Should you use Fletcher-Munson loudness compensation?

[EEE272]

The Yamaha variable loudness was well done.

The current crop of AS-xxx amplifiers are very disappointing

After being first disappointed that the correction of my Yamaha is global and now others also showed some bad examples. I wanted to save Yamaha's reputation.

The newer Yamaha Aventage receivers (RX-A3080) have really nice loudness correction curves that get very close to the expected behavior - and sound good...

I attached a screenshot. The top left is based on (https://www.merlijnvanveen.nl/en/calculators/59-equal-loudness), who provide the reference corrections based on the iso loudness curves for 70 dB - you can also calculate them yourself based on the iso curve data. You can see that there is quite a lot going on also for the treble and there is a dip between 1K and 8K.
Top on the right is the result of YPAO Volume taken directly from the preout.
It matches up really nicely down to 100Hz. Above 12K, the iso curves should apparently not be followed. Thus Yamaha tapers them out at the last valid value.

In terms of comparison to the target curve, we first off see that the lower end is not raised correctly - it should be more linear. This is probably done because of the fear that it might strain the subwoofer or that, if used at night, you don't want to wake up everyone due to low frequencies wobbling through the house (someone even mentioned this a few posts above). The second deviation from the target curve is that 1K and 8K seem to be the points where the curves should meet. The 1K is close enough, 8K goes up a bit too early (ballpark of 0-2dB depending on how low your listening level is).

Nevertheless, these two mistakes can be easily corrected by using the PEQ of YPAO. I, on purpose, only used a single PEQ for the low end (I could use more here because the bass is already linearized by a MiniDSP, so all bands are available). At the top end it is not too crucial, as mentioned, the curves are pretty close. Nevertheless, one PEQ with small amplitude can produce a better linearity (the curves are almost linear between 8K-12K), and we can ensure the meeting point at 8K. The end points after adjustment with the PEQ end up nicely at their target level and the curves are very close. The result is below. Pretty nice actually!

When I listen to a movie, it is enough to choose the volume, then adjust the PEQ (it is simple - they can be kept in the same location, only gain (2 up) and Q (1 down) change per 5 dB).

It took me some time to figure out that the reference is 70dB and initially tried to match 85dB. I thought that it would be too low but the more I pondered about it, the more I feel like it might be a good tradeoff. For "hotter" mixes, it kicks in a bit late but then the compensation is also a bit stronger, which seems to work out well. For Netflix with its -27LUFS (and 79 reference) it seems to be a nice fit.

I am new on this forum but learned a lot in recent days - especially about mixing, which really helped me grasp what was going on.
Probably, what I am about to say is still only half correct...
But anyway a big thanks for all the input that I got in the last days.


If I understood correctly, when people master audio, they start by choosing the reference. I always thought that you target a different dB value, but it seems that most dial down their amp. This means if you mix for -20=79d, you dial down the amp to -6. Your software can then produce sounds at 0dB that are sent to the amp, translate to -6dB, and on a calibrated system, it produces 99 dB SPL.
Now comes the interesting part - the knowledge that the amp was set to -6 is completely lost in the end. Thus, if you now run the result on a calibrated system, the sound will actually be 6dB too hot - the actual reference setting would be -6dB.

You might not even notice the different reference level easily because Netflix targets -27LUFS with a reference of -20=79. LUFS measure loudness over time. Playing pink noise at -20dBA seem to lead to -21 LUFS over time. Following Netflix, you try to end up with a target of -27 LUFS. That is -26dBA for pink noise. Thus, on a calibrated system that leads to an increase of 6dB, the pink noise is again around -20dB, which is not far off of what you would see in a standard 85 cinema mix.

Let's come to our example for the loudness curve. You have mixed for 70dB. For a calibrated receiver, it means that loudness should kick in at the setting of exactly -15dB (for the reasons outlined above, on a calibrated system, the mix is played with 15dB too much).
Above the -15dB setting, the Yamaha does not apply loudness, below YPAO volume is activated (the flat line is -15dB).

What about souces that are mixed higher? You can use the "input trim" to shift the moment that YPAO volume becomes active upwards.
You don't have to go 15 dB to get a good correction - with +6dB, you are very close to the Netflix case. But even just leaving it as is without input trim does a great job.

I definitely enjoy listening with the compensation because I do admit that I have a tendency to listen a at lower volumes. Hope this rant helps a bit!

 

[levimax]

After being first disappointed that the correction of my Yamaha and now others also showed some bad examples. I wanted to save Yamaha's reputation.

