"Official" Audyssey thread Part II - Page 48 - AVS Forum | Home Theater Discussions And Reviews
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post #1411 of 7247 Old 10-17-2016, 01:58 PM
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Originally Posted by stash64 View Post
For me, the magnitude of the hiss has increased. I need to get my ear within a few inches of the tweeter to pick up the hiss when DEQ is off but, when on, I can hear the noise several feet away. In addition, I can hear a static-like noise similar to when an analog radio is not tuned in correctly and just picking up static... some of this noise is coming from the midrange. No hum. I've definitely heard ground loop noise in the past and this does not sound the same.
IMHO, you may need to submit a ticket to Marantz support to see if they have dealt with this issue. It does feel to me more like a hardware fault though.
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post #1412 of 7247 Old 10-17-2016, 02:07 PM
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I have a Marantz AV8801. I set the sub level to -11.5 after audyssey then increase it to -5.5 to get the bass I want. My question is which is the best way to set the speaker trims. I have crown amps with adjustable gains. With the gains up full I get -9.5. With the gains at half I get 0.0. Which would be the preferred method for setting speaker trims, amp gain on full, half or 3/4.
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post #1413 of 7247 Old 10-17-2016, 02:32 PM
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Originally Posted by mogorf View Post
Hi Selden,

Was there also a fix offered for those complaints in other threads? Would be interesting to see some conclusions.
The only workaround that I'm aware of is to use preamp outputs and install attenuators between them and external amps. This forces the receiver or prepro to output a higher signal level, resulting in a better signal-to-noise ratio. Of course, this can't be used if a receiver's internal amps are all that are available.
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On another note as I know Audyssey and its features are purely software based, while noise is particularly hardware related. In other words if Audyssey casuses noise its usually a kinda "garbage in garbage out" issue.
Audyssey runs on DSPs. Digital switching noise is generated by all digital circuits and picked up by analog circuits when the transistors in the digital circuits change state (switch on and off), as when Audyssey's algorithms are running. It could be that the "bypass capacitors" (the filter capacitors on the power leads of the DSP chips) are simply too small.
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Lastly, just to be absolutely sure: are we talking about hiss or hum? As we know hiss is like "ssshhh" or like wind blowing, while hum is usually caused by a ground loop (or the like) and its a 50Hz/60 Hz tone depending on where we live (Europe or N.America).
. It's a hiss. You can hear it yourself if you put your ears close to the tweeters of your speakers.

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post #1414 of 7247 Old 10-17-2016, 02:34 PM
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Originally Posted by jbjbjbjb View Post
I have a Marantz AV8801. I set the sub level to -11.5 after audyssey then increase it to -5.5 to get the bass I want. My question is which is the best way to set the speaker trims. I have crown amps with adjustable gains. With the gains up full I get -9.5. With the gains at half I get 0.0. Which would be the preferred method for setting speaker trims, amp gain on full, half or 3/4.
Lower trim levels are desirable so that there's more overhead available to handle loud passages, as when there's an explosion in the soundtrack.

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post #1415 of 7247 Old 10-17-2016, 02:43 PM
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Originally Posted by Selden Ball View Post
Audyssey runs on DSPs. Digital switching noise is generated by all digital circuits and picked up by analog circuits when the transistors in the digital circuits change state (switch on and off), as when Audyssey's algorithms are running. It could be that the "bypass capacitors" (the filter capacitors on the power leads of the DSP chips) are simply too small.
Agree with that, but in case the filter capacitors on the power leads of the DSP chips are simply too small that would mean all the Marantz of the same model would have this unwanted hiss. IMHO, this is an individual issue best discussed with Marantz support team, no?
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post #1416 of 7247 Old 10-17-2016, 02:44 PM
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Originally Posted by mogorf View Post
Agree with that, but in case the filter capacitors on the power leads of the DSP chips are simply too small that would mean all the Marantz of the same model would have this unwanted hiss. IMHO, this is an individual issue best discussed with Marantz support team, no?
My impression is that all D+M equipment have this hiss. Only the people who have highly efficient speakers notice it.

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post #1417 of 7247 Old 10-17-2016, 02:51 PM
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Originally Posted by Selden Ball View Post
My impression is that all D+M equipment have this hiss. Only the people who have highly efficient speakers notice it.
stash64 said his Jamo C809's are about average on efficiency at 89 dB.

More troubleshooting could be done by disconnect all signal wiring from the Marantz while keeping the speakers connected. Does the hiss persist with only the amp in stand alone configuration with speakers attached while toggling between DEQ on/off?
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post #1418 of 7247 Old 10-17-2016, 02:53 PM
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Originally Posted by Selden Ball View Post
My impression is that all D+M equipment have this hiss. Only the people who have highly efficient speakers notice it.
In recent years, I have only had Denon AVRs along with what I would consider highly efficient speakers...105dB 1w/1m, then 98dB 1w/1m. I have never heard hiss or static at the kind of levels the OP is talking about.

I would agree that there has to be something wrong with his AVR.
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post #1419 of 7247 Old 10-17-2016, 03:16 PM
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I re-ran the Audyssey but this time it was on Saturday midnight. The environment was quiet, I covered my coffee table (which is just before my couch) with a blanket and put a thick towel on my couch as well. I did all 8 readings each about 2 feet apart from MLP. I think I got a good reading this time and it is sounding really good now. I can sense that it has done something to the treble curve a bit but I am liking it. It feels more balanced out with the bass. The distance it measured was almost accurate! The filters applied also seems well matched (40 for my towers, 60 for my center, 80 for surrounds, 100-110 for AE modules). I have two subs (out of one is a sealed one which I use for music also and cross over is set at a lower point) and it has done a good job balancing between the two diff subs too. All in all I am satisfied and it was more than what I expected. Thanks for all the inputs in this thread.
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post #1420 of 7247 Old 10-17-2016, 04:38 PM
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In recent years, I have only had Denon AVRs along with what I would consider highly efficient speakers...105dB 1w/1m, then 98dB 1w/1m. I have never heard hiss or static at the kind of levels the OP is talking about.

I would agree that there has to be something wrong with his AVR.
My speakers average ~ 96db efficiency (or sensitivity) in-room, and I have never experienced an audible hissing problem with my Marantz either. I don't hold out great hope for Marantz tech support being able to assist much in terms of advice, though. I would try a microprocessor reset first, and only if the problem is really bothersome, try to send the unit back for repair or exchange.

