Simplified REW Setup and Use (USB Mic & HDMI Connection) Including Measurement Techniques and How To Interpret Graphs - Page 385 - AVS Forum
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post #11521 of 12768 Old 09-06-2014, 02:49 AM
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Originally Posted by 3ll3d00d View Post
It is preferable to use the same scale throughout for dealing with XO, i.e. 15-300 & no smoothing.

is that last post really a combined response? the measurement name includes "no sub" in each case

what sub is it? it looks to be rolling off from 80-90Hz anyway

Can you dump the mdat somewhere? gdrive etc
Sorry...bad terminology on my part. When I said combined, I simply meant all of them were overlaid in one graph. My sub is a Rythmik D15SE. I don't think its naturally rolling off at 80. Take a look at the LFE graph.

mdat file: https://www.dropbox.com/s/61di79z7dd...ents.mdat?dl=0
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post #11522 of 12768 Old 09-06-2014, 02:58 AM
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Quote:
Originally Posted by Bluescale View Post
Sorry...bad terminology on my part. When I said combined, I simply meant all of them were overlaid in one graph. My sub is a Rythmik D15SE. I don't think its naturally rolling off at 80. Take a look at the LFE graph.

mdat file: https://www.dropbox.com/s/61di79z7dd...ents.mdat?dl=0
yes true, the XO=200 graph doesn't look like a 200Hz XO then to me. Are you sure it is set to 200Hz? Anyway no matter as the LFE one will suffice.

Have you got combined L+SW, R+SW, C+SW measurements with the different delays set to illustrate what you were saying about the combined response? I would be curious to see 1 mdat with all that in.

Are you using manual PEQ here until Dirac arrives? If so, I would clean up the modal resonances before going further to reduce the noise in the charts.
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post #11523 of 12768 Old 09-06-2014, 03:03 AM
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User error...I had the crossover set to 80, not 200 for that particular speaker. This is what it should look like:

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post #11524 of 12768 Old 09-06-2014, 03:13 AM
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Here's what it looks like with the PEQ filters for the sub in place:



And, since I haven't posted it yet, a waterfall with the PEQ in place:



I'll take a quick series of measurements with each speaker +sub, crossed over 80 and post the results.
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post #11525 of 12768 Old 09-06-2014, 03:37 AM
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Originally Posted by 3ll3d00d View Post
Have you got combined L+SW, R+SW, C+SW measurements with the different delays set to illustrate what you were saying about the combined response? I would be curious to see 1 mdat with all that in.
Wow...I wish I'd actually done this sweep earlier rather than trying to rely on the SPL meter to tell me what was going on. Horrible things are happening when the Right speaker and the sub come together. The others look adequate:

Left + Sub, XO = 80:


Right + Sub, XO = 80:


Center + Sub, XO = 80:


The right speaker had the best natural response at 80hz in the room, but it looks like crap once I add the sub. Where do I go from here?

mdat: https://www.dropbox.com/s/jryhewsj5h...ined.mdat?dl=0
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post #11526 of 12768 Old 09-06-2014, 03:54 AM
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Quote:
Originally Posted by Bluescale View Post
Where do I go from here?
Bed probably given your time zone

Ultimately you have a few choices

- adjust delays to get the best balance across the channels
- adjust the crossover
- if it is a minimum phase dip (probably unlikely), boost your way out of it (be wary of eating up headroom and just producing distortion

Does the mdat contain the separate responses and the combined ones? I am curious to see if we can get any decent predictions on paper even with no loopback.
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post #11527 of 12768 Old 09-06-2014, 03:59 AM
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Originally Posted by 3ll3d00d View Post
Bed probably given your time zone
Ye...the email notification that there was a response came in right as I was about to shut down and go to bed. I'm headed there in a minute.

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Originally Posted by 3ll3d00d View Post
Does the mdat contain the separate responses and the combined ones? I am curious to see if we can get any decent predictions on paper even with no loopback.
The mdat does indeed have individual measurements of the channels, the sub and the combined responses. It also has the sub pre and post EQ filters applied.

