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post #4531 of 9491
Quote:

Originally Posted by AustinJerry View Post
 

Is it possible that the subs are exciting that mode too much?  Any advice would be appreciated.

 

Do you have a measurement of just the 2 front subs (with and w/o Audyssey)?  Just guessing that maybe you could check this measurement against Keith's hypothesis of the change in MLP?  Seems like the conundrum of measuring for multiple seats or just the MLP in terms of what is actually going on in the rest of the "listening space" with your old MLP?!

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post #4532 of 9491
Quote:
Originally Posted by AustinJerry View Post

Sanjay, the new MLP is at 31% of the room depth, measured from the back wall.  I have included my most recent layout below.  The front subs are at the 1/4 and 3/4 marks of the room width, which has a 58Hz mode.  Is it possible that the subs are exciting that mode too much?  Any advice would be appreciated.
Wish I had some good advice, but nothing about the change jumps out at me. Did you change listener height by any chance (new chair or sofa maybe)? I ask because you have 57Hz height mode (which could easily be mistaken for your 58Hz width mode).

If you're willing, run just your 4 subs (without Audyssey) and do a few measurements along the centre line of your room (a couple of measurements in 1-foot increments behind the listening position and the same forward of the listening position).

My only concern with an Audyssey-off measurement is that the distance settings from your last Audyssey cal will still have an effect on your subs, the same way speaker/sub blend can be affected by distance settings (even with Audyssey equalization off).
post #4533 of 9491

Thanks for looking at this, Sanjay.  I'm using the same chair, with the same ear-height (35").

 

I could easily take the measurements you suggested, but I would also be concerned with their validity because of the delay and trim settings.  I have also thought about moving the front two subs in small increments, either towards each other, or away from each other (harder to do because of the equipment rack).  After each small move, I could run a quick 3-point calibration and measure the results.  Tedious, but the alternative would be to move everything back the way it was, which would be admitting defeat.  Besides, in my experience, even though you think things are back the way they were, there is no guarantee that everything is indeed as it was...

post #4534 of 9491
Quote:
Originally Posted by jkasanic View Post
 

 

Do you have a measurement of just the 2 front subs (with and w/o Audyssey)?  Just guessing that maybe you could check this measurement against Keith's hypothesis of the change in MLP?  Seems like the conundrum of measuring for multiple seats or just the MLP in terms of what is actually going on in the rest of the "listening space" with your old MLP?!

 

 

I do have these measurements, but, unfortunately, they don't shed any light on what might be happening.

post #4535 of 9491
Quote:
Originally Posted by AustinJerry View Post

Quote:
Originally Posted by jkasanic View Post

 

Do you have a measurement of just the 2 front subs (with and w/o Audyssey)?  Just guessing that maybe you could check this measurement against Keith's hypothesis of the change in MLP?  Seems like the conundrum of measuring for multiple seats or just the MLP in terms of what is actually going on in the rest of the "listening space" with your old MLP?!


I do have these measurements, but, unfortunately, they don't shed any light on what might be happening.

So does this mean that the measurements for the front two subs are similar at both the old and new MLP in the 58 Hz region?
post #4536 of 9491

Looking at my last six calibrations, there seems to be more variability in the results than I would like to see.  For example, here are the last two (blue is current, red is previous):

 

 

IMO, above 80Hz, the current (blue) line looks significantly better.  The only difference between the two is the movement of the MLP forward.

 

So, I am inclined to continue researching the cause of the 58Hz peak, rather than reverting to the old MLP position.  Besides, what impact will the 58Hz problem have in the short term?  It shouldn't affect dialog.  According to the frequency chart we often refer to, I might be impacting the tuba, the bass, and the kick drum.  In the limited listening over the last several days, I haven't been aware of any glaring audio issues.

post #4537 of 9491
Quote:
Originally Posted by jkasanic View Post


So does this mean that the measurements for the front two subs are similar at both the old and new MLP in the 58 Hz region?

 

 

Here they are:

 

 

 

The two graphs actually look pretty similar, and both are ugly.  Remember, it's when the other two subs are blended in that the response flattens out.

post #4538 of 9491
I see what you mean but it is at least curious to see the shift in the peak, no? It seems if you could improve this response that it might improve your overall combined response. Have you tried modifying these two sub locations in small increments?
post #4539 of 9491
Code:
Quote:
Originally Posted by jkasanic View Post

I see what you mean but it is at least curious to see the shift in the peak, no? It seems if you could improve this response that it might improve your overall combined response. Have you tried modifying these two sub locations in small increments?

