Simplified REW Setup and Use (USB Mic & HDMI Connection) Including Measurement Techniques and How To Interpret Graphs - Page 373 - AVS Forum
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post #11161 of 11690 Old 08-26-2014, 06:33 AM
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Originally Posted by Bluescale View Post
It seems odd to me that you're disabling bass management to set your levels. Why not set it where you'd use it, and then turn off the sub or the mains, depending on where you're setting the level. Also make sure you're sending the correct narrow band pink noise for the type of speaker.
Force of habit I guess? This is the procedure I was following when trying to determine best placement of my sub. Just carried it over when setting levels it seems.
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post #11162 of 11690 Old 08-26-2014, 06:47 AM
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Force of habit I guess? This is the procedure I was following when trying to determine best placement of my sub. Just carried it over when setting levels it seems.
Did you get the chance to try the procedure I outlined?

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post #11163 of 11690 Old 08-26-2014, 07:10 AM
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I decided to revisit my bass management and EQ settings. First of all, I changed everything over to 80hz xover, and set the slope to 24dB/octave. Then I decided to see if I could successfully implement the Harman curve Markus recommended as a starting point. I found that implementing a specific curve was a lot more difficult than just attenuating peaks on the graph. I had to spend more time thinking about what I actually wanted to accomplish. Anyway, here are the results of my experimentation:

Sub:



Font Left:


Front Right:


Center:


All front speakers sub:


My waterfall reverb time has taken a bit of a step backward, and I'm not sure why. I did adjust the volume of the sub a tad bit, to make the curve Markus provided possible. Maybe that's why . Frequency response, on the other hand looks better to me. I'm not quite sure what to make of this. I'll give it a listen later today to see if it actually sounds better.

I had more sweeps, including other seating locations, but unfortunately REW crashed on me, and I hadn't been saving my work as diligently as I should have.

On another note, I did't get around to canceling my order of mineral wool, and it just shipped out yesterday. I could return it, but for the cost of shipping, I might as well keep it. With that in mind, I think I'll still build a few acoustic panels and see if they contribute anything positively to my room.

Here's the .mdat, in anyone cares:
https://www.dropbox.com/s/8m7zn86jwe...4%29.mdat?dl=0
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post #11164 of 11690 Old 08-26-2014, 07:41 AM
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Looks like you have two house curves applied, one in preferences and one in the EQ tool. You would need to set the marked values to zero first:

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post #11165 of 11690 Old 08-26-2014, 08:09 AM
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Originally Posted by AustinJerry View Post
Did you get the chance to try the procedure I outlined?
I did--yes. Was just preparing the images.

So it appears my AVR's test signals result in the sub being 10dB HOT. I suspect I have become accustomed to this exaggerated bass over the seven years I have used this amp, and miss it when it is lower.

I calibrated via the AVR to 75dB. Things sounded "correct" to me--or at least how I'm used to hearing them. Then I used REW to play back pink noise and raised the volume on the AVR to read 75dB each individually from L, C, R. When playing my sub with the sub-limited pink noise it registered--you guessed it--86dB.

I ran sweeps with both the AVR calibration and the REW calibration. With my limited understanding, it looks to me like REW has them far better level matched than my AVR, though they're a tad rocky ATM.






After I lowered the sub to match REW's pink noise I had to increase the volume so I was still reading a spectrogram peak near 90. Perhaps I should have left it as is so that the sub's level appears to "drop" as opposed to the higher frequencies increasing in volume...

edit - here's a 1/6 smoothed comparison which oddly shows a difference closer to an average of 5dB of difference between my AVR's idea of 75dB and REW's.


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post #11166 of 11690 Old 08-26-2014, 08:43 AM
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Originally Posted by HDgaming42 View Post
When playing my sub with the sub-limited pink noise it registered--you guessed it--86dB.
And you were NOT using the CH4 output in REW, correct?

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post #11167 of 11690 Old 08-26-2014, 09:08 AM
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And you were NOT using the CH4 output in REW, correct?
Correct. Channel 1 and 2 with the monitors switched off, bass management engaged at 80Hz.
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post #11168 of 11690 Old 08-26-2014, 10:49 AM
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Originally Posted by HDgaming42 View Post
I did--yes. Was just preparing the images.

So it appears my AVR's test signals result in the sub being 10dB HOT. I suspect I have become accustomed to this exaggerated bass over the seven years I have used this amp, and miss it when it is lower.