The newer Yamaha Aventage receivers (RX-A3080) have really nice loudness correction curves that get very close to the expected behavior - and sound good...

I attached a screenshot. The top left is based on (https://www.merlijnvanveen.nl/en/calculators/59-equal-loudness), who provide the reference corrections based on the iso loudness curves for 70 dB - you can also calculate them yourself based on the iso curve data. You can see that there is quite a lot going on also for the treble and there is a dip between 1K and 8K.
Top on the right is the result of YPAO Volume taken directly from the preout.
It matches up really nicely down to 100Hz. Above 12K, the iso curves should apparently not be followed. Thus Yamaha tapers them out at the last valid value.

In terms of comparison to the target curve, we first off see that the lower end is not raised correctly - it should be more linear. This is probably done because of the fear that it might strain the subwoofer or that, if used at night, you don't want to wake up everyone due to low frequencies wobbling through the house (someone even mentioned this a few posts above). The second deviation from the target curve is that 1K and 8K seem to be the points where the curves should meet. The 1K is close enough, 8K goes up a bit too early (ballpark of 0-2dB depending on how low your listening level is).

Nevertheless, these two mistakes can be easily corrected by using the PEQ of YPAO. I, on purpose, only used a single PEQ for the low end (I could use more here because the bass is already linearized by a MiniDSP, so all bands are available). At the top end it is not too crucial, as mentioned, the curves are pretty close. Nevertheless, one PEQ with small amplitude can produce a better linearity (the curves are almost linear between 8K-12K), and we can ensure the meeting point at 8K. The end points after adjustment with the PEQ end up nicely at their target level and the curves are very close. The result is below. Pretty nice actually!

When I listen to a movie, it is enough to choose the volume, then adjust the PEQ (it is simple - they can be kept in the same location, only gain (2 up) and Q (1 down) change per 5 dB).

It took me some time to figure out that the reference is 70dB and initially tried to match 85dB. I thought that it would be too low but the more I pondered about it, the more I feel like it might be a good tradeoff. For "hotter" mixes, it kicks in a bit late but then the compensation is also a bit stronger, which seems to work out well. For Netflix with its -27LUFS (and 79 reference) it seems to be a nice fit.

I am new on this forum but learned a lot in recent days - especially about mixing, which really helped me grasp what was going on.
Probably, what I am about to say is still only half correct...
But anyway a big thanks for all the input that I got in the last days.


If I understood correctly, when people master audio, they start by choosing the reference. I always thought that you target a different dB value, but it seems that most dial down their amp. This means if you mix for -20=79d, you dial down the amp to -6. Your software can then produce sounds at 0dB that are sent to the amp, translate to -6dB, and on a calibrated system, it produces 99 dB SPL.
Now comes the interesting part - the knowledge that the amp was set to -6 is completely lost in the end. Thus, if you now run the result on a calibrated system, the sound will actually be 6dB too hot - the actual reference setting would be -6dB.

You might not even notice the different reference level easily because Netflix targets -27LUFS with a reference of -20=79. LUFS measure loudness over time. Playing pink noise at -20dBA seem to lead to -21 LUFS over time. Following Netflix, you try to end up with a target of -27 LUFS. That is -26dBA for pink noise. Thus, on a calibrated system that leads to an increase of 6dB, the pink noise is again around -20dB, which is not far off of what you would see in a standard 85 cinema mix.

Let's come to our example for the loudness curve. You have mixed for 70dB. For a calibrated receiver, it means that loudness should kick in at the setting of exactly -15dB (for the reasons outlined above, on a calibrated system, the mix is played with 15dB too much).
Above the -15dB setting, the Yamaha does not apply loudness, below YPAO volume is activated (the flat line is -15dB).

What about souces that are mixed higher? You can use the "input trim" to shift the moment that YPAO volume becomes active upwards.
You don't have to go 15 dB to get a good correction - with +6dB, you are very close to the Netflix case. But even just leaving it as is without input trim does a great job.

I definitely enjoy listening with the compensation because I do admit that I have a tendency to listen a at lower volumes. Hope this rant helps a bit!

I just turn up the bass until it sounds good when listening at low levels

 

[symphara]

I’m not sure if you’re joking, but it seems obvious your wife is turning this feature on! She’s amused because you don’t always notice.

I’m not joking at all, but what you’re saying is grounds for divorce!

