually bad waterfall.

i am near the THWI stage - 130 lb subs are a PAIN - even with the stupid "magic" sliders on carpet

 

As I recall, your MLP is not centered along your screen wall (isn't it shifted to the right side of the room if you're sitting in your MLP)?  Did you ever try moving your soundstage so that it is centered along your screen wall and then putting your subs at the 1/4 and 3/4 pts along that wall?  If I remember your room dimensions correctly (as well as the advice you've already been given in this thread), this should smooth out your natural response and then perhaps your Audyssey result will look a little different (in the frequency domain that is).  Again, if you want to eliminate the ringing below 30Hz be prepared to invest a lot more effort than sliding your subs around...

Gear mentioned in this thread:

post #5282 of 9619
Ok, I'll post graphs soon. The reality that my room sucks and I will live with for awhile is setting in. That basically I will choose what sounds the best at this point and live with it. I tried about 7 different two sub combinations...
post #5283 of 9619
Ok. I might rebut my last comment. I noticed on my last couple measurements the sub to the left of the tv I had forgot to flip the power switch after I had moved it. I have to be completely honest though. I did not adjust the distance and I still don't quite know what that hurts. I put a title on each graph describing room position of each sub.

This picture describes what I mean by "right wall". Basically it is a few feet forward of the couch and on the right wall.


Here are the graphs. I ran a 5 mic Audyssey calibration after what I thought was the best graph. So all are raw pre Audyssey until the last one.







post #5284 of 9619
Quote:
Originally Posted by jlpowell84 View Post

The reality that my room sucks and I will live with for awhile is setting in.
Doesn't have to be that way. Your room is currently laid out with the right speaker corner loaded and the left speaker in the open, giving you a lopsided soundstage with very different bass response from each of your front speakers. On top of that, the entire left side wall of the room is missing, acting like a giant absorber, while the opposite side wall is completely reflective.

The solution is to turn your set-up 90 degrees.

Before you reflexively dismiss the idea, keep in mind that you'll be facing the TV whether on your exercise machine or standing in the kitchen. For 11.5 feet on either side of you, you'll have completely symmetrical side walls, for excellent left-vs-right consistency in the soundstage. If you use your system to listen to music, it will be the single biggest improvement you can make.
post #5285 of 9619
Quote:
Originally Posted by bao01 View Post



 

That's much better - I mean worse :)  Much more like what I expected to see having seen photos of the room.

post #5286 of 9619
Quote:
Originally Posted by jlpowell84 View Post

Ok, I'll post graphs soon. The reality that my room sucks and I will live with for awhile is setting in. That basically I will choose what sounds the best at this point and live with it. I tried about 7 different two sub combinations...

 

Sanjay is the PlaceMeister and I think you should carefully consider his advice above (rotating the room). As things stand, you will probably never get a totally satisfactory result.

post #5287 of 9619
Quote:
Originally Posted by jlpowell84 View Post

This picture describes what I mean by "right wall". Basically it is a few feet forward of the couch and on the right wall.

 

This might be nothing but if the orientation of your mic shown in the picture is how you did your measurements then I should point out that we typically orient the mic in the vertical direction (tip pointing up) and use the 90 degree narrow band calibration file.  I don't recall which mic you have and whether or not it was calibrated by CSL so you might only have a zero degree cal file?  If that's the case, then I'm not sure if it's better to use the cal file and change the mic orientation or not.  I'm sure others will chime in.

post #5288 of 9619
Quote:
Originally Posted by jkasanic View Post

This might be nothing but if the orientation of your mic shown in the picture is how you did your measurements then I should point out that we typically orient the mic in the vertical direction (tip pointing up) and use the 90 degree narrow band calibration file.  I don't recall which mic you have and whether or not it was calibrated by CSL so you might only have a zero degree cal file?  If that's the case, then I'm not sure if it's better to use the cal file and change the mic orientation or not.  I'm sure others will chime in.

Agree 100%. Nice catch. A proper mic orientation could change the measurements completely. Time to move the subs again! eek.gif
post #5289 of 9619
Quote:
Originally Posted by sdurani View Post

Doesn't have to be that way. Your room is currently laid out with the right speaker corner loaded and the left speaker in the open, giving you a lopsided soundstage with very different bass response from each of your front speakers. On top of that, the entire left side wall of the room is missing, acting like a giant absorber, while the opposite side wall is completely reflective.

