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Quote:

TO heat the pot some, those who have Tinnitus, how do we know they have it? What frequencies? You have to rely on the person saying...my tinnitus is this or these pitches and sometimes it happens in one ear loudly and then quietens down. How does science and research measure ones actual spectrum in frequency of tinnitus?  Tinnitus is subtle and most have it...but very very subtle. Those who say they dont (and have 0dB perception) are not attuned to its presence. It is there if you have been engineering as long as I have. I certainly don't have zero dB perception. Even 3K must be 32dB for me to hear it. I never knew of a case of someone placing a microphone to ones ear and measuring or recording the tinnitus because it is a nerve function and not one of passive vibrations...(although ultrasonics will affect its perception)

If we can be straight about one thing on this thread, let's be straight about this: tinnitus is a hearing disorder.

Let's call it a perceptual disorder where the subject hears tones or ringing despite the absence of any stimulus.  Tinnitus (the perceptual phenomena) sometimes is experienced in conjunction with an objectively measurable phenomena.  In other words, sometimes it is measurable with microphones in the ears.  

Measurable sounds produced by the hearing system when stimuli are not present are called Spontaneous Otoacoustic Emissions (SOAEs).  About 50% of people with normal hearing (no tinnitus) have SOAEs.  SOAEs are not stable and come and go; however, the  intra-subject frequencies of SOAEs are stable.  Healthy ears which exibit SOAEs have no difficulty hearing stimuli in the same frequency bands  as the emitted sounds.    

Subjects who report tinnitus often exhibit SOAEs measured higher than 20 dB spl inside the ear.  These same subjects have difficulty hearing stimuli in the same frequency bands as the emitted sounds.

Please see: Zwicker and Fastl  Psychoacoustics: Facts and Models ISSSN 0720-678X, Chapter 3 for details.

[natpub]

bobkatz wrote on Sun, 28 November 2004 19:05

...Scientists have already quantified the ear's memory...

Bob,  I believe you meant to say the "brain's" memory (not the ear); as the ear, in general, has no memory, per se. (/teasing!)

I think you are referring to the brain's areas of sonic memory, residing principally in the temporal lobe area, though memory of any single sense can involve all areas of the brain and other combinations of senses. The reason they call the temporal lobe the "center of hearing" only indicates a primary area of activity, not exclusive.

Further, other bodily tissue itself can "remember" certain things as well, compounding matters even more. Parts of memories may actually be stored elsewhere in the body besides the brain.

As far as "quantifying" memory duration/accuracy goes, I don't need to have read the particular research you may be citing to know that someone is vastly oversimpfying and drawing hasty/distorted conclusions. I would advise scepticism re: any conclusions one may try to make here as to the veracity of such claims.

Some things to consider in these audio comparrisons are a few research fundamentals, including:

1. ZEIGARNIK EFFECT - n :  The psychological tendency to remember an uncompleted task rather than a completed one." [While this may not seem immediately applicable to your A/B/X tests, if you think on it, you will see why it applies]

2. HAWTHORNE EFFECT  - n : "An individual's behavior being altered because they know they are being studied."

And the more recent and theoretical:

3. OBSERVER EFFECT (Quantum mechanics)-  Behavior of the very smallest objects (like electrons, for example) is very unlike the behavior of everyday things like baseballs. When we throw a baseball at a wall, we can predict where it will be during its flight, where it will hit the wall, how it will bounce, and what it will do afterward.

When we fire an electron at a plate with two closely spaced slits in it, and detect the electron on a screen behind these slits, the behavior of the electron is the same as that of a wave in that it can actually go though both holes at once. This may seem odd, but its true. If we repeat this experiment lots of times with lots of electrons, we see that some positions on the screen will have been hit by many electrons and some will have been hit by none. The observed "interference pattern" for these electrons is evidence of their dual wave-particle nature, and is well described by thinking of each electron as a superposition of two "states", one that goes through one slit, one that goes through the other.

To add to this already mysterious behavior, this interference will only happen if both possible paths that the electron can take are not distinguishable. In other words, if we could somehow tell which slit the electron went through each time, we would no longer get the interference. The act of making a measurement of the electrons path fundamentally changes the outcome of the experiment.


Cheers,

[Level]

"It is the the electromotive and correlation to the electro-motives, that give certain stimulation and simulation to each one, based on their chemical makeup, and actual attitudes and acceptance, that are beyond our present control..but observed by the indivigual. It can vary by the moment in a said indivigual as well"

My Quote.

