Should you use Fletcher-Munson loudness compensation?

[RayDunzl]

I don't use loudness compensation.

The curves represent how we perceive, not what we should adjust, in my opinion.

I listen (if listening attentively) in the 80 to 100dB area (average and peak) where the FM curves are mostly flat, anyway.

If listening casually and at lower levels, I'm not bothered.

 

[EEE272]

I don't use loudness compensation.

The curves represent how we perceive, not what we should adjust, in my opinion.

I listen (if listening attentively) in the 80 to 100dB area (average and peak) where the FM curves are mostly flat, anyway.

If listening casually and at lower levels, I'm not bothered.

Then indeed, you don't need loudness compensation. But you really listen at 80dB A weighted? So, around -5dB on your receiver, assuming it iscalibrated? I am not criticizing, just curious because I really don't enjoy listening that loud at home for longer periods.

In my case, even when listening attentively, I listen at a lower volume. Typically, 70dBA with peaks at 85dBA. At this level, the tonal composition does sound slightly off.
Here, loudness compensation does magic - it sounds fuller and matches much more what I perceive when (exceptionally) cranking up the stereo. Also in movies, the nice rumbling you hear when there are explosions is not the same and I would miss it otherwise.

 

[abdo123]

Then indeed, you don't need loudness compensation. But you really listen at 80dB A weighted? So, around -5dB on your receiver, assuming it iscalibrated? I am not criticizing, just curious because I really don't enjoy listening that loud at home for longer periods.

In my case, even when listening attentively, I listen at a lower volume. Typically, 70dBA with peaks at 85dBA. At this level, the tonal composition does sound slightly off.
Here, loudness compensation does magic - it sounds fuller and matches much more what I perceive when (exceptionally) cranking up the stereo. Also in movies, the nice rumbling you hear when there are explosions is not the same and I would miss it otherwise.

No body calibrates their system with an A-weighted microphone, it’s usually C-weighted.

 

[EEE272]

No body calibrates their system with an A-weighted microphone, it’s usually C-weighted.

Yes, it is C-weighted when calibrating, but a cinema mix is then done with a target of around -27 dB for dialog. Dialog is around the flat part of the A weighted curve. Of course, this is approximate, as there are home entertainment mixes etc. But if you take an SPL meter to the movies, it usually is in that ballpark.

Edit: and just to clarify, he said the curves would be rather flat in his case, which would imply a -5dB receiver setting and then the dialog and A weighted is easily in this area of 85dB. For me, that is too loud but I might enjoy it occasionally and would understand that others do so more often.

 

[RayDunzl]

But you really listen at 80dB A weighted?

No, unweighted 80 or 85dB (averaged over time) to 100 or 105dB SPL (peak), with flat equalization.

But not all the time. Generally reserved for when Audio Buddy comes over and we want to really listen to something special.

We are both experienced with live instrumentation, acoustic and amplified, so it isn't that much of a stretch.

So, around -5dB on your receiver,

No receiver in this room.

 

[EEE272]

No, unweighted 80 or 85dB (averaged over time) to 100 or 105dB SPL (peak), with flat equalization.

But not all the time. Generally reserved for when Audio Buddy comes over and we want to really listen to something special.

We are both experienced with live instrumentation, acoustic and amplified, so it isn't that much of a stretch.




No receiver in this room.

Thanks for your answer. That seems coherent with what I thought and it is indeed much louder than my usual levels.
I typically end up with peaks at 85 dBC but for relaxed listening, I stick rather to 75-80 dBC.
That is also why I really benefit from some loudness compensation.

 

[MKreroo]

View attachment 176066I know many are familiar with the Fletcher-Munson or equal loudness curves. In a nutshell:

“The Fletcher Munson Curve contains a set of graphs that show that when you listen to music at a lower volume, mid-range frequencies will be sound more prominent, whereas high and low frequencies will be somewhat suppressed.

However, when the volume is increased, the reverse happens – high and low frequencies become more pronounced while the mid-range frequencies fade into the background.

In other words, the Fletcher Munson Curve demonstrates the average sensitivity of a human ear to audio signals of different frequencies at varying sound levels.”

I have a few questions about what this implies in practice.

Should you compensate for this in your own listening? I’m aware in psychoacoustics the brain naturally compensates for many things, so does fully adjusting for equal loudness compensation at low levels sound wrong or is it more similar to the intended mix? And in reference to music, what level is considered reference that you would compensate in relation to?

Given I tend to listen to music at lower volumes I am a bit lost on what to use as a target response curve for EQing my speakers. I could just do what sounds “best” but a little extra bass always sounds good for a little while so I don’t exactly trust my ears to get it right.

I'm confused by this:
"However, when the volume is increased, the reverse happens – high and low frequencies become more pronounced while the mid-range frequencies fade into the background."
Judging by the fact that ISO-226 (red), superseded the Fletcher-Munson Curver, and what the curve shows, isn't human hearing for both low and high remain much of the same across volume level, while only the mid raise slightly, but still below both low and high? (the bump around 1k remain across all volume level)
so how does the mid range fade into the background when it seems to still be the mos sensitive part?

 

[solderdude]

What @dshreter is saying is correct.
He is saying that at lower volume we do not hear bass as loud (and upper treble) and that when you increase the volume (all without Contour on) we will perceive more bass (and a smidgeon more upper treble)

 

[DanielT]

It is very easy to make sure that this is the case. Turn down the volume to the lowest audible volume. Listen with speakers. How much bass and treble do you hear then? Then turn up the volume, listen and compare.

Loudness that adjusts automatically with the volume. I'll fix that. Somehow. I think that (for my own part) it will do a lot for the sound quality. I often listen with different volume levels. Exciting!

