Fletcher-Munson vs. Robinson-Dadson vs. ISO 226

Terry, I beg your pardon, but tuning flat would not make sense to me. As an acoustical engineer, I'm assuming that you of all people would calibrate your listening area with pink noise to some sort of equal loudness curve prior to mixing anything, correct? A flat room would sound horrible unless you were listening at extremely high levels, IMHO. I'm tuning to the curve which would approximate the older 80dB mean curve of Flectcher-Munson. As you can see (below), the Fletcher-Munson standard has only a 10dB rise on the bottom end, and does not include information for the bottom half-octave, whereas the ISO 226 curve has a full 39 dB sweep from 20hz to 500hz. This, to me, is an extremely dramatic change in tuning, and delivers a much more enjoyable response. Yes, I agree that high frequency roll-off at about 3dB per 1/3 octave beginning at around 12K seems to be appropriate for listening, at least in my experience.


ssabripo, I have both the Audio Control Industrial SA-3055A and an older Audio Control rack-style R-130; both are 1/3 octave RTAs. I prefer the SA-3055A though, as it has a setting for 3db/step increment (and has been recently calibrated), where the R-130 has only 2db and 4db increments, although either one does a pretty decent job, and both report similarly with regard to accuracy. It's just a bit easier to use the industrial unit.


I'm using 1/3 octave Audio Control 30 band mono EQs, frequency-matched to the analyzer, 24dB/octave slope.


I'm currently set to a close approximation of the ISO 226 curve for all-around listening and have found it to be quite enjoyable. I was simply wondering if any of you folks have done much experimenting of this sort.


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Quote:
Originally Posted by X2E /forum/post/15414069


Terry, I beg your pardon, but tuning flat would not make sense to me. As an acoustical engineer, I'm assuming that you of all people would calibrate your listening area with pink noise to some sort of equal loudness curve prior to mixing anything, correct? A flat room would sound horrible unless you were listening at extremely high levels, IMHO.

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No. The engineer who mixed the sound mixed it to reference level. If you are playing back at reference level, the sound will be the same if set flat. If you EQ for an equal loudness curve on top of this, it is simply wrong.


If lower volume than reference, then ideally, there should be psychoacoustic compensation. Like I said, this is done automatically in some receivers, where an EQ curve is tied to the volume control. But even old receivers and preamps have an on/off Fletcher-Munson type compensation. This is the "loudness" button.


Regards,

Terry

WOW I am laughing my you know what off. Is this just troll bait? If not, this is clearly a situation of "too much information". Rude you think? I think appropriate from a new poster who said

Quote:
Originally Posted by X2E /forum/post/15409744


I get the impression that most of the folks here don't even have a clue what they're really hearing

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and

Quote:
Originally Posted by X2E /forum/post/15409744


be prepared to be shamed

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These curves are meant to approximate non-linearity of human hearing, but they are information, not room tuning tools. A professional stage should be tuned flat so that the mixer can hear what really happens at differing frequencies at different volumes, which will be affected by his own hearing and the curves you noted.


If you build these curves into a recording system everything would be recorded lean. Then you would have to run your subwoofer even hotter than you do now to meet your tastes.


If you build these into your home system, you are playing back wrong and training your ear that what you are hearing is right. It is clear from your post you have not developed an ear for how a properly calibrated system should sound, rather you like exaggerated bass. These theories however do not explain the reason for your tastes.


Terry gave you the right answer right away, nicely I might add, and you told him he was wrong and threw an equipment list at him. You should learn how to use that stuff. There are many fools on this site, everyone knows who they are. But there are some professional mixers and people with very high end equipment and experience. To come into a place this large and expect that you are the smartest in the room just makes you the fool.

OK, so I was initially trolling...


and I initially exaggerated the response curve adjustments in question... I was bored, but this one grew larger than expected. Seems a few glasses of wine and a big spoon are all it takes to stir this forum into name calling, etc.


Sad.


Isn't this hobby (or profession) all about the enjoyment of the end user?


