Simplified REW Setup and Use (USB Mic & HDMI Connection) Including Measurement Techniques and How To Interpret Graphs - Page 369 - AVS Forum
Forum Jump: 
 18Likes
Reply
 
Thread Tools
post #11041 of 11066 Old Yesterday, 10:15 AM
AVS Special Member
 
Alan P's Avatar
 
Join Date: Jan 2003
Location: Rapid City, South Dakota
Posts: 2,076
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 314 Post(s)
Liked: 191
Your MDAT file doesn't have any of the Audyssey ON measurements.

AVR: DENON 2113ci
FL/R: Klipschorn
CC: Klipsch RC64ii
SUR: Polk LS F/X x 4
SUB: PSA XS15 x 4 + MiniDSP 2x4
DISP: Mitsubishi WD-73740
Alan P is online now  
Sponsored Links
Advertisement
 
post #11042 of 11066 Old Yesterday, 10:50 AM
Member
 
Zee-man's Avatar
 
Join Date: Mar 2013
Location: Indy
Posts: 27
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Liked: 10
Quote:
Originally Posted by Alan P View Post
I agree, less peaks for Audyssey to pull down = less distortion + more headroom.

UNLESS, location B doesn't give you enough headroom, then you may be forced to use location A.

Also, the scale is wrong on your graphs. Should be 45-105 on the vertical and 15-200 on the horizontal.

Oh, and really no need to measure so loudly. You could pull down the MV 5 or 10db and still be fine.
I'm a noob at this, but I was concerned about the rather large null at 45Hz in the B location (red graph in the first chart in prev post)? If I understand correctly, placement is the best (maybe only) way to get rid of a null and I figured the fewer the nulls the better since the peaks can be fixed through Audyssey.

My bad on the 300 horiz graph.

Here is the "refined" location A graph that shows the subs w/o aud (red) and with aud (blue). it appears that audyssey only pulled down one peak. Is this acceptable, does that alleviate your concerns about my location A?


Oops - just noticed one of the graphs in my prev post was not quite correct. This is the "refined" location A graph with both subs and mains running with aud. The graph in my prev post showed only the left sub with the mains.


I'm having some issues with volumes when measuring. When I hit the CHECK LEVELS button, sometimes it will say the level is too low but when I run the test, I almost run out of headroom. ??? I need to re-read the REW guide to find out what's wrong - likely a setting on my part.
Zee-man is online now  
post #11043 of 11066 Old Yesterday, 10:57 AM
Member
 
Zee-man's Avatar
 
Join Date: Mar 2013
Location: Indy
Posts: 27
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Liked: 10
Quote:
Originally Posted by Alan P View Post
Your MDAT file doesn't have any of the Audyssey ON measurements.
I linked two mdat files on my post, you must have only got the first one.

FYI - the first mdat shows subs only w/o aud so I could compare the 3 locations. After that test, I assumed location A was better so I level matched again, ran aud, and measured to create the 2nd mdat named 8-19 location A final. It is the latest and greatest.
Zee-man is online now  
post #11044 of 11066 Old Yesterday, 10:59 AM
AVS Special Member
 
AustinJerry's Avatar
 
Join Date: Jan 2003
Location: Austin, Texas
Posts: 7,034
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 379 Post(s)
Liked: 671
Sorry, Alan, my intention is not to pick on you, but your description of the sub distance tweak is oversimplified. It actually consists of two distinct steps. The first step involves measuring the two subs by themselves, and varying their distances to achieve the flattest response, for the sub channel only. Then measure both subs combined with the center speaker. Adjust the distances of both subs by the same amount in order to achieve the flattest response between the combined subs and the center at the crossover point. The sub distance tweak is not guaranteed to produce significant results (if makes very little difference in my setup, for example), but should always be tried to ensure the best results.

And why do you say that the graph scales are incorrect. We have agreed that the vertical scale should show 5dB increments, which it does, and that the horizontal scale should be 15-300Hz, which it is. I believe this is documented in the Guide.