I calibrated via the AVR to 75dB. Things sounded "correct" to me--or at least how I'm used to hearing them. Then I used REW to play back pink noise and raised the volume on the AVR to read 75dB each individually from L, C, R. When playing my sub with the sub-limited pink noise it registered--you guessed it--86dB.
TBH, I don't think any of us know what you are doing any more. If you followed the procedure I posted yesterday, then by definition, you speaker levels are matched.

When you say you played "sub-limited pink noise" when measuring the sub, are you saying that this test tone is a different one that you used to adjust the MV until LCR were measuring 75dB? Then that means the "sub-limited pink noise" level is 10dB different than the other tone. Otherwise, there is no way that the sub could measure different than the main speakers. What you may be doing is using the "Speaker Cal" signal (see attached screen shot below) for the main speakers, and then the "Sub Cal" signal for the sub. I tested this out just now, and the "Sub Cal" signal output to the subs registers approximately 10dB lower than the "Speaker Cal" signal sent to the main speakers. This does not indicate a difference in the levels between mains and subs--it's just a difference in the REW signal. Is this what you are measuring?


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post #11169 of 11690 Old 08-26-2014, 11:15 AM
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The easiest way of matching a sub to the satellites is to play full bandwidth pink noise and adjust the 30 or 60Hz band until it reads the same as the 1kHz band in an 1/1 octave RTA.

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post #11170 of 11690 Old 08-26-2014, 11:33 AM
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Originally Posted by AustinJerry View Post
TBH, I don't think any of us know what you are doing any more. If you followed the procedure I posted yesterday, then by definition, you speaker levels are matched.

When you say you played "sub-limited pink noise" when measuring the sub, are you saying that this test tone is a different one that you used to adjust the MV until LCR were measuring 75dB? Then that means the "sub-limited pink noise" level is 10dB different than the other tone. Otherwise, there is no way that the sub could measure different than the main speakers. What you may be doing is using the "Speaker Cal" signal (see attached screen shot below) for the main speakers, and then the "Sub Cal" signal for the sub. I tested this out just now, and the "Sub Cal" signal output to the subs registers approximately 10dB lower than the "Speaker Cal" signal sent to the main speakers. This does not indicate a difference in the levels between mains and subs--it's just a difference in the REW signal. Is this what you are measuring?

I feel you. I really do. I will try to best document what I did, my results--and why I'm so confused.

Yes, I followed your procedure. Used REW just as the SPL meter--used my AVRs test tones and set each speaker to 75dB (though truthfully I used the gain pots on each monitor / sub and left the AVR at trim 0).

Then I did a full spectrum sweep in REW--the line marked "blue". Levels didn't look very "even" to me.

I then increased MV on the AVR so that the "Speaker Cal" out of L, C, and R independently measured 75dB each. Then I used "Sub Cal" and found the sub measuring 10dB higher at 86dB (which you're apparently saying is the expected response?) I'm guessing I should be using "full range" or "speaker cal" to set the sub level? I am finding this less than intuitive...

What confuses me is the result that followed.

I lowered the sub to be 75dB according to REWs "sub cal" pink noise via the volume knob on the sub. The overall level dropped (previously I was told to try to hit 90 when viewed in the spectrogram) so I boosted MV on the AVR until the spectrogram showed a peak of 90 doing a L + sub sweep.

At this point I ran a full sweep. The sweep looks more volume matched with the REW method (which I believe I'm being told is incorrect) versus the AVR method, which to me looks like the subwoofer's volume is set higher than the mains.

Does that clear anything up? Reveal where I've gone so horribly wrong? Is it as simple as only using "full range" in REW to calibrate the sub and then both my AVR and REW will agree?

Theory aside--which method looks more volume matched to you--AVR or REW?

Edit: re-reading this I am beginning to believe that the "sub cal" is meant solely for direct Channel 4 LFE usage where it would receive a 10dB boost in the receiver no? That first I would use speaker cal or full range to set the sub via Channels 1 and 2 (for bass management), and then optionally use Sub Cal to set SPL for LFE via Channel 4?

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post #11171 of 11690 Old 08-26-2014, 11:42 AM
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Originally Posted by markus767 View Post
^
The easiest way of matching a sub to the satellites is to play full bandwidth pink noise and adjust the 30 or 60Hz band until it reads the same as the 1kHz band in an 1/1 octave RTA.