Although Sean noted that DEQ might be really useful to him at low volume levels, he might still try workarounds, such as various RLO settings, or the use of tone controls, depending on how bothersome the hiss really is. Sending off my AVR is sort of a last resort for me.
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Speaker placements & Room treatments; HT calibration & Room EQ; Room gain; Bass
Preferences; Subwoofer Buyer's Guide: Sealed/ported; ID subs; Subwoofer placement.
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post #1421 of 7247 Old 10-17-2016, 04:48 PM
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Originally Posted by JaytheDreamer View Post
I re-ran the Audyssey but this time it was on Saturday midnight. The environment was quiet, I covered my coffee table (which is just before my couch) with a blanket and put a thick towel on my couch as well. I did all 8 readings each about 2 feet apart from MLP. I think I got a good reading this time and it is sounding really good now. I can sense that it has done something to the treble curve a bit but I am liking it. It feels more balanced out with the bass. The distance it measured was almost accurate! The filters applied also seems well matched (40 for my towers, 60 for my center, 80 for surrounds, 100-110 for AE modules). I have two subs (out of one is a sealed one which I use for music also and cross over is set at a lower point) and it has done a good job balancing between the two diff subs too. All in all I am satisfied and it was more than what I expected. Thanks for all the inputs in this thread.
Hi Jay,

Congratulations on a good sounding calibration. It can take a little effort, but the results are usually worth it. One change I might suggest, though, is to raise your crossovers on your fronts, and center, to 80Hz for a while, and see how that sounds. If you like, you can always drop your fronts down to 60Hz, if you want to experiment, once you have a listening baseline established at 80Hz.

As a general rule, it is a good idea to set your speakers to 1/2 or 1 octave higher than the crossover set by your AVR, to give them some extra headroom during loud, bass heavy, passages in movies. That is particularly the case with crossovers under 80Hz. In the case of your fronts, 60Hz would be 1/2 octave, and 80Hz would be 1 octave. I would probably raise and keep the CC at 80Hz, in any case, but I might experiment with 60Hz on the fronts, after trying 80Hz for a while.

Regards,
Mike

Just as an additional note for completeness sake, you can always raise your crossovers from wherever Audyssey and your AVR set them, and you can go back and forth to experiment. But, in general, you would not want to lower the crossovers below where they were set by your AVR.

GUIDE TO SUBWOOFER CALIBRATION AND BASS PREFERENCES

* The Guide linked above is a comprehensive guide to Audio & HT systems, including:
Speaker placements & Room treatments; HT calibration & Room EQ; Room gain; Bass
Preferences; Subwoofer Buyer's Guide: Sealed/ported; ID subs; Subwoofer placement.

Last edited by mthomas47; 10-17-2016 at 05:01 PM.
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post #1422 of 7247 Old 10-17-2016, 05:24 PM
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Originally Posted by Selden Ball View Post
FWIW, it's my understanding that fixed level background noise, the kind that isn't affected by the volume control knob, can be particularly noticeable if you have high efficiency speakers. Audyssey reduces the signal gain to compensate for the the speaker gain but the noise level stays the same. As a result, the signal-to-noise ratio becomes worse.

I've also seen quite a few complaints from people in other threads about the increased noise level introduced when Audyssey is enabled.
Also FWIW, I have super efficient corner horn speakers (rumored to be 98 dB/2.83v/1m anechoic when using AES standards, which, arguably, are inappropriate because they are not in keeping with the design parameters of these particular speakers, and 105 dB/2.83v/1m in the design required 1/8 space in a chamber that is anechoic starting 4 feet out from the special wooden corner in the chamber). I have had two components that might have been fine with speakers of the probable typical efficiency of 90 dB/2.83v/1m that hissed like ... uh ... crazy ... through my corner horns, but, with my current equipment (Marantz pre/pro, NAD power amps, OPPO player) no hiss is audible from the MLP, with or without Audyssey, even though Audyssey turned up the treble above 1.5K Hz by an average of 5 dB over the "without Audyssey" condition, smoothed the response significantly, and increased clarity appreciably...
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post #1423 of 7247 Old 10-17-2016, 07:04 PM
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Originally Posted by mthomas47 View Post
Hi Jay,

Congratulations on a good sounding calibration. It can take a little effort, but the results are usually worth it. One change I might suggest, though, is to raise your crossovers on your fronts, and center, to 80Hz for a while, and see how that sounds. If you like, you can always drop your fronts down to 60Hz, if you want to experiment, once you have a listening baseline established at 80Hz.

As a general rule, it is a good idea to set your speakers to 1/2 or 1 octave higher than the crossover set by your AVR, to give them some extra headroom during loud, bass heavy, passages in movies. That is particularly the case with crossovers under 80Hz. In the case of your fronts, 60Hz would be 1/2 octave, and 80Hz would be 1 octave. I would probably raise and keep the CC at 80Hz, in any case, but I might experiment with 60Hz on the fronts, after trying 80Hz for a while.

Regards,
Mike

Just as an additional note for completeness sake, you can always raise your crossovers from wherever Audyssey and your AVR set them, and you can go back and forth to experiment. But, in general, you would not want to lower the crossovers below where they were set by your AVR.
Thanks Mike, Im making my fronts to 60 and CC to 80 for few days and would see how it is. With my previous AVR everything was at 80 but this time Audyssey did a technically better job, but I would agree with giving head room to the speakers and making use of my two subs when needed. I will post my impressions.

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post #1424 of 7247 Old 10-17-2016, 07:13 PM
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Boy... it's getting hard to keep up with all the suggestions/analysis/speculation... I've created a monster.

Anyway, I will check with Marantz this week and hopefully be able to report back with some useful information. I did ask other owners (on the AV7702 thread) if they could check the effect of DEQ on their system but I've only heard back from one person so far.

I must say that I have always heard some small amount of tweeter hiss on every set up I have ever owned and usually I have to get within about 6 inches (or closer) of the tweeter to hear the hiss. To me, this is perfectly acceptable and normal.

Just to summarize, the increased hiss plus static sound can be heard up to about 8 feet away under the following conditions:
  • AVP set to any source and any input (optical, coax, HDMI, analog... does not matter)
  • Source is on but no playback or playing back and there is a silent section in the music. The noise still exists during playback but of course the music will cover up the noise. If the source is off, no extra noise.
  • Audyssey and DEQ set to On. If DEQ is off, there is no extra noise no matter any other variables.
  • AVP set to a surround mode, not stereo. DTS Neural X is the worst. Setting to stereo with DEQ on results in only a very small increase in hiss and no static noise.
  • The extra noise is primarily observed in my front tower speakers (set to large) with no sub in the system. My center and surrounds are set to small and there is only a small increase in noise in these three speakers with DEQ on.