HST, I agree with both you and Jim that the red graph looks to be the best measurement. Next step woul be to see the effect Audyssey has on placement B so we can make a final comparison.
AustinJerry is online now  
post #11045 of 11066 Old Yesterday, 11:08 AM
AVS Special Member
 
AustinJerry's Avatar
 
Join Date: Jan 2003
Location: Austin, Texas
Posts: 7,034
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 379 Post(s)
Liked: 671
Quote:
Originally Posted by Zee-man View Post


I'm having some issues with volumes when measuring. When I hit the CHECK LEVELS button, sometimes it will say the level is too low but when I run the test, I almost run out of headroom. ??? I need to re-read the REW guide to find out what's wrong - likely a setting on my part.
There is nowhere in the Guide that says to hit the Check Levels button. Is that the button on the measurements screen? Ignore it, and just make sure your levels aren't high enough to produce clipping.
Zee-man likes this.
AustinJerry is online now  
post #11046 of 11066 Old Yesterday, 11:08 AM
Member
 
Zee-man's Avatar
 
Join Date: Mar 2013
Location: Indy
Posts: 27
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Liked: 10
Here is the mdat for the latest and greatest test which only shows location A, with and w/o aud. This is my much preferred location so I hope the results are decent. This is the 2nd mdat from my prev post.
https://dl.dropboxusercontent.com/u/...A%20Final.mdat
Zee-man is online now  
post #11047 of 11066 Old Yesterday, 11:10 AM
AVS Special Member
 
Alan P's Avatar
 
Join Date: Jan 2003
Location: Rapid City, South Dakota
Posts: 2,076
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 314 Post(s)
Liked: 191
Quote:
Originally Posted by AustinJerry View Post
Sorry, Alan, my intention is not to pick on you, but your description of the sub distance tweak is oversimplified. It actually consists of two distinct steps. The first step involves measuring the two subs by themselves, and varying their distances to achieve the flattest response, for the sub channel only. Then measure both subs combined with the center speaker. Adjust the distances of both subs by the same amount in order to achieve the flattest response between the combined subs and the center at the crossover point. The sub distance tweak is not guaranteed to produce significant results (if makes very little difference in my setup, for example), but should always be tried to ensure the best results.

And why do you say that the graph scales are incorrect. We have agreed that the vertical scale should show 5dB increments, which it does, and that the horizontal scale should be 15-300Hz, which it is. I believe this is documented in the Guide.

HST, I agree with both you and Jim that the red graph looks to be the best measurement. Next step woul be to see the effect Audyssey has on placement B so we can make a final comparison.
Feel free to pick on me, Jerry. I don't mind at all.

In my defense, I wasn't aware the OP had an AVR that could calibrate dual subs separately. I also never heard that you should perform the tweak with subs+center....I always read it should be sub+FL/R.

If this indeed is the case, I've been doing it wrong for a really long time. However, it has always produced dramatic results around the crossover point in my system.

RE: graph scale. I obviously need to read the revised guide. Sorry about that. I'm just going by this post from kbarnes, and have been using those settings myself for posting graphs since day one.

Again, sorry if I caused any confusion.

AVR: DENON 2113ci
FL/R: Klipschorn
CC: Klipsch RC64ii
SUR: Polk LS F/X x 4
SUB: PSA XS15 x 4 + MiniDSP 2x4
DISP: Mitsubishi WD-73740
Alan P is online now  
post #11048 of 11066 Old Yesterday, 11:12 AM
AVS Special Member
 
Alan P's Avatar
 
Join Date: Jan 2003
Location: Rapid City, South Dakota
Posts: 2,076
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 314 Post(s)
Liked: 191
Quote:
Originally Posted by Zee-man View Post
I'm having some issues with volumes when measuring. When I hit the CHECK LEVELS button, sometimes it will say the level is too low but when I run the test, I almost run out of headroom. ??? I need to re-read the REW guide to find out what's wrong - likely a setting on my part.
Which mic are you using? Are you calibrating the SPL before taking measurements?

AVR: DENON 2113ci
FL/R: Klipschorn
CC: Klipsch RC64ii
SUR: Polk LS F/X x 4
SUB: PSA XS15 x 4 + MiniDSP 2x4
DISP: Mitsubishi WD-73740
Alan P is online now  
post #11049 of 11066 Old Yesterday, 11:15 AM
AVS Special Member
 
Alan P's Avatar
 
Join Date: Jan 2003
Location: Rapid City, South Dakota
Posts: 2,076
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 314 Post(s)
Liked: 191
Quote:
Originally Posted by Zee-man View Post
Here is the mdat for the latest and greatest test which only shows location A, with and w/o aud. This is my much preferred location so I hope the results are decent. This is the 2nd mdat from my prev post.
https://dl.dropboxusercontent.com/u/...A%20Final.mdat
After just a cursory look at the MDAT....if there's a way you could put both subs in the "R" position, I think you would get a much flatter response.

Is DynEQ off when you are measuring?

Also, don't forget to try the distance tweak (as Jerry described how to do above ).