I'm very interested in alternative methods, but must admit I'm a bit lost by your picture. Perhaps it will become clear when I attempt to use the RTA.

The 1kHz matches neither the 30Hz or 60Hz SPL readings. Both of those frequencies are below my crossover.

I am lost and will have to google how to read a RTA as I am obviously not "getting it". I appreciate the effort.
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post #11172 of 11690 Old 08-26-2014, 11:59 AM
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Originally Posted by markus767 View Post
^
The easiest way of matching a sub to the satellites is to play full bandwidth pink noise and adjust the 30 or 60Hz band until it reads the same as the 1kHz band in an 1/1 octave RTA.
Interesting, and logical. Here is what I measured, without any adjustments to existing levels:



Would you agree that this is "close enough"? Thanks for proposing this method, by the way. We always appreciate your suggestions.

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post #11173 of 11690 Old 08-26-2014, 12:01 PM
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Originally Posted by HDgaming42 View Post
I'm very interested in alternative methods, but must admit I'm a bit lost by your picture. Perhaps it will become clear when I attempt to use the RTA.

The 1kHz matches neither the 30Hz or 60Hz SPL readings. Both of those frequencies are below my crossover.

I am lost and will have to google how to read a RTA as I am obviously not "getting it". I appreciate the effort.
Set the RTA as shown in the picture. Send pink noise from REW through channel 1. It will play back from the left speaker and the sub. Adjust the sub level so it matches the 1kHz band in the RTA.

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post #11174 of 11690 Old 08-26-2014, 12:01 PM
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Originally Posted by markus767 View Post
^
Looks like you have two house curves applied, one in preferences and one in the EQ tool.
Haha! Don't I feel stupid. I felt like the slope on the high end seemed way too severe...

<sigh>

Back to the theater room...
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post #11175 of 11690 Old 08-26-2014, 12:03 PM
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Originally Posted by HDgaming42 View Post
I feel you. I really do. I will try to best document what I did, my results--and why I'm so confused.

Yes, I followed your procedure. Used REW just as the SPL meter--used my AVRs test tones and set each speaker to 75dB (though truthfully I used the gain pots on each monitor / sub and left the AVR at trim 0).

Then I did a full spectrum sweep in REW--the line marked "blue". Levels didn't look very "even" to me.

I then increased MV on the AVR so that the "Speaker Cal" out of L, C, and R independently measured 75dB each. Then I used "Sub Cal" and found the sub measuring 10dB higher at 86dB (which you're apparently saying is the expected response?) I'm guessing I should be using "full range" or "speaker cal" to set the sub level? I am finding this less than intuitive...

What confuses me is the result that followed.

I lowered the sub to be 75dB according to REWs "sub cal" pink noise via the volume knob on the sub. The overall level dropped (previously I was told to try to hit 90 when viewed in the spectrogram) so I boosted MV on the AVR until the spectrogram showed a peak of 90 doing a L + sub sweep.

At this point I ran a full sweep. The sweep looks more volume matched with the REW method (which I believe I'm being told is incorrect) versus the AVR method, which to me looks like the subwoofer's volume is set higher than the mains.

Does that clear anything up? Reveal where I've gone so horribly wrong? Is it as simple as only using "full range" in REW to calibrate the sub and then both my AVR and REW will agree?

Theory aside--which method looks more volume matched to you--AVR or REW?

Edit: re-reading this I am beginning to believe that the "sub cal" is meant solely for direct Channel 4 LFE usage where it would receive a 10dB boost in the receiver no? That first I would use speaker cal or full range to set the sub via Channels 1 and 2 (for bass management), and then optionally use Sub Cal to set SPL for LFE via Channel 4?
Regarding the blue line--did you expect a perfectly flay line just because you set the speaker levels? It doesn't work that way.

Where did you go wrong? IMO, you set the levels properly using the AVR test tones. You should have considered this to be good enough. Instead, you went into REW and started outputting different tones and taking measurements that you don't seem to understand very well, and then you became confused. Why didn't you just leave well enough alone?

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post #11176 of 11690 Old 08-26-2014, 12:05 PM
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Originally Posted by Bluescale View Post
Haha! Don't I feel stupid. I felt like the slope on the high end seemed way too severe...

<sigh>

Back to the theater room...
Never feel stupid. This is a "learning moment", and why we are here. I am encouraged by your progress, and the fact that you seem to like to experiment. Of course, we are all anxiously awaiting your Dirac implementation, and subsequent measurements. Have you received any news WRT when the upgrade to the XMC-1 might happen?