I think that sums it up. Thanks again to all for the help. I will definitely check back in if there are any light bulb moments or if Marantz can shed some light. I agree with Mike though and will try a reset before sending the unit to Marantz.
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post #1425 of 7247 Old 10-18-2016, 01:11 AM
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Originally Posted by JaytheDreamer View Post
I re-ran the Audyssey but this time it was on Saturday midnight. The environment was quiet, I covered my coffee table (which is just before my couch) with a blanket and put a thick towel on my couch as well. I did all 8 readings each about 2 feet apart from MLP. I think I got a good reading this time and it is sounding really good now. I can sense that it has done something to the treble curve a bit but I am liking it. It feels more balanced out with the bass. The distance it measured was almost accurate! The filters applied also seems well matched (40 for my towers, 60 for my center, 80 for surrounds, 100-110 for AE modules). I have two subs (out of one is a sealed one which I use for music also and cross over is set at a lower point) and it has done a good job balancing between the two diff subs too. All in all I am satisfied and it was more than what I expected. Thanks for all the inputs in this thread.
I've got a coffee table between my setup and the measuring position and I've taken to actually removing it from the room while running the setup process and then bringing it back afterwards. I've found I get a better result without the table in position during the measurement process.
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post #1426 of 7247 Old 10-18-2016, 05:25 AM
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I've got a coffee table between my setup and the measuring position and I've taken to actually removing it from the room while running the setup process and then bringing it back afterwards. I've found I get a better result without the table in position during the measurement process.

Interesting. I've always thought the room should be kept exactly as it would be when listening, except no bodies (human) of course. That way Audyssey can pick up on all the reflections. I've also thought someone should develop a microphone dummy... essentially a human doll that can sit upright and is made with the correct density (ballistic) material and a place to stick a microphone in the head, right between the ears.
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post #1427 of 7247 Old 10-18-2016, 08:15 AM
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I've got a coffee table between my setup and the measuring position and I've taken to actually removing it from the room while running the setup process and then bringing it back afterwards. I've found I get a better result without the table in position during the measurement process.
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Interesting. I've always thought the room should be kept exactly as it would be when listening, except no bodies (human) of course. That way Audyssey can pick up on all the reflections. I've also thought someone should develop a microphone dummy... essentially a human doll that can sit upright and is made with the correct density (ballistic) material and a place to stick a microphone in the head, right between the ears.
FWIW, this idea of keeping the room exactly the same has always been a somewhat controversial issue. In general, I think it's a good idea to adhere to the idea of not changing the room between calibration and playback. But, on the other hand, the ultimate objective of running room EQ is to achieve improved sound quality. So, if putting a cover over a table (and then removing it later) as Jay did, or removing the table from the room (and then returning it) as David did, actually results in improved SQ, who's to say that's wrong? When general theory conflicts with practical application, I lean toward the actual result, rather than the theory.

I think that the advice given to people who inquire on the thread should remain the same: keep the room essentially the same way during calibration that it will be during playback (with exceptions for putting a blanket over a sofa, for instance). But, if people subsequently experiment, and discover some specific procedure that seems to work well in their rooms, to me that falls pretty clearly into the category of YMMV.

Incidentally, the ballistic dummy idea has been talked about, and joked about before, but it's not really necessary and would create it's own problems. Using multiple mic positions, sound would bounce off the dummy, and into the Audyssey mic, in the same way that it would from the back of a sofa. For the most part, our binaural hearing, and the way that our brains interpret and correlate sounds, is sufficiently different from the way the Audyssey microphone "hears" sounds that the close reflections don't present a problem during actual listening sessions. We just need to prevent them from presenting a problem to the Audyssey microphone.

Regards,
Mike
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post #1428 of 7247 Old 10-18-2016, 09:47 AM
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Interesting. I am primarily an Audio guy, playing music most of the time. My room is treated a little bit (bass traps on corners, panels on first reflection points, measured front tower positions from walls, tow angle and bass crawl experimented and have a good sounding system, etc). I never did any electronic calibration before. I added this freaking surround setup later (until then life was peaceful ). As my place is not huge and have to accommodate stuff for family I cannot do experiments with something removed from the room. I also have a similar opinion as of Mike to let everything in place as it would be when you do a calibration, though any kind of experimentation is always good as he pointed out. I am saying this from years of practical experience with 2 channel audio. Even a slight change of angle, placement, a new small rug, a heavy curtain, a furniture can alter sound. Even last week I sensed my right channel was sounding a bit odd and found somebody caused the right tower to turn few degrees outwards, luckily I have marked the positions and was able to put the speaker back to its place (though it was only an inch and may be less than 5 degrees of angle changed). Anyway I am happy I got a good sound now. This is one of the most interesting threads in AVS Waiting for more and more experiments!
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post #1429 of 7247 Old 10-18-2016, 11:15 AM
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Originally Posted by JaytheDreamer View Post
Interesting. I am primarily an Audio guy, playing music most of the time. My room is treated a little bit (bass traps on corners, panels on first reflection points, measured front tower positions from walls, tow angle and bass crawl experimented and have a good sounding system, etc). I never did any electronic calibration before. I added this freaking surround setup later (until then life was peaceful ). As my place is not huge and have to accommodate stuff for family I cannot do experiments with something removed from the room. I also have a similar opinion as of Mike to let everything in place as it would be when you do a calibration, though any kind of experimentation is always good as he pointed out. I am saying this from years of practical experience with 2 channel audio. Even a slight change of angle, placement, a new small rug, a heavy curtain, a furniture can alter sound. Even last week I sensed my right channel was sounding a bit odd and found somebody caused the right tower to turn few degrees outwards, luckily I have marked the positions and was able to put the speaker back to its place (though it was only an inch and may be less than 5 degrees of angle changed). Anyway I am happy I got a good sound now. This is one of the most interesting threads in AVS Waiting for more and more experiments!
Jay,

I agree that this has been one of the most consistently interesting threads on the forum. I started reading here long before I started contributing. Like yourself, I was always more of an audio guy, and I didn't even take HT very seriously until about 10 years ago. My learning curve really took off though with HT and Audyssey. Some of the fundamental concepts that we learned in two-channel and quadraphonic stereo are still perfectly applicable to our modern systems, but subwoofers, surround channels, and automated room EQ have definitely made our systems (and lives) more complicated. And, also infinitely more interesting from an AV standpoint.