AVR: DENON 2113ci
FL/R: Klipschorn
CC: Klipsch RC64ii
SUR: Polk LS F/X x 4
SUB: PSA XS15 x 4 + MiniDSP 2x4
DISP: Mitsubishi WD-73740
Alan P is online now  
post #11050 of 11066 Old Yesterday, 11:16 AM
AVS Special Member
 
AustinJerry's Avatar
 
Join Date: Jan 2003
Location: Austin, Texas
Posts: 7,034
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 379 Post(s)
Liked: 671
No harm done, Alan. The time-honored Sub Distance Tweak can be viewed here. I believe KBarnes authored the actual document, but the procedure is really Craig John's and Mark Seaton's.

If the OP doesn't have dual sub channels, then of course the subs should be equidistant, and the procedure needs to be modified accordingly.

Edit: With regards to using the center vs L+R, the reason is that the center is much more important for movie content, so getting the splice correct with the center provides the most benefit. If you then check the splice with the L+R, it is usually optimized as well. If not, stick with optimizing the center+subs.

Last edited by AustinJerry; Yesterday at 11:19 AM.
AustinJerry is online now  
post #11051 of 11066 Old Yesterday, 11:48 AM
AVS Special Member
 
Alan P's Avatar
 
Join Date: Jan 2003
Location: Rapid City, South Dakota
Posts: 2,076
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 314 Post(s)
Liked: 191
Thanks Jerry!

What do you do if the splice with the L/R is NOT good after your optimize the splice with the center? Should you adjust the distance of the L/R speakers?? I'm guessing no.

AVR: DENON 2113ci
FL/R: Klipschorn
CC: Klipsch RC64ii
SUR: Polk LS F/X x 4
SUB: PSA XS15 x 4 + MiniDSP 2x4
DISP: Mitsubishi WD-73740
Alan P is online now  
post #11052 of 11066 Old Yesterday, 12:26 PM
AVS Special Member
 
AustinJerry's Avatar
 
Join Date: Jan 2003
Location: Austin, Texas
Posts: 7,034
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 379 Post(s)
Liked: 671
Never adjust the distances of the main speakers. Any difference is likely to be small, based on my experience. If the difference were significant, then I would let my ears be the judge. Don't know what other options there might be.
AustinJerry is online now  
post #11053 of 11066 Old Yesterday, 06:10 PM
Advanced Member
 
artur9's Avatar
 
Join Date: Mar 2013
Location: near philly
Posts: 703
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 34 Post(s)
Liked: 40
I got another sub at auction and my new UMIK-1 to replace a failed UMM6. I'd also moved 2 of my subs to the front wall in preparation for trying flanking subs with a higher crossover setting.

After taking the below measurements I noticed the little foam cover for the mic. Do I have to use that?

After some fiddling I got the following results. Despite the labels the L+R were on the whole time.

The question I have is this. I did a 15-300Hz sweep that looked good but then when I did a 15-20K Hz sweep it looked terrible. I repeated the bass-only sweep and that looked the same as the red sweep again.

No smoothing, no DSP other than the one parametric setting on the Dayton SA1000 knock-off (which wasn't very effective, BTW).

Green is before any adjustments, red is with everything dialed in, then blue is full frequency sweep. Any idea why the blue looks different from the red?
Attached Images
File Type: jpg umik-1 measures.jpg (94.4 KB, 63 views)
artur9 is offline  
post #11054 of 11066 Old Yesterday, 06:25 PM
AVS Special Member
 
AustinJerry's Avatar
 
Join Date: Jan 2003
Location: Austin, Texas
Posts: 7,034
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 379 Post(s)
Liked: 671
The part of the measurement below the crossover point should look about the same whether you are measuring to 300Hz, or whether it is a full sweep. May I assume that you are running the mains as "small" with a crossover? What is the crossover value?

The level for the full sweep measurement looks low. Any idea why it would be so much lower?

And the little foam thing can be used or not--it doesn't make a difference. It is acoustically transparent.

Edit: BTW, what do you mean, "dialed in".

Last edited by AustinJerry; Yesterday at 06:28 PM.
AustinJerry is online now  
post #11055 of 11066 Old Yesterday, 06:30 PM
Advanced Member
 
artur9's Avatar
 
Join Date: Mar 2013
Location: near philly
Posts: 703
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 34 Post(s)
Liked: 40
The crossover is set to 120Hz.

That whole blue measurement is strange because I touched nothing other than to change the sweep to 20KHz. Then I changed it back to 300Hz and the measurement was identical to the red line again.