The solution is to turn your set-up 90 degrees.

Before you reflexively dismiss the idea, keep in mind that you'll be facing the TV whether on your exercise machine or standing in the kitchen. For 11.5 feet on either side of you, you'll have completely symmetrical side walls, for excellent left-vs-right consistency in the soundstage. If you use your system to listen to music, it will be the single biggest improvement you can make.

I am not opposed to rotating the room at all. Best would be to have the tv center essentially where I had that sub right?
Quote:
Originally Posted by jkasanic View Post

This might be nothing but if the orientation of your mic shown in the picture is how you did your measurements then I should point out that we typically orient the mic in the vertical direction (tip pointing up) and use the 90 degree narrow band calibration file.  I don't recall which mic you have and whether or not it was calibrated by CSL so you might only have a zero degree cal file?  If that's the case, then I'm not sure if it's better to use the cal file and change the mic orientation or not.  I'm sure others will chime in.

I did have the mic horizontal pointing. I didn't realize it made a difference. I have the UMM 6 and have the CSL calibration for it loaded into REW.

I really like the idea of turning the room actually. Symmetrical walls and my seating in relation to the rear wall back by the exercise machine and table look good. I would be sitting right in the middle basically and of course have even walls on either side.

What is the 90 degree calibration file?
post #5290 of 9619
^
Mic orientation doesn't create any differences at low frequencies. I'm more concerned with the mic position. You did move it to the listening position for your measurements?
post #5291 of 9619
I have used a UMIK-1 successfully over the last few months.

I have a new Cross Spectrum UMM-6 that I'm connecting via USB. It shows up in the REW preferences window, where I select it.

But, I get no reading during measurement.

Advice?
post #5292 of 9619
Quote:
Originally Posted by AustinJerry View Post

Agree 100%. Nice catch. A proper mic orientation could change the measurements completely. Time to move the subs again! eek.gif

Agh man! I really like this hobby but there is an element that gives a tedious reaction to me!!! I am going to rotate the room anyway. I can see the above points that it will provide a much better, even room. And allow the seating to be middle of the room.

Quote:
Originally Posted by markus767 View Post

^
Mic orientation doesn't create any differences at low frequencies. I'm more concerned with the mic position. You did move it to the listening position for your measurements?

Yes that pic was during cleanup. I had it horizontally pointing from the side of the couch for some and horizontally pointing from behind the couch towards the tv for some.


Can someone clarify how I should have the mic pointing? I can always call Herb at CSL too
post #5293 of 9619
^
For diffuse field measurements the mic should point upwards and the calibration for that orientation should be loaded into REW. At low frequencies the orientation doesn't matter.
post #5294 of 9619
Quote:
Originally Posted by jkasanic View Post

As I recall, your MLP is not centered along your screen wall (isn't it shifted to the right side of the room if you're sitting in your MLP)?  Did you ever try moving your soundstage so that it is centered along your screen wall and then putting your subs at the 1/4 and 3/4 pts along that wall?  If I remember your room dimensions correctly (as well as the advice you've already been given in this thread), this should smooth out your natural response and then perhaps your Audyssey result will look a little different (in the frequency domain that is).  Again, if you want to eliminate the ringing below 30Hz be prepared to invest a lot more effort than sliding your subs around...

Wow - you have a really good memory.
You are exactly right.
The room is 28.4 ft x 22.2 ft and the TV and main spkrs are along one of the 28.4 walls but offset to the right by 4ft.
The center of TV and MLP are 10.2 ft from right wall instead of 14.2 feet from right wall.
I have not yet tried moving the entire system 4 ft to the left like Feri, Sanjay and others have suggested.
I will try that soon.

What i did do is move the two subs all along the 28.4 ft front wall - i tried all sorts of combinations, including 1/4 and 3/4.
My goal at that time was to see if 66 Hz dip would go away and it did not, no matter what.
I was only looking at SPL graph only, not waterfall.

But i need to redo the tests because i was not methodical and have a feeling i mucked some of the measurements up.
I never adjusted sub distances in the prepro as i was moving/graphing.

After futzing with front wall, i started moving the right sub all along the rear 28.4 ft wall and got best results there - i will post a diagram of best result.