GUIDE TO SUBWOOFER CALIBRATION AND BASS PREFERENCES

* The Guide linked above is a comprehensive guide to Audio & HT systems, including:
Speaker placements & Room treatments; HT calibration & Room EQ; Room gain; Bass
Preferences; Subwoofer Buyer's Guide: Sealed/ported; ID subs; Subwoofer placement.
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post #1430 of 7247 Old 10-18-2016, 11:32 AM
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Thanks Mike. I have a question (rather I need a confirmation to make sure my understanding is correct). This is about Dynamic EQ and the Reference level. After reading many articles, forum answers etc I assume the following.

The reference level value we provide is simply telling Audyssey what content we are playing and at what levels they were mixed, right? If we set 0db, then we are telling the level is for movies and as we go up (5,10,15), we are telling Audyssey that the content we are playing has reference levels higher and do less compensation. So if I set it 15db and play a movie, since Audyssey sees the 15db reference so it wouldn't apply much of the compensation thinking the content doesn't have too much to compensate as it is more packed with higher volumes while if I set it to 0db and play a loud hip/hop, it would still compensate and add unnecessary boost to some frequencies. If my assumption is correct, what could be a good reference level value for most of the TV/Show content? Or is there a best setting for TV/Shows/Movies (not including music anyway)?

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Thanks Mike. I have a question (rather I need a confirmation to make sure my understanding is correct). This is about Dynamic EQ and the Reference level. After reading many articles, forum answers etc I assume the following.

The reference level value we provide is simply telling Audyssey what content we are playing and at what levels they were mixed, right? If we set 0db, then we are telling the level is for movies and as we go up (5,10,15), we are telling Audyssey that the content we are playing has reference levels higher and do less compensation. So if I set it 15db and play a movie, since Audyssey sees the 15db reference so it wouldn't apply much of the compensation thinking the content doesn't have too much to compensate as it is more packed with higher volumes while if I set it to 0db and play a loud hip/hop, it would still compensate and add unnecessary boost to some frequencies. If my assumption is correct, what could be a good reference level value for most of the TV/Show content? Or is there a best setting for TV/Shows/Movies (not including music anyway)?
Jay,

I am not sure I understood the questions exactly, but I'll try anyway. After an Audyssey calibration, Reference on your system will be exactly 0.0 MV. At any master volume (MV) from -5 down, DEQ will apply a bass/treble boost. That boost will be greater (about +2db for every 5db below Reference) as you go down in MV. So, DEQ will boost more at -10 MV than it will at -5 MV, and so on. At 0.0 MV, DEQ will be neutral, and will not do anything. At +5 MV, DEQ will subtract ~2db of bass/treble. And so on, as you go further up in volume.

But, listening at 0.0 MV in a normal size room could be very hard on your hearing, if done for prolonged periods, and very few HT systems would even allow you to play without significant distortion at levels of +5 MV, even if your hearing could tolerate it. Most people on the forum probably watch 5.1 movies at an average volume of about -20 to -10. That has been pretty consistently used as an average range on the forum. In a normal room or HT (below about 20,000^3) -5 is probably equivalent to Reference (0.0) in a movie theater, due to sound reinforcement from the room. Small rooms amplify the SPL in a way that very large rooms don't. Even in full-sized cinemas, most movies played in theaters are also probably not played quite at Reference, simply because most people don't like the sound that loud. Exceptions to that may be IMAX theaters.

TV shows, sports programs, and music are played at variable volumes depending on the individual. But, based on my personal observation of what people report, I would guess that most people listen to music (and watch TV) at lower volumes than they use for feature length 5.1 movies. So, if the average movie MV is about -15, then the average for TV and music would be even lower than that. Of course, there would be exceptions, depending on both the type of music and the individual in question, but I would say that on average, most people watch movies at higher volumes than TV and music. I hope this helps to answer your questions.

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Mike

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post #1432 of 7247 Old 10-18-2016, 03:03 PM
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Interesting. I've always thought the room should be kept exactly as it would be when listening, except no bodies (human) of course. That way Audyssey can pick up on all the reflections. I've also thought someone should develop a microphone dummy... essentially a human doll that can sit upright and is made with the correct density (ballistic) material and a place to stick a microphone in the head, right between the ears.
I'll second Mike's response but add a couple of comments.

First, keeping the room exactly as it is when listening is a bit of a problem if it's not always the same way when listening. My system is in an open plan area and I live in a sub-tropical area. There are doors to rooms leading off the area and there's a large glass sliding door to a patio. In summer I tend to have the patio door open at night to cool the house down but in winter it's shut in order to keep warmth in. The doors leading to other rooms are open or closed depending on circumstances. Rugs get left on the sofa during winter and put away in summer. The window opens or closes depending on the weather and I open or close the blinds and curtains depending on light and the state of the windows and doors.

Audyssey only stores 1 set of measurements. Sure, I can save measurements to the computer, create several different setting files, and swap between them by running a restore process but that's a pain if all you want to do is to open or close a couple of doors and a window for the evening and then reopen them the next day.

Basically having things "exactly as they are when listening" is a bit of a myth because the way they are when listening varies on a pretty regular basis for probably most of us. It's easier to achieve that if you have a dedicated HT room but if you have your system in the living room things that affect the room response are likely to change once or twice each day.

So, having my system in a space where things change a couple of times each day, over time I've done the setup process with things in the room one way and things another way, and I've developed a "gut feel" if you want to call it that for things which affect my results. I've developed a list of things I do in the room before running setup because I've discovered that doing those things means I can consistently get a result I like which will work well regardless of the changes I make with the way things are in the room every day. It's a compromise solution.

If Audyssey allowed me to store several different results on the AVR and swap between them via a menu, I'd use that and do several setup processes which involved having things in the room set up in different ways that reflected how they are when I listen at various times but I can't store different results and swap between them via a menu so I go for a compromise and the way things are when I measure is probably the way they are least often when I listen but it delivers results I'm comfortable with however the room is set up from time to time.