By "dialed in" I meant I was happy with the measurements for now.
artur9 is offline  
post #11056 of 11066 Old Yesterday, 09:08 PM
AVS Special Member
 
AustinJerry's Avatar
 
Join Date: Jan 2003
Location: Austin, Texas
Posts: 7,034
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 379 Post(s)
Liked: 671
There shouldn't be any difference. Here is a measurement from my system:





The measurements are essentially identical up to approx. 60Hz, when the influence of the center channel alters the response.
AustinJerry is online now  
post #11057 of 11066 Old Today, 07:56 AM
Advanced Member
 
HDgaming42's Avatar
 
Join Date: Sep 2006
Location: Alberta, Canada
Posts: 516
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 30 Post(s)
Liked: 11
Back for more...

Hi guys,

I finally moved my sub to the back of the room following all the advice I got way back here, and I completed and placed my bass traps. Here are my results.

My Room Sim was unusual as it suggested the most ideal MLP to be in the dead center of the room. This was it's prediction:



My result (didn't save it) didn't look anything like that (even a 1" movement in Room Sim seems to destroy this particular prediction. I found the ideal sub placement and MLP to be with the MLP 105" into the room, center width.

Room Sim's version of this placement:



This is a bit jumbled, but stick with me if you will. Here is a comparison of no treatment (red) to two full height corner bass traps up front (green) with two tweaks*. More on that later.



Waterfalls:



purple instead of red for some reason--but corresponds to the All SPL above it.


After spending nearly a month's worth of "free time" (which wasn't a lot TBH) I guess I was hoping for a flatter response.

Here's what I found interesting and could use some advice on (actually, I'm soliciting all advice on anything you see here!!).

I have a set of double, solid core doors with air-tight gaskets to enter the room. It seems like that is messing with my response!



By opening the interior door I drop a peak by a number of dB, and raise a null. The door cavity is airtight (double wall construction all around). I've read that drilling holes between the doors to provide airflow into the wall cavities can help...but now I can't dig up that advice. I was worried this would short-circuit my soundproofing. Thoughts? Advice? Also of note, my rack's plexiglass door was creating havok, and I removed it to get to the point you see as "best result", no plexi-door and one door open.

Here's where I'm at utilizing best placement, no plexi-glass door and one door open. Also, two 7ft tall bass traps (corner chunk Roxul Safe N Sound) in the front two corners.



Where do I go from here?
Room Sim doesn't seem to be able to come up with a 2nd sub fix for this room. The back wall is problematic as it has those double doors, and a cubby for the equipment rack. There is really only four feet of treatable area on the back wall.

I'm open to all suggestions--really interested in your thoughts on drilling holes (how big, how many?) between the casing of the two double doors. Would love to be able to keep my (expensive!) plexi door for my rack too...

Feeling...defeated.

PS I tested pulling the traps away from the wall (they're free-standing) in 1" increments. I could see no benefit going beyond 1". I went all the way to 8", which was the maximum feasible in my room. My traps are faced with 6mil poly.
Attached Images
File Type: png best result spl.png (89.2 KB, 1 views)
File Type: png compare double doors.png (132.0 KB, 1 views)
File Type: png room calc of what worked.PNG (93.5 KB, 1 views)
File Type: png no treatment waterfall.png (547.8 KB, 1 views)
File Type: png best result waterfall.png (531.4 KB, 2 views)
File Type: png treatment comparison.png (146.4 KB, 1 views)

Last edited by HDgaming42; Today at 07:59 AM.
HDgaming42 is online now  
post #11058 of 11066 Old Today, 08:18 AM
Senior Member
 
frankie2075's Avatar
 
Join Date: Mar 2011
Location: BROOKLYN, NY
Posts: 399
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 26 Post(s)
Liked: 15
Whats a good mic to buy to use with REW? Link to it if possible thanks.
frankie2075 is online now  
post #11059 of 11066 Old Today, 08:43 AM
Advanced Member
 
HDgaming42's Avatar
 
Join Date: Sep 2006
Location: Alberta, Canada
Posts: 516
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 30 Post(s)
Liked: 11
Quote:
Originally Posted by frankie2075 View Post
Whats a good mic to buy to use with REW? Link to it if possible thanks.
For USB mics it usually ends up coming down to two suggestions, either the UMIK-1, or the UMM-6.

There are many threads about these mics. Here's one.
HDgaming42 is online now  
post #11060 of 11066 Old Today, 09:51 AM
Senior Member
 
frankie2075's Avatar
 
Join Date: Mar 2011
Location: BROOKLYN, NY
Posts: 399
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 26 Post(s)
Liked: 15
Quote:
Originally Posted by HDgaming42 View Post
For USB mics it usually ends up coming down to two suggestions, either the UMIK-1, or the UMM-6.