I'm going off of memory here, but I think both 60 and 100 showed possibility. I'll have to play with that tomorrow...

Last edited by Bluescale; 09-06-2014 at 04:00 AM. Reason: fixed quoting error
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post #11528 of 12768 Old 09-06-2014, 07:59 AM
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I think the advice you have been receiving from the d00d is all very good. Couple of minor comments. Whether you optimize the phase response at the crossover for the center or the mains depends on your listening habits. For example, I rarely listen to music in two-channel mode, I usually use PLII Music. Since bass is mono, this means the bass is routed to the center channel (and to the subs by virtue of bass management, of course). And for television or movie viewing, the signal is usually Dolby Digital, which again routes bass frequencies to the center channel. So, in my case, I optimize the phase using the center+sub signal. Of course, when I think I am done, I check the mains+sub, just to see if there is a significant difference. In my system the difference is usually minor, so I am not faced with the same trade-off you are. Regardless, IMO it is center+sub that is the best signal to use. Also, keep in mind that it would be quite rare that you would be listening to just the left or just the right channel. When optomixing frequency response below 300Hz, I think it is always better to measure L+R+sub(s), not just each channel separately. Measuring higher frequencies is entirely different, however. The interaction between the left and right can significantly impact frequency response in the higher frequencies if your mic is not dead center, so for full sweep measurements (to 20,000Hz), measure left and right separately. With REW, it's always picking the right measurement for what you are trying to analyze.

As to the distance differences between your LCR's, 5 inches is quite small. I am fairly OCD, so if it were me, I would adjust the positioning of your speakers so that the distances from the LCR to the MLP are all the same. I know you don't have auto EQ yet, but for example, I run a 1-position Audyssey calibration to calculate and adjust speaker positioning until Audyssey shows that the distances are exactly the same. I believe that symmetry is a good first step towards eliminating some of the phase and frequency response anomalies in a listening room.

Having said all that, I don't think your center+sub measurement looks bad at all. If you can't improve that small dip at 50Hz by moving the sub slightly, I would wait for auto EQ to see what happens. And as for the other two graphs, as I said, I would prefer to look at L+R+sub, if you get a chance to run that measurement.

Have you posted room pics and room dimensions yet? I have advocated on a number of occasions that troubleshooting would be easier if posters would create a "My Setup" thread with room layout and pictures, similar to the one in my sig.
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Last edited by AustinJerry; 09-06-2014 at 10:27 AM.
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post #11529 of 12768 Old 09-06-2014, 08:07 AM
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Quote:
Originally Posted by Bluescale View Post
The right speaker had the best natural response at 80hz in the room, but it looks like crap once I add the sub. Where do I go from here?
Remember the talk about the crossovers, the 12dB/octave natural roll off and cascading with 12dB/octave electrical roll off. The thing is that the left channel doesn't have such a 'roll off' behavior at the crossover region (as you tell it is the best natural response at 80... and bellow it) and so - phase is behaving differently at that frequency also.

The rule is - first equalize both sub and mains, targeting mains for a roll off at the crossover frequency and at least an octave below it (you can do it in REW EQ tab, the defaults are good for 80Hz crossover). And then measure combined response. As your speakers are capable of reproducing a lot less than 80 Hz you should 'emulate' the roll off with PEQ.