Bob Lee, glad to see you here, I see you're in Costa Mesa; I'm in Huntington Beach. I'll extend an invite to you to venture over west about 4 miles and hear for yourself what I'm doing here (though it's nothing like having a room curve that literally resembles ISO 226's equal sound curves, lmao!). I doubt you'll call me a fool, and may even be impressed; perhaps even lend to my credibility. PM me if you'd like to visit, you'd be welcome. But please do promise to report back to this forum on your impressions. (This would be imperative! lol)


Yes, I threw in some comments in my initial post intended to draw remarks. I got them.


However, I honestly expected to hear comments, topics or questions regarding A-weight, B-weight, C-weight, reverberation decay, waterfall charts, etc. prior to dismissing the notion of adjusting (slightly) the response curve of a listening room to compensate to a more recent understanding of human hearing in order to make things sound a bit more real (and also being called a fool by Harrypt- he's gained no points with me so far). If you all are listening to flatly-tuned rooms, I believe your next upgrade could be a good tuning, unless you're all following the flock that dictates you should have a flat curve. I dismissed that curve years ago... damn, the old A.M. car radio made Elton John sound better in the '70s than that curve would on your $50K system today... give me a break!


Harry, if you're listening, the smartest one in the room isn't always the one who calls names first, nor the one who shouts loudest, FYI.


To address the aforementioned point that some receivers can comp a response curve automatically, etc., I doubt that many of the folks around here using such products even know what these devices are doing to their response curves, and I'll bet that most of them boost lower frequencies beyond what they realize. They may well believe their curves are flat.... too much information? not enough? I guess it depends upon the day, the critic, no?


On top of that, I don't even have a receiver in my system, as most true audio enthusiasts would likely say the same, I'm sure. None of my equipment makes adjustments for itself, I prefer things to be this way.

Reference Level


In the final mix stages for film (music is pot luck), the room and the equipment is calibrated to reference level. "Reference" may not be your preferred playback level, but it is the baseline. In calibrating a space, we calibrate to, and at, reference level. Doing so provides a reasonable assurance we're hearing what the Sound Engineers/Directors heard during that mix. Since reference is used on both ends of the chain, we have (again) "reasonable" assurance our perceptual results match the perceptual results on the production side. This baseline level already accounts for our human sensitivity to sounds at various frequencies.


Now, once calibrated to the baseline, or reference, your preferred listening level can be set. If that level is higher, or lower, filters can be installed to compensate. For example, if you're a low level listener, a "loudness" contour can be installed to increase the SPL of the lower frequencies to compensate for our reduced sensitivity to those frequencies at lower SPLs.


Note: The A, B, C and D weighting in Sound Pressure measurement devices is effectively a compensator for the equal loudness curves.



Quote:
Originally Posted by Dennis Erskine /forum/post/15429606


Jonomega ... the best we can do is give you a second back.

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OP, as mentioned by Terry, Dennis, and others, the equal loudness curves are already accounted for by the recording engineers (except it is by their ears and not actual graph numbers). As an aside, some musical instruments are already adjusted to the loudness curves - the lowest pipes on the pipe organ are adjusted to loudness curves so that they subjectively as loud as the smaller pipes. Otherwise, you'd never be able to hear them.


Finally, just because we, perhaps, have "better" equal loudness curves now than before doesn't mean too much. The recording engineer's ear had been used before and is still being used now, regardless of the curves. It is perhaps not possible to figure out how much the recording engineer's ear departs from your own (due to lack of information). This information, however, would be needed for you to adjust your filters. Of course, this would differ with all program material and loudness levels...

Et Al...


It's been a pleasure stirring you up... yes, I've toyed with you all a bit, and, for the majority, your conceptions that everything must fall within your pre-conceived standards of "how things should be" (or how you've been told they should be) has been my greatest amusement. Yes, I'm accomplished in my own right, and have a considerable following. As I previously mentioned, some of you may have all the equipment you need, but not the ear to make IT make you happy.


It's been amazing to me how steadfastly some of you will hold on to ignorance.


My best advice to you is to start listening for yourselves, and forget what "the convention" tells you is correct. (Personally, I'd put my system up against 99.5% of them out there; However, I gave up my 1% ego a few years back when making a living became a clearer priority.)


To all of you "flat" listeners out there, loosen up and live a little... tune your system to what YOU prefer, and not what the "convention" tells you that you should enjoy... geesh!


Cheers!