Second, let's say you follow the instructions perfectly. You invite your friends over and have a night listening to something and some of them tell you things sound great but there's probably going to be one friend who tells you you need a bit more or less bass and another who wants the highs turned up or down. Not everyone is going to be satisfied by the result Audyssey delivers and you may even be the person who wants a bit more or less bass or treble. We can change the result by changing some settings and you may be able to find something you prefer by doing that. You can change the result by changing something that affects the results of the measurement process and you may be able to find something you prefer by doing that. Some people do a bit of both. You need to ask yourself what you're doing when you set up your system. Is your goal to get a result that conforms to some other person's idea of a good response, or is your goal to get a result that you personally enjoy? If your goal is the first of those, run Audyssey and don't change a thing. If your goal is the second, then run Audyssey and if the result isn't quite what you prefer, then play with settings or the room setup during measurement, or the mic placement pattern, or the number of measurements you run until you get a result you're happy with. It's your system and you're the one in charge, and the only person you have to satisfy is you. If you're happy with the result you get, great, If you're not happy with the result you get, then the sensible thing is to do something different and get a result you're happy with, not just accept the result you're unhappy with and live with it because that's the way things turned out.

Third, over time there's a lot of questions raised about the setup process and how people do it, and there's more than a few people here who have done different things. I never thought of running a tight mic pattern until I read about it here. I tried it and went back to a wider mic pattern. I've tried 3, 5 and 8 measurements and I've ended up settling on 8. I've tried things that some people have suggested and gone back to doing it the way the instructions suggest. I've tried doing other things the way someone else suggested and ended up continuing to do them that way. Removing the coffee table during measurements was one of those things. We had someone discovering recently that putting a piece of tissue paper over the tweeter helped him get a result he preferred. I haven't tried that but I have tried having the speaker grilles on and off during the measurement process. You don't have to try everything and if you do try some things then not all of them will work or help or whatever you want to call it but one or two of them may. Don't bother experimenting if you're happy but if you aren't quite happy or if you just want to play and see how things may change, then experiment and keep what works for you and discard what doesn't.
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Jay,

I am not sure I understood the questions exactly, but I'll try anyway. After an Audyssey calibration, Reference on your system will be exactly 0.0 MV. At any master volume (MV) from -5 down, DEQ will apply a bass/treble boost. That boost will be greater (about +2db for every 5db below Reference) as you go down in MV. So, DEQ will boost more at -10 MV than it will at -5 MV, and so on. At 0.0 MV, DEQ will be neutral, and will not do anything. At +5 MV, DEQ will subtract ~2db of bass/treble. And so on, as you go further up in volume.

But, listening at 0.0 MV in a normal size room could be very hard on your hearing, if done for prolonged periods, and very few HT systems would even allow you to play without significant distortion at levels of +5 MV, even if your hearing could tolerate it. Most people on the forum probably watch 5.1 movies at an average volume of about -20 to -10. That has been pretty consistently used as an average range on the forum. In a normal room or HT (below about 20,000^3) -5 is probably equivalent to Reference (0.0) in a movie theater, due to sound reinforcement from the room. Small rooms amplify the SPL in a way that very large rooms don't. Even in full-sized cinemas, most movies played in theaters are also probably not played quite at Reference, simply because most people don't like the sound that loud. Exceptions to that may be IMAX theaters.

TV shows, sports programs, and music are played at variable volumes depending on the individual. But, based on my personal observation of what people report, I would guess that most people listen to music (and watch TV) at lower volumes than they use for feature length 5.1 movies. So, if the average movie MV is about -15, then the average for TV and music would be even lower than that. Of course, there would be exceptions, depending on both the type of music and the individual in question, but I would say that on average, most people watch movies at higher volumes than TV and music. I hope this helps to answer your questions.

Regards,
Mike
Here is my understanding (or misunderstanding) of the reasonable recommendation by THX and others to use a Main Volume level below Reference in a small (i.e., home size) room. While its true that smaller rooms increase the physical intensity of the sound, they shouldn't after Audyssey gets through with them. After Audyssey (or similar, professional) calibration to Reference Level is done in any room, small or large, they should have the same SPL, if everything worked correctly. Audyssey will have taken into account the reinforcing nature of the small room ("room gain"), and adjusted the volume to make the maximum peak SPL ("full scale") 105 dB from each regular speaker, and 115 dB from the sub, no matter what the room size. I think that's Reference Level, period. Any increased intensity due to small room size is turned down by Audyssey calibration until the test tones produce Referenc Level. But, small rooms have many early reflections, and are small enough to have standing waves within the audible spectrum. Both can be unpleasant --- unpleasant enough to sound "louder" than Reference to the human perceptual mechanism, but not to a microphone hooked to a standardized measuring device. Some of the early reflections in a home theater can be early enough to seem to be part of the original sound coming out of the speakers, and can alter the apparent frequency characteristics of a speaker. These early, often specular, reflections may well sound like unpleasant increases in SPL, just as increased distortion makes music sound louder. So, to cook up a worst case, if one were to put a high distortion amplifier in the line, and have many early and specular reflections in the room, everyone would agree that it sounds louder, even if we had adjusted the SPL to be the same. If that same SPL occurred in both a small and large room, most people would say that it was "louder" in the small, reflective room. So, on the average, the MV in smaller rooms should be set somewhere below where Audyssey sets it (Reference Level), not because the SPL would otherwise be too high, but because it sounds too loud at Reference Level in most small rooms.

Indeed, SPL comes from the world of physics, while "loudness" is a perceptual phenomenon, dependent on many factors. "Volume" originally referred to ... well, volume. The AV equipment and radios of the early 20th Century had a control marked "volume" to adjust to room size. The same SPL in a living room or a big hall would require very different volume control settings, because those rooms were of very different volumes.
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Here is my understanding (or misunderstanding) of the reasonable recommendation by THX and others to use a Main Volume level below Reference in a small (i.e., home size) room. While its true that smaller rooms increase the physical intensity of the sound, they shouldn't after Audyssey gets through with them. After Audyssey (or similar, professional) calibration to Reference Level is done in any room, small or large, they should have the same SPL, if everything worked correctly. Audyssey will have taken into account the reinforcing nature of the small room ("room gain"), and adjusted the volume to make the maximum peak SPL ("full scale") 105 dB from each regular speaker, and 115 dB from the sub, no matter what the room size. I think that's Reference Level, period. Any increased intensity due to small room size is turned down by Audyssey calibration until the test tones produce Referenc Level. But, small rooms have many early reflections, and are small enough to have standing waves within the audible spectrum. Both can be unpleasant --- unpleasant enough to sound "louder" than Reference to the human perceptual mechanism, but not to a microphone hooked to a standardized measuring device. Some of the early reflections in a home theater can be early enough to seem to be part of the original sound coming out of the speakers, and can alter the apparent frequency characteristics of a speaker. These early, often specular, reflections may well sound like unpleasant increases in SPL, just as increased distortion makes music sound louder. So, to cook up a worst case, if one were to put a high distortion amplifier in the line, and have many early and specular reflections in the room, everyone would agree that it sounds louder, even if we had adjusted the SPL to be the same. If that same SPL occurred in both a small and large room, most people would say that it was "louder" in the small, reflective room. So, on the average, the MV in smaller rooms should be set somewhere below where Audyssey sets it (Reference Level), not because the SPL would otherwise be too high, but because it sounds too loud at Reference Level in most small rooms.