That is my plan. But it is tedious. Move subs a small distance. Measure with Audyssey off. If improved, run an abbreviated calibration to see if improvement sticks. Rinse. Repeat.
post #4540 of 9491
I'm reading the manual and in the section for Waterfall it says to set speaker output to L/R/Sub. How do I do that through an HDMI?

My only options are 1 through 8 (where 1 is left, 4 is subs). Going through ASIO driver.
post #4541 of 9491

 

Quote:
Originally Posted by shpitz View Post

I'm reading the manual and in the section for Waterfall it says to set speaker output to L/R/Sub. How do I do that through an HDMI?

My only options are 1 through 8 (where 1 is left, 4 is subs). Going through ASIO driver.

 

If you want to measure R + L + Subs, you need Channel 1 in the left hand dropdown box and Channel 2 in the right hand dropdown box. The subs will play by default if you are using bass management.  See image above.

post #4542 of 9491
KB to the rescue! Thanks!

Is it possible to output from all channels at once through HDMI?
post #4543 of 9491
Quote:
Originally Posted by shpitz View Post

KB to the rescue! Thanks!

Is it possible to output from all channels at once through HDMI?

De nada,

 

No - you can choose any two with or without subs, or subs on their own.  If you want satellites without subs you need to physically turn off or disconnect the subs. If you want subs alone, you need to select Channel 4 in the Output box. 

post #4544 of 9491
Quote:
Originally Posted by kbarnes701 View Post

De nada,

No - you can choose any two with or without subs, or subs on their own.  If you want satellites without subs you need to physically turn off or disconnect the subs. If you want subs alone, you need to select Channel 4 in the Output box. 

Hi Keith,
A brief aside from baby stuff - our new son Kobi (our second) was born yesterday. 6 lbs 19 inches, all are doing well. A future Audyssey user/audiophile has entered the world LOL...

HST, I did a baseline REW sweep over the weekend as part of getting my Trinnov thing going, and I actually ran a plot of my surrounds in my 5.2 system relative to one another, pre and post-Audyssey. Thanks to Audyssey Pro and the Target Curve Editor, Audyssey did a great job hammering down a 6 db+ hump at about 300 Hz, and providing a more gentle slope downward in my FR from about 8 kHz down than in the pre-Audyssey run. Normally we don't care about surrounds per se with our REW plots all that much, but it was reassuring to see that Audyssey does dial them in.
post #4545 of 9491
Quote:
Originally Posted by sdrucker View Post
 
Quote:
Originally Posted by kbarnes701 View Post

De nada,

No - you can choose any two with or without subs, or subs on their own.  If you want satellites without subs you need to physically turn off or disconnect the subs. If you want subs alone, you need to select Channel 4 in the Output box. 

Hi Keith,
A brief aside from baby stuff - our new son Kobi (our second) was born yesterday. 6 lbs 19 inches, all are doing well. A future Audyssey user/audiophile has entered the world LOL...

HST, I did a baseline REW sweep over the weekend as part of getting my Trinnov thing going, and I actually ran a plot of my surrounds in my 5.2 system relative to one another, pre and post-Audyssey. Thanks to Audyssey Pro and the Target Curve Editor, Audyssey did a great job hammering down a 6 db+ hump at about 300 Hz, and providing a more gentle slope downward in my FR from about 8 kHz down than in the pre-Audyssey run. Normally we don't care about surrounds per se with our REW plots all that much, but it was reassuring to see that Audyssey does dial them in.

 

Congratulations yet again, Stuart. Please give my best wishes to Mrs Stuart too!

 

Did you graph the surrounds after checking them out?  I've never even measured the surrounds at all.

post #4546 of 9491
Quote:
Originally Posted by AustinJerry View Post

Question for anyone who might have a theory:  in the attached measurements, why would Left+Right exhibit a steep roll-off in the high end, when Left and Right measured independently don't exhibit a similar roll-off?





You get high end cancellation when running both channels UNLESS the mic is EXACTLY the same distance from each source. What your seeing is typical when the mic ISN'T exactly the same distance. The wavelength at 15K is less than an inch, so if your mic is 1/4" off, well, you can see why this happens.


Its a bit of a moot point since your ears are not located where your nose is though wink.gif
Edited by jim19611961 - 9/10/13 at 10:10am
post #4547 of 9491
Quote:
Originally Posted by kbarnes701 View Post

Congratulations yet again, Stuart. Please give my best wishes to Mrs Stuart too!