This would be much more convenient if the 24db/octave would be available for sub (you would then need to just EQ to flat one octave away of the crossover)... but it isn't as you know.
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post #11530 of 12768 Old 09-06-2014, 09:51 AM
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Originally Posted by Zzzzz... View Post

Please find attached my first graphs. Currently I'm just trying to optimize sub placement. The graph shows 2 frequency responses with the sub in its original position (close to a side wall, roughly mid-wall) and with the sub placed in a corner. I originally didn't place the sub in the corner as I expected it would give me worse results but it looks like it gives me a smoother response. What do people think of these responses? Any feedback most welcome (I'm completely new to room optimization).
Plugging in your room dimensions into the room mode calculator produces these results:



Because your room's dimensions are quite close to each other, almost like a cube, your primary modes are all in the 47-65Hz range. Placing a sub in a corner will excite the modes and, as expected, you have a peak in the 47-52Hz range. By moving the sub out of the corner, my bet is the peak will disappear. In other words, I think there are still some better places to locate the sub. Try some, and measure the results.
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post #11531 of 12768 Old 09-06-2014, 10:40 AM
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Back to HD's issue. Over in the Audyssey thread, one self-proclaimed expert says that the AVR's output level will drop if Audyssey is turned on. In order to test out his theory, I generated a -30dBFS Pink Noise test tone from my left speaker, opened the REW SPL Logger, and measured the output level of the test tone with Audyssey off, and then Audyssey on. Results:

Audyssey off:



Audyssey On:



As you can see, the pink noise level is essentially exactly the same, which contradicts the claim in the Audyssey thread. Of course, this is only one data point, and if anyone questions this conclusion, I encourage them to run the test themselves and post the results.

We are still looking forward to HD's test results, hopefully sometime this weekend.
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post #11532 of 12768 Old 09-06-2014, 11:21 AM
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Whether you optimize the phase response at the crossover for the center or the mains depends on your listening habits.
This room is exclusively my theater room, so the center is indeed the most critical channel for me. That's what I've been using, and it's good to have confirmation that my thought process in that was correct.

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As to the distance differences between your LCR's, 5 inches is quite small. I am fairly OCD, so if it were me, I would adjust the positioning of your speakers so that the distances from the LCR to the MLP are all the same. I know you don't have auto EQ yet, but for example, I run a 1-position Audyssey calibration to calculate and adjust speaker positioning until Audyssey shows that the distances are exactly the same. I believe that symmetry is a good first step towards eliminating some of the phase and frequency response anomalies in a listening room.
Good points. At one point, I had actually gone through and and use a tape measure to verify that every corner of the speaker was the same distance from the back walls, side walls and tv. Since then, I've change things around a bit, and haven't gotten quite so precise. I'll give it a shot and see what comes of a bit more precision.

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Having said all that, I don't think your center+sub measurement looks bad at all. If you can't improve that small dip at 50Hz by moving the sub slightly, I would wait for auto EQ to see what happens. And as for the other two graphs, as I said, I would prefer to look at L+R+sub, if you get a chance to run that measurement.
I've tried moving the sub all over. It's been in the corner. It's been mid wall. It's been 2/3 of the way down the wall. I've had it right against the wall and then away from the wall. The current location gives me the best overall response. That said, when I get the chance, I will do the sub crawl with REW instead of my ears to see if I missed anything.

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Have you posted room pics and room dimensions yet? I have advocated on a number of occasions that troubleshooting would be easier if posters would create a "My Setup" thread with room layout and pictures, similar to the one in my sig.
I don't think I could do the room justice in photos. It is certainly one of the weirdest rooms I've ever seen. It's a converted garage, but it's not typical in any sense. The easiest dimensions are that it's 19'x12', but even that doesn't quite get it. About 15 feet back, on the left hand side, there wall juts back into the room 16". It then extends back another 4' with these narrower dimensions.

Room height is interesting, to say the least. The ceiling is sloped, but not in a typical, end to end fashion. In the front end, by the television and front speakers, the ceiling is ~6'8". It then keeps sloping up to 11'6", and hits that peak at about 14 feet into the room. Then, instead of leveling off, there's a ledge that drops down ~3'9". This ledge is about 6" thick, and the back side of the ledge goes back up 11", giving the back 4'6" of the room a flat ceiling height of 8'8".

Oh, and the left wall has a 6'x4' picture window, which necessitate my surround speakers being mounted too high (about 8' off the ground to the bottom of the speaker), if I remember correctly. And the floor is concrete.