Indeed, SPL comes from the world of physics, while "loudness" is a perceptual phenomenon, dependent on many factors. "Volume" originally referred to ... well, volume. The AV equipment and radios of the early 20th Century had a control marked "volume" to adjust to room size. The same SPL in a living room or a big hall would require very different volume control settings, because those rooms were of very different volumes.
Gary,

I enjoyed reading your viewpoint on Reference volume, and I thought that you made several good observations. I particularly liked what you were saying about the impact of early (and late) reflections on perceived loudness. I think it is important to have a nominal Reference standard, even though we know that the standard is a maximum, and that not all movies are actually recorded using peak volumes of 105db for the regular channels and 115db for the LFE channel.

And, I also think it is important to try to explain Reference in simple terms, which I did in my post above, whenever someone asks on the thread about the relationship between Reference and Audyssey. But, in reality, the concept of an absolute Reference standard in cinematic production, much less in home theater, is much more complicated than that. Frankly, I among others, believe that Reference volume is a chimera--useful, but never the absolute that it is often taken to be. There was a recent thread on Reference volume in which I posted the following:

"I was late to this party, but enjoyed reading the discussion. There have been other threads in which several film mixers have stated that 0.0 MV (Reference), for movies they have mixed, sounds loud to them in their personal home theaters. This is for the small room effect reasons observed by Holman, and cited by LTD02. They consequently said that they usually watch movies at about -5 MV.

One additional point which has been skirted, but not addressed directly, is the difference between the sum of 7 speakers playing at 0.0 MV, and only 5 speakers. A 7.1 system should measure slightly louder at the MLP, than a 5.1 system, at the same MV, in the same room. I believe I remember reading that the difference would be about 2db.

I particularly liked Mark Seaton's post, and LTD02's posts, that explained that Reference volumes are actually a bit of a chimera in home theaters, depending as they do on so many variables, including things like size of room, room treatments, bass boost, and number of speakers. The Reference standard gives us a great starting point in calibrating our systems, and understanding their objective capabilities. But it is doubtful if any random two of us, listening at exactly the same MV setting in our respective home theaters, would measure, or perceive, exactly the same SPL."


Toole, Holman and others, have written about small room effects, which magnify SPL, and not simply the perception of SPL. And there are multiple variables which affect Reference level as any kind of absolute number. Audyssey is a useful tool for approximating Reference, but it is just an approximation. That is for at least two reasons which are independent of the room itself. The first reason is that Audyssey is measuring the SPL of each speaker individually, based on a roughly 75db test tone. But, Audyssey is never measuring the sum of the speakers in a system. And, the sum of the speakers in a system (each playing at an individual level of 75db) will be louder than 75db. Most audio experts I have read on the subject, attribute about +1db for each additional speaker in a system. So, a 5.1 system, calibrated with a 75db test tone, would natively play louder than a 2.1 system, at a Reference volume of 0.0 MV, and so on.

The second reason that Audyssey can only approximate Reference, irrespective of individual room factors, is the Audyssey microphone itself, which has an error factor of about +/- 3db. So, when Audyssey plays a 75db test tone, the Audyssey microphone could register that tone as low as ~72db, and boost every channel in a system accordingly, or the microphone could register the tone as high as ~78db, and cut every channel in a system accordingly. This has never been perceived as a problem, because the Audyssey microphone would be operating consistently for all of the channels, and would be achieving its intended goal of making each channel play at the same volume at the MLP. We also typically accept that an in-room Reference setting is really only an approximation anyway, and not an absolute number.

And then to name another major variable, which is independent of the Audyssey calibration, what about a bass boost? Any user who is boosting his subs above the nominal Audyssey setting is automatically playing at above Reference levels, relative to the other channels in a system. Some of that boost will be at frequencies which most SPL meters will have a tough time registering (depending on the type of sub, for instance) but the increase in total SPL will nevertheless be real. And, according to Holman, Toole, and others, that rising curve on the low-end is not only preferred by the vast majority of users, it is a natural result of the Equal Loudness Contours. Human hearing is simply not as acute in the very low frequencies, and more SPL is required to make those frequencies audible. It is entirely possible that some people hear those low frequencies more or less acutely than others do, and it is also entirely possible (highly likely, in fact) that some people enjoy hearing more bass than other listeners do. But if we increase the sub trim, the SPL is there, whether the individual listener entirely registers it all or not.

If anyone is interested in reading a really good discussion of Reference volumes, this is a link to the thread I mentioned:

https://www.avsforum.com/forum/155-di...l#post47134873

Regards,
Mike

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post #1435 of 7247 Old 10-19-2016, 11:38 AM
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The concept of "Reference Volume" playback is made irrelevant by the simple fact that not all movie soundtracks are encoded at the same volume level on disc (or streaming, etc.). Most movies that have Dolby sound formats utilize DialNorm, which will typically reduce the overall volume to all channels by 4dB. Meanwhile, DTS sound formats don't use DialNorm. In 99 cases out of 100, a movie with a DTS-HD Master Audio track will play louder than a movie with a Dolby TrueHD track, even at the same Master Volume setting on the receiver. In order to accurately compare the two, you have to raise the MV up 4dB when playing the Dolby track.

And that's just the general rule of thumb. There are plenty of oddball exceptions where a particular movie soundtrack will be encoded extra high or extra low. For example, The DTS-HD MA track on Avengers: Age of Ultron is set something like 10dB lower than any other soundtrack of a comparable movie.

You can't just set your receiver to 0dB and assume that everything you listen to will be so-called "Reference Volume." It's not that simple.

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The concept of "Reference Volume" playback is made irrelevant by the simple fact that not all movie soundtracks are encoded at the same volume level on disc (or streaming, etc.). Most movies that have Dolby sound formats utilize DialNorm, which will typically reduce the overall volume to all channels by 4dB. Meanwhile, DTS sound formats don't use DialNorm. In 99 cases out of 100, a movie with a DTS-HD Master Audio track will play louder than a movie with a Dolby TrueHD track, even at the same Master Volume setting on the receiver. In order to accurately compare the two, you have to raise the MV up 4dB when playing the Dolby track.