 

[solderdude]

70dB average on most recorded music is what most people listen to for longer periods = a comfortable level.
60dB average is a comfortable background level (no one listens at that level)
Most music is mixed at levels of around 80-85 dB average which is comfortable loud one only uses occasionally when one really likes a song.
90-95dB average is already loud and after a minute you get the urge to dial back but no one dials down the bass at these levels so no need to compensate above 85dB.
So in reality one only has to correct for 70dB and 60dB average levels and maybe for 50dB when music is playing at a very low background level and you want to conduct a normal conversation at a normal level.
Pointless to do this for 40dB SPL as this is already near silence let alone for lower levels..

Note: peak levels can be between 5 and 20dB higher than the listed average levels above depending on the recording.

 

[EEE272]

70dB average on most recorded music = a comfortable background level.
60dB average is soft background level (no one listens at that level)
Most music is mixed at levels of around 80-85 dB average which is comfortable loud one only uses occasionally when one really likes a song.
90-95dB average is already loud and after a minute you get the urge to dial back but no one dials down the bass at these levels.
So in reality one only has to correct for 70dB and 60dB average levels.
Pointless to do this for 40dB SPL as this is already near silence.

Note: peak levels can be between 5 and 20dB higher than the listed average levels above depending on the recording.

The curves do not change drastically from 70 reference to 80 reference when not too far off. That is why the input trim shift probably also works well.
I still like that the curves are really reasonable and relatively detailed.

 

[solderdude]

Indeed the change is just a few dB for the lows and less than 1dB for upper treble (above 10kHz)
Just saying that there is no real need to compensate above 85dB average SPL nor is it very useful to compensate more below 60dB SPL or so
The 'range' needed for loudness control thus is rather small.

 

[symphara]

Stimulated by this thread, I just played for about 15 minutes with Dynamic EQ on my 8500 (I believe it applies exactly the type of curve mentioned here).

Way too much bass at lower volumes. I tried different reference points while listening to jazz and it wasn’t right.

Also, one of the immediate effects of engaging Audyssey (as opposed to Direct) on this system I was listening to (Triangle Speakers driven by an Electrocompaniet in HT bypass driven by said Denon 8500) was the shrinkage of the sound stage to a point in the middle of the speakers. Otherwise the sound stage is very expansive.

 

[EEE272]

I just turn up the bass until it sounds good when listening at low levels

For music, this is not a bad solution. For movies, unfortunately, the bass/ treble only apply to the fronts, which would make things very unbalanced.

 

[symphara]

I’m not sure if you’re joking, but it seems obvious your wife is turning this feature on! She’s amused because you don’t always notice.

I re-did the whole setup for the 8500 this evening, from factory reset. I tried using the Audyssey iPad app but it always ran into communications problems with the receiver so I gave up eventually and reverted to the normal setup.

It asks, during the setup, whether you want Dynamic EQ (I chose Yes) and Dynamic Volume (I chose No).

After completed, I switched to my nVidia Shield to try a Dolby Atmos demo. Surprise! Dynamic EQ was set to No and Dynamic Volume was set to Medium.

This has been my experience with all three Sound United receivers. They just randomly turn on and off these features. Mine do not honor the setup configuration, nor do they remember the last setting.

I wish I were joking.

 

[dshreter]

I re-did the whole setup for the 8500 this evening, from factory reset. I tried using the Audyssey iPad app but it always ran into communications problems with the receiver so I gave up eventually and reverted to the normal setup.

It asks, during the setup, whether you want Dynamic EQ (I chose Yes) and Dynamic Volume (I chose No).

After completed, I switched to my nVidia Shield to try a Dolby Atmos demo. Surprise! Dynamic EQ was set to No and Dynamic Volume was set to Medium.

This has been my experience with all three Sound United receivers. They just randomly turn on and off these features. Mine do not honor the setup configuration, nor do they remember the last setting.

I wish I were joking.

That's super weird, but I'm glad you can replace the receiver instead of your wife. Good wives are harder to come by than good surround sound processors, which says a lot.

 

[symphara]

That's super weird, but I'm glad you can replace the receiver instead of your wife. Good wives are harder to come by than good surround sound processors, which says a lot.

I just bought the damn thing, and it cost a pretty penny The receiver, not the wife! But given that my Marantz and my 4700 do the same thing, I feel it’s a Sound United “feature”.

 

[ZolaIII]

Great even AVR's can't include DSP into propetry Dolby bit streams (nor DSD), so it turns it off (EQ) and to the default "dynamic volume".

 

[Sal1950]

This has been my experience with all three Sound United receivers. They just randomly turn on and off these features. Mine do not honor the setup configuration, nor do they remember the last setting.