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post #11177 of 11690 Old 08-26-2014, 01:16 PM
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Set the RTA as shown in the picture. Send pink noise from REW through channel 1. It will play back from the left speaker and the sub. Adjust the sub level so it matches the 1kHz band in the RTA.
Thanks--I will give this a try.

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Regarding the blue line--did you expect a perfectly flay line just because you set the speaker levels? It doesn't work that way.
Of course not. I thought I'd laid out quite explicitly as to why I'm confused. I guess not.

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Where did you go wrong? IMO, you set the levels properly using the AVR test tones. You should have considered this to be good enough. Instead, you went into REW and started outputting different tones and taking measurements that you don't seem to understand very well, and then you became confused. Why didn't you just leave well enough alone?
This came about because I'm learning to use REW in the "Simplified REW Setup and Use" thread.

With REW being as versatile as it is, I don't think it's unreasonable to want to learn to use it properly for speaker level matching. My mistake(s) were plentiful--but I believe this is the place to make them, is it not? Initially I was using Sub Cal to set the LFE via Channel 4. This would have been correct for LFE, but not necessarily bass management.

Then I learned I had to output to channels 1 and 2 to set the (non-LFE) subwoofer levels. What I missed (apparently) is that you cannot use "sub cal" pink noise for this purpose.

I am curious what setting levels with the RTA will show. Comparing smoothed responses between the apparently correct AVR and the 10dB too low REW (because of using "Sub Cal") I'd have to say the response on either side of the crossover actually appears to be closer the incorrect REW way.

No one has commented on that yet. This is what I find confusing.

I find REW fascinating, and there is so much to learn in regards to acoustics, traps, treatments, placement, level setting etc. in this hobby. We all have to start somewhere. I'm a DIY kind of guy and a tinkerer. "Set it and forget it" isn't really me. Thanks for the help thus far.

edit: I guess from a newcomers perspective it would be great for REW to have a "sub cal" level that is the same as the mains, and only drop it 10dB when fed to channel 4 as the LFE channel is the only one that needs this drop. As you learn more you realize you can just use "full range" and let your bass management handle it.

Selecting "Sub cal" had me believing that the pink noise was being generated only within subwoofer achievable frequencies, but at the same level as the mains. Hey, I'm learning.
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post #11178 of 11690 Old 08-26-2014, 01:46 PM
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Would you agree that this is "close enough"?
Yes, that's close enough.

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post #11179 of 11690 Old 08-26-2014, 01:55 PM
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Any one tried this: nanoAVR 8x8 ?

http://www.minidsp.com/products/mini...ox/nanoavr-8x8

http://www.stereophile.com/content/music-round-67

My humble Cinema
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post #11180 of 11690 Old 08-26-2014, 02:04 PM
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That seem like the correct procedure to me. Does your AVR not have internal test tones??
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It does, and if I use it directly after setting levels with REW my sub needs a 10db boost to reach 75dB. This boost also seems required if judging by my ears...
Hey HD, why don't you save yourself the headache and just set the levels with your AVRs internal test tones and an SPL meter (or REWs SPL meter)?? This is what I would do...and what I do.

Does your AVR have Audyssey? Any sort of auto-setup?? If so, why aren't you just using that? Do you not trust it??

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post #11181 of 11690 Old 08-26-2014, 02:15 PM
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Originally Posted by HDgaming42 View Post
edit: I guess from a newcomers perspective it would be great for REW to have a "sub cal" level that is the same as the mains, and only drop it 10dB when fed to channel 4 as the LFE channel is the only one that needs this drop
Well the level is the same as the mains. REW can't possibly know where the user is sending the signal and whether there's a 10dB boost somewhere in the signal flow or not. REW is a measuring tool that shows the difference between what has been sent out and what comes back in. It's up to the user to correctly interpret the readings.

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post #11182 of 11690 Old 08-26-2014, 02:19 PM
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Originally Posted by AustinJerry View Post
What you may be doing is using the "Speaker Cal" signal (see attached screen shot below) for the main speakers, and then the "Sub Cal" signal for the sub. I tested this out just now, and the "Sub Cal" signal output to the subs registers approximately 10dB lower than the "Speaker Cal" signal sent to the main speakers. This does not indicate a difference in the levels between mains and subs--it's just a difference in the REW signal. Is this what you are measuring?