 

[MKreroo]

What @dshreter is saying is correct.
He is saying that at lower volume we do not hear bass as loud (and upper treble) and that when you increase the volume (all without Contour on) we will perceive more bass (and a smidgeon more upper treble)

oh so as in at higher volume, relative to low/high, the mid fades (not perceived as loud as before), not that it just disappear. thought fade as in just fade into fog and gone

 

[restorer-john]

I love the Yamaha variable loudness control. It's just well done.

The Yamaha variable loudness was well done.

The current crop of AS-xxx amplifiers are very disappointing in the variable loudness curves compared to their old ones. Basically, they've cut down the number of components in the filters to reduce costs.

Looking at my Yamaha A-S301 loudness control, as you increase the loudness (from flat) the output level decreases but the bass and treble is boosted (relatively)

This is a Yamaha AS-300 loudness, which should be identical. Equal steps back with a fixed volume pot position. Y axis in Volts over 8R. As you can see the control becomes useless near the last three sweeps actually losing treble and mids. It's a mess compared to how they once implemented their famous variable loudness.

Here's much better 3 position variable loudness on a 1980s Akai preamplifier:

 

[DanielT]

The Yamaha variable loudness was well done.

The current crop of AS-xxx amplifiers are very disappointing in the variable loudness curves compared to their old ones. Basically, they've cut down the number of components in the filters to reduce costs.


This is a Yamaha AS-300 loudness, which should be identical. Equal steps back with a fixed volume pot position. Y axis in Volts over 8R. As you can see the control becomes useless near the last three sweeps actually losing treble and mids.

View attachment 178431

Ok but are there amplifiers with sensible variable to volume adjusted automatic loudness? Screwed in according to Fletcher-Munson loudness compensation?

Or do you have to fix that yourself with EQ settings (somehow) in the digital world?

 

[symphara]

Denon Audyssey Dynamic EQ seems to work as intended. I.e. When listening at low volumes it boosts the bass so that the subjectively perceived balance between bass and other frequencies is closer to what would be experienced at higher listening levels. (Sometimes the boost is too much, but the reference level offset is helpful in adjusting this).

However, Dynamic EQ isn't necessarily always what you want. For example, if you are reducing volume to avoid disturbing others in the house, then the last thing you want to do is increase the ratio of bass. To prevent the bass from reaching other rooms you would have to decrease the volume even further, making mid frequency dialogue difficult to hear properly (without resorting to dynamic range compression/ dialogue enhancement/ midnight mode etc).

For the second part, Audyssey provides Dynamic Volume (which is a dynamic range compressor that also kills some bass) and also Audyssey LFC which is specifically designed to kill the bass.

I personally find these two features too damaging to the sound, to the amusement of my wife I can tell immediately even if Dynamic Volume is set to "Light" (which inexplicably all my Denon and Marantz receivers randomly do - I have an 8500, a 4700 and a 7010, they all sometimes enable Dynamic Volume by themselves, to my despair).

There's a lifelessness to the sound, more pronounced as the setting goes from Light to Heavy. Setting Dynamic Volume to "Heavy" and LFC to "on" makes for terrible output but I guess it could be useful in an apartment with very thin walls and twitchy, crazed neighbours.

Dynamic EQ however works well for movies.

For music, I find Audyssey a mixed bag. It generally muddies the sound, but I did get good results with it in my apartment, with a Denon 4700 and Amphion Helium speakers.

 

[restorer-john]

Ok but are there amplifiers with sensible variable to volume adjusted automatic loudness? Screwed in according to Fletcher-Munson loudness compensation?

That's what the amplifier manufacturers tried to do, but the level of each individual recording and the efficiency of the attached speakers could not be predicted.

So, they tended to 'add a bit extra' and loudness curves became ridiculous.

 

[restorer-john]

Amphion Helium speakers

With a name like that, we already know what they sound like.

 

[solderdude]

oh so as in at higher volume, relative to low/high, the mid fades (not perceived as loud as before), not that it just disappear. thought fade as in just fade into fog and gone

When the volume (SPL) is lower the bass (and upper treble) 'fade' while mids are still audible.
The higher the SPL the sound gets 'fuller' as bass becomes relatively louder.
So in essence the bass fades the lower the SPL. The mids do not.

 

[ZolaIII]

@restorer-john speakers changed (more rigid cones and more stressed) and so did curve, Yamaha just adopted it to how it should be with most newer speakers.

 

[symphara]

With a name like that, we already know what they sound like.

You'd be surprised

 

[DanielT]

That's what the amplifier manufacturers tried to do, but the level of each individual recording and the efficiency of the attached speakers could not be predicted.

So, they tended to 'add a bit extra' and loudness curves became ridiculous.

The use of loudness. It partly depends on the type of music I listen to and the mood you are I am in and of course the level of the volume matters, (or that is what matters).Sometimes I push in loudness, sometimes not. Then these bass-poor old hard rock recordings that need an extra bass push ... and so on and so forth.

When I think about it, if you can fiddle with it, set the EQ for each individual song. Then when song X is played, the EQ setting is set automatically. Sure, there are a lot of gains with it, but hell what a lot of workshop to fix to that for each song.
..plus this with changes at different volumes and ... breath....A lot of steering with the EQ knobs it will be,..as Yoda said. Fun.

 

[dshreter]

I personally find these two features too damaging to the sound, to the amusement of my wife I can tell immediately even if Dynamic Volume is set to "Light" (which inexplicably all my Denon and Marantz receivers randomly do - I have an 8500, a 4700 and a 7010, they all sometimes enable Dynamic Volume by themselves, to my despair).

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.