And that's just the general rule of thumb. There are plenty of oddball exceptions where a particular movie soundtrack will be encoded extra high or extra low. For example, The DTS-HD MA track on Avengers: Age of Ultron is set something like 10dB lower than any other soundtrack of a comparable movie.

You can't just set your receiver to 0dB and assume that everything you listen to will be so-called "Reference Volume." It's not that simple.

In addition to those anomoloies, some of which were pointed out on the thread I linked, there are also movies which are recorded at "Reference", but which don't sound like it. The standard we are used to hearing about is approximately 105db max for the speaker channels (although it may actually be 102 or 103, depending on interpretation) and 115db for the LFE channel. The Reference norm, therefore, is to have a nominal (not necessarily actual) average level of 85db, with 20db of dynamic peaks for the speaker channels, and 30db peaks for the LFE channels.

Many people equate that nominal 85db average with average dialogue levels. But, some movies deliberately mix at less than the nominal average of 85db, in order to have an even larger dynamic range. There was one notable example (I can't remember the movie right now, but maybe it was something like "Age of Ultron") that had average dialogue/noise floor levels of only 75db, so that when they hit 105db peaks, it would sound even more dramatic. The use of similar techniques probably varies quite a bit from movie-to-movie.

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…The first reason is that Audyssey is measuring the SPL of each speaker individually, based on a roughly 75db test tone. But, Audyssey is never measuring the sum of the speakers in a system. And, the sum of the speakers in a system (each playing at an individual level of 75db) will be louder than 75db. Most audio experts I have read on the subject, attribute about +1db for each additional speaker in a system. So, a 5.1 system, calibrated with a 75db test tone, would natively play louder than a 2.1 system, at a Reference volume of 0.0 MV, and so on…
I had a book with a table for how you added SPLs from different sources together from my old days working in health and safety but I can't find it. I did find this link to a calculator:

http://www.sengpielaudio.com/calculator-spl.htm

2 speakers playing at 75 dB sum to 77.5 dB (bit of rounding), 5 would sum to 82 dB, 6 (a 5.1 system) to 82.8 dB, 8 (a 7.1 system) to 84 dB, and 10 (a 5.21.4 system) to 85 dB. Your +1 dB per speaker is a reasonable guide for a 5.1 or 7.1 system but less so for other size systems. Adding a second speaker to get a 2 speaker stereo system actually increases the level by 2.5 dB but going from 5.1 to 5.1.4 with an Atmos setup (a 4 speaker increase from 6 to 10 speakers) would only generate a 2.2 dB increase. That's a big difference in the contribution to total SPL made by each additional speaker. The reason is that the second speaker is playing at the same level as the first and the summed volume is higher, the third speaker is playing at a level lower than the sum of the first 2, the fourth at a level lower than the sum of the first 3 and so on as you add speakers so the increase in total level from each additional speaker decreases as you keep adding speakers. You can see that with the 2.75 dB increase from 1 to 2 speakers, a 0.8 dB increase from 5 to 6 speakers, and a 1.2 dB increase from 6 to 8 speakers. Going to 10 speakers increases the level to 85 dB, a mere 1 dB increase over 8 speakers.

All of that, of course, is predicated on every speaker outputting 75 dB and in real life that is never the case. Some speakers will be outputting a higher level than others. Let's take a stereo situation for simplicity with both speakers outputting 75 dB each for a sum of 77.5 dB. If one speaker is 6 dB higher than another, the sum will be 1 dB higher than the level of the higher speaker. Let's say the first speaker is 75 dB and the second drops to 69 dB, the total output will be 76 dB so a drop of 6 dB in one speaker will drop the total level by 1.5 dB but if the first is 75 dB and the second increases to 81dB the total output will be 82 dB and we get an increase of 4.5 dB in summed output. I'm not even going to think about what might happen with a few increases and decreases in level from different speakers in a multichannel setup. A uniform change of x dB in every channel will produce a change of x dB in the summed level but if the change is not uniform in each channel it's anybody's guess what will happen, especially if some channels increase in level and some decrease.
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I had a book with a table for how you added SPLs from different sources together from my old days working in health and safety but I can't find it. I did find this link to a calculator:

http://www.sengpielaudio.com/calculator-spl.htm

2 speakers playing at 75 dB sum to 77.5 dB (bit of rounding), 5 would sum to 82 dB, 6 (a 5.1 system) to 82.8 dB, 8 (a 7.1 system) to 84 dB, and 10 (a 5.21.4 system) to 85 dB. Your +1 dB per speaker is a reasonable guide for a 5.1 or 7.1 system but less so for other size systems. Adding a second speaker to get a 2 speaker stereo system actually increases the level by 2.5 dB but going from 5.1 to 5.1.4 with an Atmos setup (a 4 speaker increase from 6 to 10 speakers) would only generate a 2.2 dB increase. That's a big difference in the contribution to total SPL made by each additional speaker. The reason is that the second speaker is playing at the same level as the first and the summed volume is higher, the third speaker is playing at a level lower than the sum of the first 2, the fourth at a level lower than the sum of the first 3 and so on as you add speakers so the increase in total level from each additional speaker decreases as you keep adding speakers. You can see that with the 2.75 dB increase from 1 to 2 speakers, a 0.8 dB increase from 5 to 6 speakers, and a 1.2 dB increase from 6 to 8 speakers. Going to 10 speakers increases the level to 85 dB, a mere 1 dB increase over 8 speakers.

All of that, of course, is predicated on every speaker outputting 75 dB and in real life that is never the case. Some speakers will be outputting a higher level than others. Let's take a stereo situation for simplicity with both speakers outputting 75 dB each for a sum of 77.5 dB. If one speaker is 6 dB higher than another, the sum will be 1 dB higher than the level of the higher speaker. Let's say the first speaker is 75 dB and the second drops to 69 dB, the total output will be 76 dB so a drop of 6 dB in one speaker will drop the total level by 1.5 dB but if the first is 75 dB and the second increases to 81dB the total output will be 82 dB and we get an increase of 4.5 dB in summed output. I'm not even going to think about what might happen with a few increases and decreases in level from different speakers in a multichannel setup. A uniform change of x dB in every channel will produce a change of x dB in the summed level but if the change is not uniform in each channel it's anybody's guess what will happen, especially if some channels increase in level and some decrease.

David,

Thanks, that's a very helpful post. I think that the roughly 1db increase did refer to going from 5 speakers to 7. But, I think you really highlight part of the reason why "Reference", as it applies to HT, can only be a general guideline, and not a numerical absolute.