Did you graph the surrounds after checking them out?  I've never even measured the surrounds at all.

Yup - I'm going to remeasure because (as a purist haha) I forgot to set the trims back to my Audyssey settings after I'd level matched them for Audyssey off (no RC), but after I redo the comparison I'll post it. I don't expect the results to change much, since the surrounds were essentially at a similar level vs. one another either way. I was actually pleasantly surprised that there was as much correction as I observed.
post #4548 of 9491

Nice to hear from you, Jim.  And thanks for a very plausible explanation.  I am pretty sure that I could never achieve a mic placement that ensures it is exactly centered, so I'll expect some variances in the top end attributable to mic placement going forward.  This is very nice to know.

 

"Its a bit of a moot point since your ears are not located where your nose is though".

 

I wouldn't be so sure, Jim.  People say I resemble my Mother, who is pictured here:

 


Edited by AustinJerry - 9/10/13 at 10:27am
post #4549 of 9491
Quote:
Originally Posted by shpitz View Post

KB to the rescue! Thanks!

Is it possible to output from all channels at once through HDMI?
Quote:
Originally Posted by kbarnes701 View Post

De nada,

No - you can choose any two with or without subs, or subs on their own.  If you want satellites without subs you need to physically turn off or disconnect the subs. If you want subs alone, you need to select Channel 4 in the Output box. 

Keith, I raised a similar measurement question a couple of pages ago, and I believe that Jerry indicated that HDMI 4 only captures the LFE .1 signal. My new understanding is that to measure subs alone you have to either disconnect L+R speakers or use AVR to temporarily disengage L+R speakers. Please correct if this interpretation is not accurate.
post #4550 of 9491
Quote:
Originally Posted by AustinJerry View Post

Nice to hear from you, Jim.  And thanks for a very plausible explanation.  I am pretty sure that I could never achieve a mic placement that ensures it is exactly centered, so I'll expect some variances in the top end attributable to mic placement going forward.  This is very nice to know.

"Its a bit of a moot point since your ears are not located where your nose is though".

I wouldn't be so sure, Jim.  People say I resemble my Mother, who is pictured here:



For those using a Dayton Omnimic, this isnt a problem since measurements are carried out in real time. You can just run both channels, look at the curve, and keep moving the mic slightly until the high end maxes out. This is also a neat process by which you can determine where the exact center spot is so you can confirm your listening chair is in the right spot.

In REW, you might be able to run a 10k or 15K sine wave out of both channels and look for when the recording level(s) is at its highest. i havent tried it, but this might work.

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

I miss talking to you guys also. But the direction of the thread has gotten away from room treatment and measurement analysis mostly, so I haven't had anything to contribute in a while. Still, I check in look at things smile.gif
Edited by jim19611961 - 9/10/13 at 11:18am
post #4551 of 9491
Quote:
Originally Posted by ggsantafe View Post



Keith, I raised a similar measurement question a couple of pages ago, and I believe that Jerry indicated that HDMI 4 only captures the LFE .1 signal. My new understanding is that to measure subs alone you have to either disconnect L+R speakers or use AVR to temporarily disengage L+R speakers. Please correct if this interpretation is not accurate.

 

 

Not Keith, but as long as you understand what you are doing, there shouldn't be an issue.  Connecting channels 1 and 2, invoking bass management, and turning off the left and right speakers will route the REW test sweep to the connected subs.  Connecting channel 4, which is the LFE channel IIUC, would route the REW signal to the subs as well.  In theory, both should yield similar results.  Remember, there is a HPF of 120Hz (or lower for some people) on the AVR's LFE channel.

 

You may recall that my laptop only supports HDMI with two channels, so sometimes I am negligent in recommending the use of channel 4.

post #4552 of 9491
Quote:
Originally Posted by jim19611961 View Post


For those using a Dayton Omnimic, this isnt a problem since measurements are carried out in real time. You can just run both channels, look at the curve, and keep moving the mic slightly until the high end maxes out. This is also a neat process by which you can determine where the exact center spot is so you can confirm your listening chair is in the right spot.

In REW, you might be able to run a 10k or 15K sine wave out of both channels and look for when the recording level(s) is at its highest. i havent tried it, but this might work.