There are many threads about these mics. Here's one.
Thanks.
frankie2075 is online now  
post #11061 of 11066 Old Today, 09:56 AM
Advanced Member
 
HDgaming42's Avatar
 
Join Date: Sep 2006
Location: Alberta, Canada
Posts: 516
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 30 Post(s)
Liked: 11
Quote:
Originally Posted by frankie2075 View Post
Thanks.
I bought the UMIK-1, but if I did it again I would have purchased from a vendor that provides a calibration file for orienting the mic directly at the ceiling. The cost is not much higher (if at all) and I would now like to have that capability...
HDgaming42 is online now  
post #11062 of 11066 Old Today, 10:30 AM
Senior Member
 
frankie2075's Avatar
 
Join Date: Mar 2011
Location: BROOKLYN, NY
Posts: 399
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 26 Post(s)
Liked: 15
Quote:
Originally Posted by HDgaming42 View Post
I bought the UMIK-1, but if I did it again I would have purchased from a vendor that provides a calibration file for orienting the mic directly at the ceiling. The cost is not much higher (if at all) and I would now like to have that capability...
Seems like you can download the calibration file if you type in your serial number on minidsp website. I already have a stand for the mic if i get it. I came with my auddessey pro calibration kit.
frankie2075 is online now  
post #11063 of 11066 Old Today, 11:07 AM
Senior Member
 
AV_mike's Avatar
 
Join Date: May 2009
Posts: 268
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Liked: 37
^^^^^^^^^
The downloadable calibration file (from Dayton, or MiniDSP) is for a single orientation (pointed at the sound source, 0 degrees)
Cross Spectrum Labs will provide multiple orientation cal files with their products, including the Narrow Band, 90 degree file that is required for optimum use with REW.
Regards, Mike.
AV_mike is online now  
post #11064 of 11066 Old Today, 11:31 AM
Advanced Member
 
RayDunzl's Avatar
 
Join Date: Sep 2013
Location: Tampa, Florida
Posts: 657
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 223 Post(s)
Liked: 202
Quote:
Originally Posted by AV_mike View Post
^^^^^^^^^
The downloadable calibration file (from Dayton, or MiniDSP) is for a single orientation (pointed at the sound source, 0 degrees)
Cross Spectrum Labs will provide multiple orientation cal files with their products, including the Narrow Band, 90 degree file that is required for optimum use with REW.
Regards, Mike.
Looking at sample cross spectrum files, the difference in the response curves for 0,45,90 degrees occurs at the high frequencies.

Sample UMIK

Sample UMM6

Low frequencies (sub woofer range and higher) look the same.

However, they say:

"Our own microphone measurements indicate that the factory calibration data included with the mics may not be representative of the UMM-6's individual performance."

They don't add that type of qualification to the UMIK-1 page.

I'll be back later...


equitech 1.5RQ > digits > miniDSP > behringer > benchmark > krell pre and monoblocks > reQuest

Last edited by RayDunzl; Today at 11:45 AM.
RayDunzl is online now  
post #11065 of 11066 Old Today, 11:53 AM
Advanced Member
 
HDgaming42's Avatar
 
Join Date: Sep 2006
Location: Alberta, Canada
Posts: 516
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 30 Post(s)
Liked: 11
Quote:
Originally Posted by RayDunzl View Post
Looking at sample cross spectrum files, the difference in the response curves for 0,45,90 degrees occurs at the high frequencies.

Sample UMIK

Sample UMM6

Low frequencies (sub woofer range and higher) look the same.

However, they say:

"Our own microphone measurements indicate that the factory calibration data included with the mics may not be representative of the UMM-6's individual performance."

They don't add that type of qualification to the UMIK-1 page.
You just made my day! I had assumed I would not be able to trust a 90 degree orientation, but now it appears that I can (for non-HF use).
HDgaming42 is online now  
post #11066 of 11066 Old Today, 11:58 AM
AVS Special Member
 
AustinJerry's Avatar
 
Join Date: Jan 2003
Location: Austin, Texas
Posts: 7,034
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 379 Post(s)
Liked: 671
Quote:
Originally Posted by frankie2075 View Post
Whats a good mic to buy to use with REW? Link to it if possible thanks.
You should read the guide link in my sig--it has all the info on the mics.
AustinJerry is online now  
Reply Audio theory, Setup and Chat

Tags
Dayton , Dayton Audio , Room Equilizer Wizard Rew

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off