Yeah, it's a mess...
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post #11533 of 12768 Old 09-06-2014, 11:31 AM
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The room shape certainly doesn't allow for conventional room mode analysis, for sure. But that doesn't mean you can't achieve excellent results, it just takes some work. You may indeed have the sub in its best location, so maybe waiting on the arrival of the automated EQ upgrade is the logical next step.
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post #11534 of 12768 Old 09-06-2014, 03:55 PM
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Quote:
Originally Posted by AustinJerry View Post
Back to HD's issue. Over in the Audyssey thread, one self-proclaimed expert says that the AVR's output level will drop if Audyssey is turned on. In order to test out his theory, I generated a -30dBFS Pink Noise test tone from my left speaker, opened the REW SPL Logger, and measured the output level of the test tone with Audyssey off, and then Audyssey on. Results:

As you can see, the pink noise level is essentially exactly the same, which contradicts the claim in the Audyssey thread. Of course, this is only one data point, and if anyone questions this conclusion, I encourage them to run the test themselves and post the results.

We are still looking forward to HD's test results, hopefully sometime this weekend.
Aww hellz. Here we go:

Audyssey 4th run (post AVR processor reset)
adjusted Mackies to 0dB gain and Audyssey came up with trims of:
L -7.5
C -6.5
R -9.0
Sub -1.5

After Audyssey, AUD ON AVR test tones register in REW SPL as:
L 69.9
C 69.5
R 69.2
Sub 71-72


After Audyssey, AUD OFF AVR test tones register in REW SPL as:
L 69.9
C 69.5
R 69.2
Sub 71-72

I erroneously remembered them being around 64dB a few runs back, but checking my notes they were identical. So the microprocessor reset has not changed the results of Audyssey. Interestingly enough, the SPL levels I got on this run were identical to the ones generated previously when I had the Mackies at -10dB gain and Audyssey set the trims in the positive.

HOWEVER

Audyssey is clearly limiting my volume output. I knew it seemed like I couldn't make any gains between AVR MV 0 and +15. Here is a log of me running a Pink PN -30dB via REW starting at AVR MV 0.



I placed the cursor where I hit +4 on the AVR. (I guess you'll have to trust me as it doesn't appear I included the cursor!) At this point I no longer heard an increase, and for the remainder you can see there was none, all the way to +15.

Alternatively disabling Audyssey, though having no effect on the AVR's pink noise (as shown earlier) did allow me to run the AVR louder.



I stopped at +8 as I was going to wake our baby and have to face the consequences.

Is there a way to defeat this Audyssey limit? Or should it even be there in the first place?!

OK, so that's issue #1 . On to the actual results. I was able to run a full -12dB FS sweep and still have 4dB of headroom this afternoon at AVR MV 0. Not sure what changed. Anyhow:

Audyssey run but off (so no sub BGC) but with my custom x-over of 120Hz and custom sub distance of 7.5ft



Audyssey ON with BGC but with my custom x-over of 120Hz and custom sub distance of 7.5ft


Audyssey ON with BGC with auto x-over of 70Hz and auto sub distance of 8.5ft


Now I realize that getting a flatter response isn't everything, so here are comparative waterfalls:

My custom x-over and distance


Auto


My uninformed opinion is that the custom settings are still superior--would love to get feedback on this.

And I don't really know how to properly read them, but the spectrograms have me believing perhaps I should stick with what Audyssey chose, as my custom settings seem to be making things worse over there...

custom


auto


The saga continues. Thank you for your continued attention.
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post #11535 of 12768 Old 09-06-2014, 04:13 PM
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As you can see, the pink noise level is essentially exactly the same, which contradicts the claim in the Audyssey thread.
What if you raise the SPL? Do you hit a limit at some point with one method versus the other? I didn't seem to be limited until I hit about 87dB...
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post #11536 of 12768 Old 09-06-2014, 04:13 PM
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I think the blue graph, Audyssey with 120Hz crossover, looks the best, and is pretty good. The fact that the measurement levels are around 90dB seems to indicate that the AVR is capable of a reasonable output level. And if I understand correctly, there is no mysterious 10dB drop in output level when Audyssey is engaged, correct?