It's a good point that not all of the speakers consistently play at the same volume in a 5.1 or 7.1 system. But, the times they are most likely to be playing at the same volume would be loud passages that might approach Reference peaks at 0.0 MV. I'm thinking of large-scale special effects, or even music crescendos, where the music suddenly swells from all of the speakers simultaneously.

As far as I have been able to tell, accurately predicting Reference (as some sort of absolute number) in a given HT system, is a pretty impossible task. If we are interested, we can try to measure the specific SPL in a specific room, but even with a really good calibrated mic, we won't be perfectly accurate.

The good news is that it really doesn't matter very much. Even if we were to actually listen at 0.0, which most of us would not wish to do in a typical home theater size room, whether our system were peaking at 103db, or 107db (excluding LFE, if it were possible to do that), probably wouldn't matter very much. If it were too loud, or not loud enough, we would simply adjust accordingly.

GUIDE TO SUBWOOFER CALIBRATION AND BASS PREFERENCES

* The Guide linked above is a comprehensive guide to Audio & HT systems, including:
Speaker placements & Room treatments; HT calibration & Room EQ; Room gain; Bass
Preferences; Subwoofer Buyer's Guide: Sealed/ported; ID subs; Subwoofer placement.

Last edited by mthomas47; 10-19-2016 at 04:02 PM.
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post #1439 of 7247 Old 10-19-2016, 04:18 PM
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David,

Thanks, that's a very helpful post. I think that the roughly 1db increase did refer to going from 5 speakers to 7. But, I think you really highlight part of the reason why "Reference", as it applies to HT, can only be a general guideline, and not a numerical absolute.

It's a good point that not all of the speakers consistently play at the same volume in a 5.1 or 7.1 system. But, the times they are most likely to be playing at the same volume would be loud passages that might approach Reference peaks at 0.0 MV. I'm thinking of large-scale special effects, or even music crescendos, where the music suddenly swells from all of the speakers simultaneously.

As far as I have been able to tell, accurately predicting Reference (as some sort of absolute number) in a given HT system, is a pretty impossible task. If we are interested, we can try to measure the specific SPL in a specific room, but even with a really good calibrated mic, we won't be perfectly accurate.

The good news is that it really doesn't matter very much. Even if we were to actually listen at 0.0, which most of us would not wish to do in a typical home theater size room, whether our system were peaking at 103db, or 107db (excluding LFE, if it were possible to do that), probably wouldn't matter very much. If it were too loud, or not loud enough, we would simply adjust accordingly.
Mike,

Re crescendos and special effects: I suspect you're right that all speakers more likely to be playing at the same level at those times but they probably won't be playing at the same level just prior to then so the increase in level of each speaker when the crescendo comes or the bomb goes bang isn't likely to be the same.

Prediction as you say is "a pretty impossible task". Measurement is much more accurate, a feature it shares with hindsight which is pretty much what your measurement is when you see the readout, even if it is only a millisecond or so of hindsight.

And you're spot on about reference level not mattering because we adjust our volume to suit ourselves. It's great for balancing levels during setup, it's a great standard to be used by software for features like dynamic EQ, but what we care about when we're sitting in front of the system listening to something is whether the volume is too loud, too soft, or just right. I don't bother seeing what the volume readout on the panel of my AVR is doing when I adjust volume unless I have something with an abominably low mastered volume (I have a couple of movies which fall into that category) and I have to keep raising and raising the volume. Normally my master volume setting is around -20 dB, give or take a couple of dB, and occasionally up to -10 dB but there are a couple of movies when I've either had to go to around -2 or 3 dB or raise the input level by 10 or 12 dB in order to get a level that delivered speech at a realistic and intelligible level and in real life speech is around 66 dB in level so a MV level above -10 dB in order to get something like normal speech volume levels from a soundtrack equates to a badly mastered soundtrack in my view.
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In addition to those anomoloies, some of which were pointed out on the thread I linked, there are also movies which are recorded at "Reference", but which don't sound like it. The standard we are used to hearing about is approximately 105db max for the speaker channels (although it may actually be 102 or 103, depending on interpretation) and 115db for the LFE channel. The Reference norm, therefore, is to have a nominal (not necessarily actual) average level of 85db, with 20db of dynamic peaks for the speaker channels, and 30db peaks for the LFE channels.

Many people equate that nominal 85db average with average dialogue levels. But, some movies deliberately mix at less than the nominal average of 85db, in order to have an even larger dynamic range. There was one notable example (I can't remember the movie right now, but maybe it was something like "Age of Ultron") that had average dialogue/noise floor levels of only 75db, so that when they hit 105db peaks, it would sound even more dramatic. The use of similar techniques probably varies quite a bit from movie-to-movie.
Normal voice levels in real life are actually around 65 dB. Reference level of 85 dB is set at -20 dB relative to peak amp output so the amps are capable of hitting the 105 dB peaks you mention without clipping. The lower you master the voices, the more effective a contrast the booms and bangs are going to make so it's easy to understand why an engineer might master voices at 75 dB or -30 dB below 0 mV rather than at 85 dB or -20 dB below 0 mV.

The problem is that we tend to listen at lower than reference level because peaks at 0 mV are just too loud for most of us in our rooms so we listen lower and if we set our master volume to -20 dB we're not setting it to 20 dB below 0 mv, we're probably setting it to closer to - 30 dB below 0 mV because the reference level our AVRs are calibrated to when we run setup is 75 dB, not the studio reference of 85 dB. The lower the engineer masters the voice, the lower the level they are going to be at our listening position and if we're turning the master volume down because the booms and bangs are too loud in a small space, then the voices are being turned down to and it's easy for them to end up being too low for clear intelligibility if the engineer masters them at a low level in order to emphasise the booms and bangs. There's actually a point to mastering voices so actual level ends up above 65 dB at the listening position because we tend to listen to voices in movies and the TV news and so on at above real life levels for clarity since we're further away from the (loud) speaker at home than we are from a (person) speaker in real life and the greater distance tends to ensure that reflected sounds have a bigger effect and can make it a little harder to understand dialogue so we want recorded voices to be louder than real voices.

Reference level has a meaning to the engineer, but where the engineer places things like voice level is an "artistic choice" to a degree and it depends a hell of a lot on what sort of a movie it is, whether it has a lot of booms and bangs or none at all, and what the overall dynamic range of the soundtrack is from softest to loudest passages.
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