I just care about MLP but if you care about two or more seats, all of these web sites indicate mid point of opposite walls is best which is sort of where i am now.

http://www.harman.com/EN-US/OurCompany/Innovation/Documents/White%20Papers/multsubs.pdf
http://www.aperionaudio.com/blog/dual-subwoofers-for-your-home-theater
http://www.audioholics.com/subwoofer-setup/subwoofer-placement-the-place-for-bass-part-1/subwoofer-placement-the-place-for-bass-part-1-page-6
http://forum.blu-ray.com/showthread.php?t=48286
http://www.bgcorp.com/PDFs/Better%20bass%20through%20multiple%20subwoofers.pdf
Edited by bao01 - 10/15/13 at 8:18am
post #5295 of 9619
Quote:
Originally Posted by kbarnes701 View Post

That's much better - I mean worse smile.gif  Much more like what I expected to see having seen photos of the room.

Can you post your waterfall?
Edited by bao01 - 10/15/13 at 8:46am
post #5296 of 9619
Quote:
Originally Posted by jlpowell84 View Post


Agh man! I really like this hobby but there is an element that gives a tedious reaction to me!!! I am going to rotate the room anyway. I can see the above points that it will provide a much better, even room. And allow the seating to be middle of the room.
Yes that pic was during cleanup. I had it horizontally pointing from the side of the couch for some and horizontally pointing from behind the couch towards the tv for some.


Can someone clarify how I should have the mic pointing? I can always call Herb at CSL too

 

 Follow Markus' advice for mic pointing.  Use the highlighted calibration file:

 

 

I think Sanjay's advice to rotate the room is excellent, and predict you will like the layout and audio quality much better.  Looking forward to some new measurements!  And BTW, welcome to the rabbit hole--there are a number of us who have moved subs, speakers, and furniture quite a few times.  Trust me, you will be rewarded for your efforts!  :)

post #5297 of 9619
Quote:
Originally Posted by markus767 View Post

^
For diffuse field measurements the mic should point upwards and the calibration for that orientation should be loaded into REW. At low frequencies the orientation doesn't matter.

Ok I understand the lower frequencies not mattering much as the highs. I uploaded a calibration file for my mic that was tied to the serial number. After I received it I went to CSL site entered my serial number and they gave me a download file. Does this file indicate which way I should point it or is there another file I need?
post #5298 of 9619
Quote:
Originally Posted by bao01 View Post


Can you post yours?

 

Evidently Keith doesn't have a flash attachment for his camera.  He keeps posting dark rectangles as his pics...   ;)

post #5299 of 9619
Quote:
Originally Posted by jlpowell84 View Post


Ok I understand the lower frequencies not mattering much as the highs. I uploaded a calibration file for my mic that was tied to the serial number. After I received it I went to CSL site entered my serial number and they gave me a download file. Does this file indicate which way I should point it or is there another file I need?

 

I don't understand.  If you purchased the UMM-6 from CSL, it should have come with a thumb drive with custom calibration files on it.

post #5300 of 9619
When the microphone is pointed toward the ceiling, the direct sounds coming from the speakers come at about 90 degrees off the microphone axis. So you need the 90 degree calibration file.
post #5301 of 9619
Quote:
Originally Posted by jlpowell84 View Post

Here are the graphs. I ran a 5 mic Audyssey calibration after what I thought was the best graph. So all are raw pre Audyssey until the last one.


Except at the end (200 Hz) that looks like +/- 7 dB which seems pretty good for unsmoothed.
I think the 200 Hz dip is quite narrow so maybe not audible. Not sure what is causing such a deep dip.
post #5302 of 9619
Quote:
Originally Posted by AustinJerry View Post

 Follow Markus' advice for mic pointing.  Use the highlighted calibration file:




I think Sanjay's advice to rotate the room is excellent, and predict you will like the layout and audio quality much better.  Looking forward to some new measurements!  And BTW, welcome to the rabbit hole--there are a number of us who have moved subs, speakers, and furniture quite a few times.  Trust me, you will be rewarded for your efforts!  smile.gif

Ok, thanks! I am assuming by your pic is one of a REW menu where you select mic orientation? Do we use pointing straight up for most of measurements? Better stated, and perhaps in your guide in which I didn't make it all the way through, is there a list of how we should have the mic pointed for each style of measurement?
post #5303 of 9619
Quote:
Originally Posted by AustinJerry View Post

I don't understand.  If you purchased the UMM-6 from CSL, it should have come with a thumb drive with custom calibration files on it.