As far as why Audyssey is limiting the max MV setting, I don't know what is happening there. I'll try to run some tests to duplicate what you are seeing.

So, now that you have completed the most recent Audyssey run, is the AVR functioning well enough that you can use it? How does it sound?
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post #11537 of 12768 Old 09-06-2014, 04:18 PM
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What if you raise the SPL? Do you hit a limit at some point with one method versus the other? I didn't seem to be limited until I hit about 87dB...
Not sure what you are asking. My test was with MV=0, which at -30dBFS measures 75dB at the MLP. If I were to achieve 87dB, that would be at a MV of +12. The limit on my AVR is +18. I did not try this test, because I don't know what this would prove.

I do know that for normal content, e.g. music or movies, Reference Level (MV=0) produces a painfully loud output at the MLP.
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post #11538 of 12768 Old 09-06-2014, 04:23 PM
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Originally Posted by AustinJerry View Post
I think the blue graph, Audyssey with 120Hz crossover, looks the best, and is pretty good. The fact that the measurement levels are around 90dB seems to indicate that the AVR is capable of a reasonable output level. And if I understand correctly, there is no mysterious 10dB drop in output level when Audyssey is engaged, correct?

As far as why Audyssey is limiting the max MV setting, I don't know what is happening there. I'll try to run some tests to duplicate what you are seeing.

So, now that you have completed the most recent Audyssey run, is the AVR functioning well enough that you can use it? How does it sound?
It's come a long way from having the sub at the front of the room! I'm exciting to integrate my second (garbage) sub as experimental fill (it tracks my good sub through most of the problem frequencies nicely!), and finish it all off with some PEQ with my miniDSP. Walk before you run and all that though!

It sounds much better. Honestly for a room with nothing but two bass traps and no furniture it isn't as echoy as I'd feared. Music is listenable now, and there aren't "holes" in the bass. The bass has tightened up too. Not so muddy.

It's a shame I have to lose my plexiglass rack door though. Cost a mint and causes utter havok in the charts (not shown above).

My room is usable, and a lot of my apprehension around this process has lifted knowing this room can sound good.

I'm getting pretty sick of running Audyssey though. Think I'm going to USE my room for a few hours before running any more tests.

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post #11539 of 12768 Old 09-06-2014, 04:31 PM
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Not sure what you are asking. My test was with MV=0, which at -30dBFS measures 75dB at the MLP. If I were to achieve 87dB, that would be at a MV of +12. The limit on my AVR is +18. I did not try this test, because I don't know what this would prove.

I do know that for normal content, e.g. music or movies, Reference Level (MV=0) produces a painfully loud output at the MLP.
Ignore any reference I made to specific SPL as I now realize I have no idea how to properly read those logs...

We're not looking for what is usable or practical (I can't handle any more than -10 on my AVR, so...95*dB?), we're trying to see if there is a volume limit imposed by Audyssey.

If your AVR goes to +18, throw on some ear protection, crank up the volume feeding it -30dB FS and see if you get steady volume increases all the way to +18 with Audyssey engaged. I suspect you won't--as that's what I discovered for my AVR.

Would I ever use it like this? No. Am I perfectly happy within the apparent constraints of Audyssey-allowable volumes? Absolutely. Do I want to know if what we're describing even exists?

Yes.

Inquiring minds want to know.

*ha ha--caught my math error!

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post #11540 of 12768 Old 09-06-2014, 05:08 PM
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Originally Posted by HDgaming42 View Post
If your AVR goes to +18, throw on some ear protection, crank up the volume feeding it -30dB FS and see if you get steady volume increases all the way to +18 with Audyssey engaged. I suspect you won't--as that's what I discovered for my AVR.