FWIW, and re the part in bold, I don't believe there is any difference in the signal REW sends. To double check, I looked at what my audio device sees and this confirms there is no difference in levels (see pics). i.e. any difference is levels is down to your signal chain. I thought it might be important to clarify that given the confusion around levels in recent posts.

speaker cal
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post #11183 of 11690 Old 08-26-2014, 02:29 PM
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I thought I measured a difference, but I could be wrong. I am still somewhat confused by what HD is doing, and why setting speaker levels using the test tones is not good enough.

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post #11184 of 11690 Old 08-26-2014, 02:45 PM
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Quote:
Originally Posted by HDgaming42 View Post
I raise the volume knob on the subwoofer until it reads 75dB.
what sub do you have? that control is not typically a "volume knob" but simply adjusts the input sensitivity of the amp in the sub, i.e. it reduces the voltage received. It's generally not a good idea to use this to set the sub level, that's what your AVR SW trim is for. The sub control is to ensure that, at peak output, you don't clip the sub amp.

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Originally Posted by AustinJerry View Post
I am still somewhat confused by what HD is doing, and why setting speaker levels using the test tones is not good enough.
I'm with you on that one. I have reread the last few pages and I'm still confused.

FWIW @HDgaming42 it would really help if you were v precise about exactly what steps you took, I've read quite a few posts where levels are going up and down and I have no real idea which levels are being talked about any more. This makes it nigh on impossible to help you. At this point, I can't tell whether you just prefer a high level on the sub (which is not unusual) or something is fundamentally wrong in your setup/measurement technique/interpretation of measurements. A recap of your kit + the exact method you have used might help.
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post #11185 of 11690 Old 08-26-2014, 02:56 PM
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Quote:
Originally Posted by Alan P View Post
Hey HD, why don't you save yourself the headache and just set the levels with your AVRs internal test tones and an SPL meter (or REWs SPL meter)?? This is what I would do...and what I do.

Does your AVR have Audyssey? Any sort of auto-setup?? If so, why aren't you just using that? Do you not trust it??
No--just don't have the time ATM. A full 8-position measurement takes over 40 minutes. My free time right now is measured in 5-10 minute blocks.

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Originally Posted by markus767 View Post
Well the level is the same as the mains. REW can't possibly know where the user is sending the signal and whether there's a 10dB boost somewhere in the signal flow or not. REW is a measuring tool that shows the difference between what has been sent out and what comes back in. It's up to the user to correctly interpret the readings.
Fair enough. However over HDMI (what I'm currently using) it should have every idea as to what channel it is sending the signal to.

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Originally Posted by 3ll3d00d View Post
FWIW, and re the part in bold, I don't believe there is any difference in the signal REW sends. To double check, I looked at what my audio device sees and this confirms there is no difference in levels (see pics). i.e. any difference is levels is down to your signal chain. I thought it might be important to clarify that given the confusion around levels in recent posts.
More and more curious. So something in my chain is changing the levels...
Computer over HDMI to receiver. All trims are 0 in AVR. I can't imagine why there's a difference...

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Originally Posted by AustinJerry View Post
I thought I measured a difference, but I could be wrong. I am still somewhat confused by what HD is doing, and why setting speaker levels using the test tones is not good enough.
Is that what everyone here does? Foregoes REW for any level setting and just trusts their AVR's test tones? I'm asking quite sincerely. This surprises me, but if it's the accepted practice...

I will try the RTA method and report back later.
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post #11186 of 11690 Old 08-26-2014, 03:07 PM
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Originally Posted by HDgaming42 View Post
No--just don't have the time ATM. A full 8-position measurement takes over 40 minutes. My free time right now is measured in 5-10 minute blocks.
levels are (usually?) set by the 1st measurement, just take that one (or 3 in the same position if it makes you take 3, I forget) and see what it says. IIRC you can choose to discard the results before saving but maybe that is AVR specific.

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Originally Posted by HDgaming42 View Post
Fair enough. However over HDMI (what I'm currently using) it should have every idea as to what channel it is sending the signal to.
it just sees an (ASIO) audio device that has n channels. The fact the transport is HDMI & the target is an AVR that applies a 10dB boost to the 4th ASIO channel is neither here nor there to REW.