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

I miss talking to you guys also. But the direction of the thread has gotten away from room treatment and measurement analysis mostly, so I haven't had anything to contribute in a while. Still, I check in look at things smile.gif

 

 

I determine exact center by running a 1-position Audyssey calibration and observing the measured distances.  IMHO, this is easier, and likely just as exact, Jim.

post #4553 of 9491
Quote:
Originally Posted by AustinJerry View Post


Not Keith, but as long as you understand what you are doing, there shouldn't be an issue.  Connecting channels 1 and 2, invoking bass management, and turning off the left and right speakers will route the REW test sweep to the connected subs.  Connecting channel 4, which is the LFE channel IIUC, would route the REW signal to the subs as well.  In theory, both should yield similar results.  Remember, there is a HPF of 120Hz (or lower for some people) on the AVR's LFE channel.

Minor nitpick, Jerry: most modern AVRs have an adjustable HPF up to 120 Hz for the LFE channel. Certainly Audyssey-equipped AVRs do, above and beyond any speaker-specific crossover settings.

But not all....ask a Pioneer user, for example. IIRC their LFE HPF is determined by the crossover setting for the mains, and the LFE rolls off at 12 db/octave after that point. In practical terms, that works out to about 120 Hz for an 80 Hz crossover point, with 118 to 124 Hz as the -6 db point - exact Hz depends on the AVR. But if one were to use a lower crossover, e.g. 50 Hz, you'd be down more like -12 db or worse at 120 Hz.

If anyone's curious: http://www.avsforum.com/t/1112470/official-pioneer-mcacc-thread/4110

I have a similar issue with the R-972 I'm testing. They use a measured F6 point for the subs on the high pass to help determine speaker crossover points, relative to the observed F6 low pass for satellites. Not sure I really that, since I'm still working out where that takes us given the dips you see in sub response > 100 Hz on REW. If I wind up with consistently crazy crossovers, such as 200 Hz for my powered Mythos STs (currently 80 Hz with XT32) after a Trinnov run, I might have to reconsider some positioning things. I've learned to like my 100 Hz crossover for my centers, and 120 Hz for my surrounds, but I draw the line with 100 Hz+ crossover for mains.
Edited by sdrucker - 9/10/13 at 12:26pm
post #4554 of 9491
Quote:
Originally Posted by ggsantafe View Post
 
Quote:
Originally Posted by shpitz View Post

KB to the rescue! Thanks!

Is it possible to output from all channels at once through HDMI?
Quote:
Originally Posted by kbarnes701 View Post

De nada,

No - you can choose any two with or without subs, or subs on their own.  If you want satellites without subs you need to physically turn off or disconnect the subs. If you want subs alone, you need to select Channel 4 in the Output box. 

Keith, I raised a similar measurement question a couple of pages ago, and I believe that Jerry indicated that HDMI 4 only captures the LFE .1 signal. My new understanding is that to measure subs alone you have to either disconnect L+R speakers or use AVR to temporarily disengage L+R speakers. Please correct if this interpretation is not accurate.

 

Jerry has already replied, but wrt to the bolded bit above, I am not even sure what that means. The 0.1 LFE channel only exists wrt to movie soundtracks. REW does not emulate movie soundtracks with its test tones AFAIK and AIUI - it just sends a full range sweep to the AVR which will then deal with it according to how the bass management in the AVR is set. And in my case, the bass management is to set to use a XO and to route information below that XO to the sub channel. I can't see what 0.1 has to do with it.  ICBW of course.... ;)

post #4555 of 9491
Quote:
Originally Posted by jim19611961 View Post

For those using a Dayton Omnimic, this isnt a problem since measurements are carried out in real time. You can just run both channels, look at the curve, and keep moving the mic slightly until the high end maxes out. This is also a neat process by which you can determine where the exact center spot is so you can confirm your listening chair is in the right spot.
 

 

The 'real time measuring' aspect of OmniMic is sometimes very useful and I miss it when using REW. It is much easier, for example, with OM to adjust the sub distances (delays) when trying to optimise the response around the splice. You can tweak the distances and observe the effect in real time on the graph - as opposed to taking a load of separate measurements and then comparing them. 

post #4556 of 9491
Quote:
Originally Posted by kbarnes701 View Post

The 'real time measuring' aspect of OmniMic is sometimes very useful and I miss it when using REW. It is much easier, for example, with OM to adjust the sub distances (delays) when trying to optimise the response around the splice. You can tweak the distances and observe the effect in real time on the graph - as opposed to taking a load of separate measurements and then comparing them. 

You just need fast reflexes, Keith....biggrin.gif....and a second person willing to sit and tweak distances while you measure...