Would I ever use it like this? No. Am I perfectly happy within the apparent constraints of Audyssey-allowable volumes? Absolutely. Do I want to know if what we're describing even exists?

Yes.

Inquiring minds want to know.

*ha ha--caught my math error!
it makes no sense to send a low (-30dBFS) signal to a device and then boost the crap out of it by running the MV at +10 or whatever, it would not be surprising if you were clipping somewhere in the AVR in this situation. If you want to test this then ramp the sweep level instead while leaving the AVR MV at the same level, i.e. you want to test if your AVR is limiting your output then leave your AVR in a static state and vary the input level.

Having said that, at the end of the day Audyssey is an algorithm that runs on some DSP in your AVR, i.e. it's in the digital domain. If you feed that DSP a 0dBFS signal and that DSP is programmed to boost (anywhere through the frequency range) then how can it boost without clipping? The answer is it can't, it has to cut drop the level by the max boost amount instead. So yes, at the end of the day using DSP to boost loses digital headroom.

You might find it informative to take some readings from your preouts to see what is going on rather than just treating audyssey as a black box.
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post #11541 of 12768 Old 09-06-2014, 05:37 PM
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So yes, at the end of the day using DSP to boost loses digital headroom.
Agreed, but my point to HD is that even though some headroom may have been lost, the maximum output level (on my system at least) is still higher than I would ever use.

At this point, the test seems to be academic.

@HD, I'll think about how I might devise a test, using d00d's suggestions, but like you, I prefer to sit back a relax for a few days.

I'm pleased that we seem to be over the hump, and that you now have a system that you can enjoy.
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post #11542 of 12768 Old 09-06-2014, 05:51 PM
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Agreed, but my point to HD is that even though some headroom may have been lost, the maximum output level (on my system at least) is still higher than I would ever use.

At this point, the test seems to be academic.
yes absolutely, it's basically irrelevant unless you've lost too much gain (which can happen in some circumstances but not generally an issue with audyssey)
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post #11543 of 12768 Old 09-06-2014, 06:28 PM
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Plugging in your room dimensions into the room mode calculator produces these results:



Because your room's dimensions are quite close to each other, almost like a cube, your primary modes are all in the 47-65Hz range. Placing a sub in a corner will excite the modes and, as expected, you have a peak in the 47-52Hz range. By moving the sub out of the corner, my bet is the peak will disappear. In other words, I think there are still some better places to locate the sub. Try some, and measure the results.
I see. Thanks for that. I need to take a bit of a break though will probably be able to continue experimenting next weekend.



One last question for now: in REW, is it possible to disable graph zooming via the mouse wheel? (My mouse does not have a scroll wheel but rather it has a touch surface and accidentally brushing it is causing me to continuously be zooming my graphs by accident)
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post #11544 of 12768 Old 09-06-2014, 07:08 PM
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One last question for now: in REW, is it possible to disable graph zooming via the mouse wheel? (My mouse does not have a scroll wheel but rather it has a touch surface and accidentally brushing it is causing me to continuously be zooming my graphs by accident)
I don't know. But I do know you can disable the vertical scrolling behavior on your laptop's touchpad. That feature drives me crazy, and I always disable it.
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post #11545 of 12768 Old 09-06-2014, 08:53 PM
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Rew

Hello Jerry and all.
I am a complete noob when it comes to this REW and measuring. I have REW downloaded and purchased a UMIK and miniDSP. Jerry I've just downloaded your REW setup guide from post 275. Can I do your guide in steps, in other words can I do one thing today and another the next day as like I said I have a real hard time even using the new laptop I bought with Windows 8.1 I hope I'm not hi-jacking this thread as my intentions are to at least get a grasp on the setup procedures involved with REW. I've read through the entire setup, so now I plan on trying to start to get started. I realize there is a lot to do before even utilizing the REW software, so I hope that I can do this in stages and go back and do more another time or day, is this feasible? Thank you so much for your time and again, sorry for the extremely newbie questions. Since downloading your REW setup guide I thought I would come to the source of it all, and I believe that is here. Thank you again.
Respectively Jeffrey

j_nordi
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post #11546 of 12768 Old 09-06-2014, 09:14 PM
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Hello, Jeffrey, nice to see you here. There is no reason why you can't take things a slow as you would like. I think once you get started that things will pick up speed. Looking forward to your first measurements!
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post #11547 of 12768 Old 09-07-2014, 10:01 AM
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Aww hellz. Here we go:

