That’s correct but we are talking about the shape of the curves, I.e. how much goes off at what frequency?'Everyone' agrees that bass (and high treble) balance goes off when levels are reduced.
That’s correct but we are talking about the shape of the curves, I.e. how much goes off at what frequency?'Everyone' agrees that bass (and high treble) balance goes off when levels are reduced.
Adjustable loudness, but does it follow automatically when you change the volume?I love the Yamaha variable loudness control. It's just well done. It can really transform a set of speakers into something else for awhile until the next setting comes down the pipe.
I has to be built-into the volume control circuit or the volume-control software. A basic loudness compensation circuit doesn't "know" the signal level or the acoustic loudness. It only knows the volume control setting. Variable loudness compensation helps you to adjust for that but it's still "imperfect". With software you can calibrate to the acoustic loudness, to some extent. (But you don't want to adjust dynamically to quiet passages, just for lower than expected listening levels.)
I found this. It's rather simple, just boosting the bass and there's no bypass switch. I think the old analog designs normally used a special volume control pot with an extra tap that could be switched-in. But I've never seen a pot like that available to hobbyists.
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)I made this a while ago.
Most recordings are mixed at average levels between 80 and 85dB (depending on the size of the mixing room and other factors)
I have 'normalized' 80 dB equal loudness contour and then you can see what 'compensation' you would need when you listen to different average levels.
Determining what average level you actually listen to is another matter.
I would say just apply EQ based on the right plot with your average SPL and the 80dB reference. When this sounds better to you and your speakers/headphones are correctly tuned this should work.
It is not by chance that my target curve is matching the 70dB line. I too listen at average levels (active listening) between 70 and 75dB average and well made recordings sound good to me on this target.
If 85 dB is reference I would guess most people are listening well below that, in which case a little sweetening of the EQ is probably warranted for most.This paper is about mastering and it recommends monitoring at 79 or 85 dB so that's a range where mastering engineer should be is monitoring. But a lot of home listening will be at lower levels... We aren't always listening at "realistic" sound levels.
Which is unfortunately quite wrong though (like on most such loudness circuits) as the treble should stay almost the same as shown from @solderdude.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)
Makes you wonder why Yamaha chose such an implementation, given that it seems quite a deliberate characteristic. It may be time to start playing with a few different variations in DSP that more closely follow the equal loudness curves. This time of year is always a good time to tinkerWhich is unfortunately quite wrong though (like on most such loudness circuits) as the treble should stay almost the same as shown from @solderdude.
Why would one NOT resort to them? Some might actually work for what you intended (making dialogue easier to hear without pumping up bass). It depends on how they are implemented in your AVR.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).
"treble hardly changes" , indeed much less then the bass, but still quite audible:Its not about the actual shape of the curves but the relative differences between different Phon level curves.
When you overlay the curves you will see the treble hardly changes.
People prefer bass and treble boost, certainly with lower levels and is why loudness control often is made this way and few complain about it.
Nevertheless, I was disappointed to find that it is a global modification.
As others have already pointed out, a test tone of -20dB should be modified differently from a tone at -10dB.
This does not seem to be the case.
The modification only depends on the master volume.
You are almost right, but there is some variation that should be handled. Let me give you an extreme example - others are less pronounced.This is exactly how it should be. The correction should be based on (preferably calibrated) gain and not on the signal itself. A dynamic loudness correction based on the signal itself does not make much sense.