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Originally Posted by HDgaming42 View Post
Is that what everyone here does? Foregoes REW for any level setting and just trusts their AVR's test tones? I'm asking quite sincerely.
I would think the vast majority of people, even those who frequent this thread, use that method. Adjusting from this point is arguably more about preference than correctness.
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post #11187 of 11690 Old 08-26-2014, 03:14 PM
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Quote:
Originally Posted by HDgaming42 View Post
Is that what everyone here does? Foregoes REW for any level setting and just trusts their AVR's test tones? I'm asking quite sincerely. This surprises me, but if it's the accepted practice...

I will try the RTA method and report back later.
What we are trying to tell you is that there should not be any difference between setting levels with the internal test tones or by using REW. The fact that you are observing a difference indicates (to me at least) that there is a flaw in your procedure or your understanding. We have been trying to follow what you are doing, but so far we remain confused.

And if you have an AVR with Audyssey, my recommendation would be to run the calibration and let Audyssey set your levels. I have yet to see Audyssey make a mistake in setting speaker levels.

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post #11188 of 11690 Old 08-26-2014, 03:46 PM
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Quote:
Originally Posted by HDgaming42 View Post
No--just don't have the time ATM. A full 8-position measurement takes over 40 minutes.


Takes me about 15 minutes at most. That being said, I've had good results from just a 3 point calibration (1 - MLP / 2 - 3" left of MLP / 3 - 3" right of MLP)...takes about 5 minutes.

With all the time you've wasted trying to set your levels manually with REW you probably could have run full 8-point Audyssey a dozen times!

And, yes, I trust the levels set by Audyssey....and have verified them many, many times with an analog SPL meter and REWs SPL meter. I've ran Audyssey so many times in the last year, I've lost count.

The only thing I do is bump up the sub trim from where Audyssey sets them....my preference is hotter than most though at +8db.

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post #11189 of 11690 Old 08-26-2014, 03:48 PM
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Originally Posted by 3ll3d00d View Post
The fact the transport is HDMI & the target is an AVR that applies a 10dB boost to the 4th ASIO channel is neither here nor there to REW.
Ahhh, I get it. Thanks.

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Originally Posted by 3ll3d00d View Post
I would think the vast majority of people, even those who frequent this thread, use that method. Adjusting from this point is arguably more about preference than correctness.
Good to know.

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Originally Posted by AustinJerry View Post
What we are trying to tell you is that there should not be any difference between setting levels with the internal test tones or by using REW. The fact that you are observing a difference indicates (to me at least) that there is a flaw in your procedure or your understanding. We have been trying to follow what you are doing, but so far we remain confused.
There is confusion all around. First it was theorized that the error in my chain was that I was using the LFE channel, or Channel 4 as it were instead of Channels 1 & 2.

I switched to Channels 1 & 2 and I still see a discrepancy between my AVR and REW.

I was then told it might be because I was using "Sub Cal" which is 10dB lower.

Then I was told it was NOT because of using "Sub Cal" as it is NOT 10dB lower.

I completely understand that there SHOULDN'T be a difference between the AVR and REW. I clearly have much to learn about REW, but I try to explain what I've done--and what I'm seeing so as to elicit the best chance at getting accurate guidance.

I'm worried that if I'm missing something about the operation of REW, or if there is something messed up in my chain then further reliance on REW without sorting out either issue will result in me making things worse--not better.

I'd love to just trust my AVR and move on, but I'd like REW to be operating accurately. Everyone tells me there should be no difference and I agree that there shouldn't be. However there is a measurable difference. And a very precise 10dB at that.

I'm fine with just using my AVR for the initial level setting, but what use are doing REW sweeps, etc if something in my chain is throwing things off by 10dB? Clearly generating a signal out of REW into my AVR can't be trusted at the moment. Something is set incorrectly...somewhere.

It can't get much simpler than "set the levels using this process via the AVR" followed by comparing the SPL of the output of REW on a channel by channel basis. They don't agree. So I don't feel I can trust a) the signals being generated by REW b) the chain through which which those signals flow.

Very frustrating, and I appreciate all of your patience. If you've got questions, I'll answer them!
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post #11190 of 11690 Old 08-26-2014, 03:53 PM
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I think the best thing to do is simply clearly and simply state your signal chain, show your measurements with the 10dB settings and list your settings. Just state the facts basically. Fwiw I think it makes a lot of sense to get comfortable with exactly what is going on before you go further. There are many nooks and crannies in an AV setup after all
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