I wish I were joking.

That's strange, neither my Marantz 7701 or 7703 exhibit any instability in it's setting?
I must add over the many years I've been involved in forums dealing with this gear, yours is the first time I can remember any mention of this??

My main beef (and many others) with Audyssey DEQ is their insistence that front to rear balance needs to be changed with DEQ. When using DEQ rear channel levels are increased for a reason I've never understood or agreed with.
Otherwise it's implementation of the F-M curve is pretty well done for low level listening.
I do wish there was a button to engage-disengage on the remote like there is on the front panel but that's a minor quibble.

 

[dasdoing]

on a sidenote: Fletcher-Munson is terribly outdated and actualy sounds bad for loudness compensation.
we have Iso-226 for 19 years now and people still rely to Fletcher-Munson from 1933?
[Dasdoing out]

 

[Sal1950]

on a sidenote: Fletcher-Munson is terribly outdated and actualy sounds bad for loudness compensation.
we have Iso-226 for 19 years now and people still rely to Fletcher-Munson from 1933?
[Dasdoing out]

I think it's more the F-M curve name, like frigidare is stuck in our heads after all these years.
I have no idea if DEQ follows F-M, Iso-226 (of which I was not aware) or any other comp example.
It was just the first thing that came to my head.

 

[symphara]

That's strange, neither my Marantz 7701 or 7703 exhibit any instability in it's setting?
I must add over the many years I've been involved in forums dealing with this gear, yours is the first time I can remember any mention of this??

My main beef (and many others) with Audyssey DEQ is their insistence that front to rear balance needs to be changed with DEQ. When using DEQ rear channel levels are increased for a reason I've never understood or agreed with.
Otherwise it's implementation of the F-M curve is pretty well done for low level listening.
I do wish there was a button to engage-disengage on the remote like there is on the front panel but that's a minor quibble.

I have nothing useful to add. This has been my experience, and it’s been mystifying. I agree with you on DEQ and the increased levels of rears, it upsets me too, particularly if the volume is low. Otherwise the curve is good - for movies. For music, I generally find Audyssey a big no-no with the exception I mentioned.

 

[Sal1950]

For music, I generally find Audyssey a big no-no with the exception I mentioned.

You need to get the app running correctly on your ipad and limit its FR to under 500hz.
I'll give you this hint, before you attempt to run the app, completely reboot the ipad to clear it's memory and don't run any thing else while doing the wizard. If still no joy you need something with more memory.

 

[Andysu]

I re-did the whole setup for the 8500 this evening, from factory reset. I tried using the Audyssey iPad app but it always ran into communications problems with the receiver so I gave up eventually and reverted to the normal setup.

It asks, during the setup, whether you want Dynamic EQ (I chose Yes) and Dynamic Volume (I chose No).

After completed, I switched to my nVidia Shield to try a Dolby Atmos demo. Surprise! Dynamic EQ was set to No and Dynamic Volume was set to Medium.

This has been my experience with all three Sound United receivers. They just randomly turn on and off these features. Mine do not honor the setup configuration, nor do they remember the last setting.

I wish I were joking.

sound united are load of rubbish. I keep the dynamic eq/volume switched off, well since I don't use that rubbish audyessey I can't use the dynamic eq. Besides the Behringer DCX2496 have dynamic eq but I rarely now use it anymore. I tinkered with it years ago with troublesome deafening movies, like, 'jurassic park 3' with a super-dyno eating some guy running around with gun then scene goes quiet for 1sec then a guy gets punched and then some soft dialog. Movie mixes are rubbish, they are just as fake as. grrr, so I messed with dynamic eq to make the silly unnecessary deafening dinosaurs sound quieter and make the softer sounds audible. The DCX has LCR input on A B C and used as two-way crossover LCR. Or you can use lots of DCX.

 

[Andysu]

Changing the EQ curve on thee HF horns for a higher elevation. Test for hours other night listening to a dialog scene from Poltergeist chapter 13 with mosquitoes buzzing around the common LCR.

 

[symphara]

You need to get the app running correctly on your ipad and limit its FR to under 500hz.
I'll give you this hint, before you attempt to run the app, completely reboot the ipad to clear it's memory and don't run any thing else while doing the wizard. If still no joy you need something with more memory.

I have a brand new 11" iPad Pro. It can run Divinity: Original Sin 2 without a hitch. The app is supposed to run on phones!

I'm considering buying an Audyssey:X licence.