So now you understand about the baby LOL...
post #4557 of 9491
Keith - I dug up some of the previous quotes I was thinking about when I posted my response - lets look at AVMike's comments and see if we can determine a measuring methodology difference between using HDMI 4 and/or turning off front speakers when tryiing to measure sub only response. I'm just looking for the most accurate & effective method to test sub only response
Quote:
Originally Posted by kbarnes701 View Post

Jerry has already replied, but wrt to the bolded bit above, I am not even sure what that means. The 0.1 LFE channel only exists wrt to movie soundtracks. REW does not emulate movie soundtracks with its test tones AFAIK and AIUI - it just sends a full range sweep to the AVR which will then deal with it according to how the bass management in the AVR is set. And in my case, the bass management is to set to use a XO and to route information below that XO to the sub channel. I can't see what 0.1 has to do with it.  ICBW of course.... wink.gif
Quote:
Originally Posted by AV_mike View Post

First off, REW has never allowed the same channel number in both Output selections. HDMI channel no. 4 is the LFE channel, and its output is boosted by 10dB within your AVR - that's why you're getting higher output. There really is no point using the timing reference unless you are performing timing measurements, absolute ETC for instance - or you want to drive two distinct channels at the same time, left & right together.
Regards, Mike.

Quote:
Originally Posted by ggsantafe View Post


Keith, I raised a similar measurement question a couple of pages ago, and I believe that Jerry indicated that HDMI 4 only captures the LFE .1 signal. My new understanding is that to measure subs alone you have to either disconnect L+R speakers or use AVR to temporarily disengage L+R speakers. Please correct if this interpretation is not accurate.
Quote:
Originally Posted by AV_mike View Post

post #4558 of 9491
Quote:
Originally Posted by sdrucker View Post
 
Quote:
Originally Posted by kbarnes701 View Post

The 'real time measuring' aspect of OmniMic is sometimes very useful and I miss it when using REW. It is much easier, for example, with OM to adjust the sub distances (delays) when trying to optimise the response around the splice. You can tweak the distances and observe the effect in real time on the graph - as opposed to taking a load of separate measurements and then comparing them. 

You just need fast reflexes, Keith....biggrin.gif....and a second person willing to sit and tweak distances while you measure...

So now you understand about the baby LOL...

 

LOL. Real time measuring is really cool though sometimes. It's the one thing I miss with REW.

post #4559 of 9491
Quote:
Originally Posted by kbarnes701 View Post

ROFL. I hadn’t considered that, Jerry, but I think you are right. You know, if I got rid of the side tables to the side of each seat, I could fit two more Submersives in.... hmmmm.... and if I went for HPs instead of F2s, then the HPs could serve as the tables themselves. Jerry, you might be on to something... smile.gif

Anyone think 4 SubMs in a room of about 1000 cu ft is too much?  Or is the consensus that you can never have too much woofage?  LOL.
On woofge:
My room is 900 ft3 and I thought until about March that 2 klipsch sub 10's yeah, O.K.
Then I got the REW and Umm mike and saw that,\. heh What?
So tried recommended movementsand placements but 33-35 and below was mostly missing
Several months later . . . Sub 10's OUT!
BF 24" THTLP - IN!
Initial testing/ listening ;
No such thing as too much woofage, especially with a WAF of ZERO
.
post #4560 of 9491
Quote:
Originally Posted by kbarnes701 View Post
 
Quote:
Originally Posted by sdrucker View Post
 
Quote:
Originally Posted by kbarnes701 View Post

The 'real time measuring' aspect of OmniMic is sometimes very useful and I miss it when using REW. It is much easier, for example, with OM to adjust the sub distances (delays) when trying to optimise the response around the splice. You can tweak the distances and observe the effect in real time on the graph - as opposed to taking a load of separate measurements and then comparing them.

You just need fast reflexes, Keith....biggrin.gif....and a second person willing to sit and tweak distances while you measure...

So now you understand about the baby LOL...

 

LOL. Real time measuring is really cool though sometimes. It's the one thing I miss with REW.

 

Since you still own both, have you had a chance to experiment using the UMM-6 with OM (and how it compares relative to the OM mic)?  I know you've been on a self-imposed measurement hiatus so this is more of a rhetorical question that could serve as a reminder of things to do when your ban is lifted (along with the Behringer requests)! :D  While it might pose an ethical dilemma for those not owning both, I'm curious if using the UMM-6 mic with OM software (or any other real-time analyzer for that matter) would be enough to see "relative" improvements in speaker placement to minimize the cycle Jerry describes above?  I agree that this is probably the only thing I miss with my OM kit vs. REW and USB mic.

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