Audyssey is clearly limiting my volume output. I knew it seemed like I couldn't make any gains between AVR MV 0 and +15. Here is a log of me running a Pink PN -30dB via REW starting at AVR MV 0.

Is there a way to defeat this Audyssey limit? Or should it even be there in the first place?!

The saga continues. Thank you for your continued attention.
I do not believe that the issue you are describing is "Audyssey" doing anything. It is well documented with the Denon AVP receiver, which I own, that engaging Audyssey can limit the maximum gain provided using the volume control and hence SPL. This is deliberately done by the receivers designers to prevent internal clipping from high gain corrections created by Audyssey. Disengaging Audyssey will therefore return the receiver back to its original gain structure and allow the volume control to exercise its full range.
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post #11548 of 12768 Old 09-07-2014, 10:33 AM
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I do not believe that the issue you are describing is "Audyssey" doing anything. It is well documented with the Denon AVP receiver, which I own, that engaging Audyssey can limit the maximum gain provided using the volume control and hence SPL. This is deliberately done by the receivers designers to prevent internal clipping from high gain corrections created by Audyssey. Disengaging Audyssey will therefore return the receiver back to its original gain structure and allow the volume control to exercise its full range.
The initial report by HDGamin ("Official" Audyssey thread (FAQ in post #51779)) reported that the sound level went down when he engaged Audyssey. This is an entirely different issue that having Audyssey limit the maximum gain, which is a recognized behavior well-documented by several recent quotes by RickardL in the Audyssey thread.

HST, I don't think we have been able to reproduce HDGaming's claim that the overall level goes down. I ran a test (documented earlier in this thread) that showed this was not true on my system. And HDGaming's most recent measurements seem to show similar output levels with Audyssey on or off. So, why he originally reported a big level difference remains a mystery.
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post #11549 of 12768 Old 09-07-2014, 12:21 PM
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The initial report by HDGamin ("Official" Audyssey thread (FAQ in post #51779)) reported that the sound level went down when he engaged Audyssey. This is an entirely different issue that having Audyssey limit the maximum gain, which is a recognized behavior well-documented by several recent quotes by RickardL in the Audyssey thread.

HST, I don't think we have been able to reproduce HDGaming's claim that the overall level goes down. I ran a test (documented earlier in this thread) that showed this was not true on my system. And HDGaming's most recent measurements seem to show similar output levels with Audyssey on or off. So, why he originally reported a big level difference remains a mystery.
Sorry, I missed the original posts. There is certainly no level shift in the AVP when engaging Audyssey unless the volume control is set well over 0dB when it is engaged.
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post #11550 of 12768 Old 09-07-2014, 12:26 PM
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I do not believe that the issue you are describing is "Audyssey" doing anything. It is well documented with the Denon AVP receiver, which I own, that engaging Audyssey can limit the maximum gain provided using the volume control and hence SPL. This is deliberately done by the receivers designers to prevent internal clipping from high gain corrections created by Audyssey. Disengaging Audyssey will therefore return the receiver back to its original gain structure and allow the volume control to exercise its full range.
Yes, thank-you. This has been explained by a few people now and makes complete sense to me. What I was seeing before did not make any sense.

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And HDGaming's most recent measurements seem to show similar output levels with Audyssey on or off. So, why he originally reported a big level difference remains a mystery.
The only difference between then and now was that I performed a microprocessor reset between tests...
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