Oh!!!! I got it Jerry! Really sorry I didn't know it had calibration files on it!!!

I understand all now! I will double check the guide as far as where to load this file. I'm sure it's quite easy as the REW menus seem user friendly wink.gif
post #5304 of 9619
Quote:
Originally Posted by bao01 View Post

Except at the end (200 Hz) that looks like +/- 7 dB which seems pretty good for unsmoothed.
I think the 200 Hz dip is quite narrow so maybe not audible. Not sure what is causing such a deep dip.

Measure at more than just a single point and you'll get hints what is causing the dip...
Also look at the excess group delay: http://www.hometheatershack.com/roomeq/wizardhelpv5/help_en-GB/html/minimumphase.html
Edited by markus767 - 10/15/13 at 9:02am
post #5305 of 9619
Quote:
Originally Posted by bao01 View Post
 
Quote:
Originally Posted by kbarnes701 View Post

That's much better - I mean worse smile.gif  Much more like what I expected to see having seen photos of the room.

Can you post your waterfall?

 

I  don't have a current one. Here is the last one - I have made minimal changes to the room since this one. This one is DEQ off but the subs are in Pgm 1 mode not Pgm2. So currently the bass will be a little flatter down to the bottom - although this will also have a negative effect on the ringing. I don't have a current waterfall because I had a problem with my HDMI after installing the PJ and it wasn't passing audio. I have fixed that now but haven't gotten around to re-measuring.

 

post #5306 of 9619
Quote:
Originally Posted by AustinJerry View Post
 
Quote:
Originally Posted by bao01 View Post


Can you post yours?

 

Evidently Keith doesn't have a flash attachment for his camera.  He keeps posting dark rectangles as his pics...   ;)

 

I do have a very nice Canon flash gun, but when I use flash the HT room doesn't look anything like the 'real' room :)

post #5307 of 9619
Quote:
Originally Posted by jlpowell84 View Post

Quote:
Originally Posted by AustinJerry View Post

I don't understand.  If you purchased the UMM-6 from CSL, it should have come with a thumb drive with custom calibration files on it.

Oh!!!! I got it Jerry! Really sorry I didn't know it had calibration files on it!!!

I understand all now! I will double check the guide as far as where to load this file. I'm sure it's quite easy as the REW menus seem user friendly wink.gif

Dude...read the guide!! It will save you all the time you've "wasted". It's in the preferences screen of REW. There's even a screen shot in the guide so just look at the pics!!
post #5308 of 9619
frown.gif my apologies. I seen several things in there not pertaining to me since I am on a Mac. I followed the sound flower/Mac instructions instructions that are linked off Jerry's guide. I will not make another post until I have smile.gif. I had a feeling...
post #5309 of 9619
Quote:
Originally Posted by jkasanic View Post
 
 
Dude...read the guide!! It will save you all the time you've "wasted". It's in the preferences screen of REW. There's even a screen shot in the guide so just look at the pics!!

 

+1

post #5310 of 9619
Quote:
Originally Posted by kbarnes701 View Post

I  don't have a current one. Here is the last one - I have made minimal changes to the room since this one. This one is DEQ off but the subs are in Pgm 1 mode not Pgm2. So currently the bass will be a little flatter down to the bottom - although this will also have a negative effect on the ringing. I don't have a current waterfall because I had a problem with my HDMI after installing the PJ and it wasn't passing audio. I have fixed that now but haven't gotten around to re-measuring.



Thanks.

You have a 45 dB floor. 101 guide says use 50 floor and in Aud thread you suggested 40 floor is convention for this thread.
Arggghhhh confused.gif

Also, are you using 0, 90, 150 for X, Y, Z? It looks like we are looking at it from left to right instead of head on like mine?

I have only posted a 40 floor with 450 msec time range and a 50 floor with 600 msec time range. But your 20 - 30 Hz is better than either of those.
So how did you do it without huge traps in room confused.gif

EDIT: I guess every room is different and it's kind of silly for me to try compare different rooms so never mind.

EDIT: It looks like you are 20 - 300 Hz +/- 7 dB with 1/48 smoothing?
Edited by bao01 - 10/15/13 at 10:53am
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