[natpub]

Level wrote on Wed, 01 December 2004 01:14

"It is the the electromotive and correlation to the electro-motives, that give certain stimulation and simulation to each one, based on their chemical makeup, and actual attitudes and acceptance, that are beyond our present control..but observed by the indivigual. It can vary by the moment in a said indivigual as well" My Quote.

LOL, brilliant--now, back to your calibration with you!!  

[Level]

Shit, it changes by the moon phase, how dare you make me work so hard....

[natpub]

I think I spent too much time trying to verify those Timothy Leary experimental results  

[Level]

 

[ammitsboel]

bobkatz wrote on Sat, 27 November 2004 15:29

heinz wrote on Fri, 26 November 2004 23:00 Greetings, Some time back there were statements made in a thread here to the effect that, when one performs A/B comparisons between two similar pieces of audio, that there is a limit to the time that can be spent "switching" between sources before the ear "forgets" and no longer can accurately compare. I've searched in vain and would like to know again... was it three seconds? Thanks and best regards Heinz Jim Johnston is the expert on this. Unfortunately he does not participate in this forum. Three seconds is MUCH too long. Something like less than 250 ms if I recall correctly or the brain forgets minute details. And there must not be a gap, very tiny if at all, no more than a millisecond or two, or the brain gets completely fogged. I wish I had a perfect database, somewhere in all my emails I have Jim's exact answer.

I think the question is if very quick A/B testing mean something at all.
What do you hear as differences when doing this? i hear mostly ballance differences or other things that lies in the "top surface" of the song.

If I'm doing a real A/B test I play a whole number or at least whole phrases of it. And by doing that i can catch far more important sound differences in A and B than if i did a quick A/B test.
Quick A/B testing is useless IMO.

Best Regards

[Nika Aldrich]

It depends on what you're testing.

Nika

[bobkatz]

ammitsboel wrote on Wed, 01 December 2004 09:40

If I'm doing a real A/B test I play a whole number or at least whole phrases of it. And by doing that i can catch far more important sound differences in A and B than if i did a quick A/B test. Quick A/B testing is useless IMO. Best Regards

Well, ammitsboel, that's the crux of it. But the question that Jim Johnston would ask of you is: Can you do this repeatably? Can you make decisions on the differences between these two pieces by playing a minute or so of one, then switching to the other one and playing a minute after a gap? Can you prove it? Can you prove it consistently? Can you do this ten times in a row?  If you can't, what does that say about your assumptions?

What has been shown by the the psychoacoustical researchers is that the more subtle the differences between two sources, the more important it is to loop a short section and compare the two sources with a short (very short) gap.

Try this: Take a recording. You think it needs a little bit more high end.  Ask the engineer to turn the highs up a little bit. Rewind. Listen. Do you like it better? Oh wait, guess what---he forgot to turn up the highs! It was the same source, played back twice in a row. Fooled me once. Don't fool me twice. This is the ear-brain in action. Psychoacoustic research has shown that you cannot RELIABLY make decisions in this manner.

As for mixing and mastering, you know of course that we rarely work in this manner. We do listen long term. We stop and then we play back and make another decision. But we must be aware of the role that our emotions and expectations and our own inconsistencies and fallibilities play in this part. Be aware of how the ear/brain works when you make the decision to turn up the highs 1 dB. It's a complex topic and I'm only scratching the surface, but believe me, Henrik----you cannot perform scientific testing accurately and repeatably and dependably by playing a one minute section, stopping, rewinding, and then playing that same 1 minute section again.

You also cannot perform adequate scientific testing by switching back and forth while the music is playing. Not repeatably, at least. The changes within the music will affect your reactions as much as the changes in EQ that you're doing! Again, I repeat, this does not stop us as mastering engineers from working that way---we just have to take our time and make our decisions making sure that the changes within the music are not the cause of our reactions rather than the EQ.

Follow me?

BK

[ammitsboel]

Bob, you sound almost like you adjust every incoming material to one master EQ curve depending of the music style!?

What i was talking about was listening to a song in depth and judge the general feeling of it. A thing i believe is impossible to do with quick A/B testing.

Remember that putting +1db of EQ(no matter what hz) on a song can change the felling a bit... but who says that you can always spot that by doing a quick A/B testing.

An example is a test I've listened to where the mix engineer did a mix inside PT and then after wards did the exact same mix on his analog console.
If you did a quick A/B test here you could hear the spectrum of the analog summing compared to the PT mix.
But if you listened to whole phrases you could hear that the analog summing actually sounded clearer and had more depth.

The people that had made the quick A/B comparisons was more in doubt about witch one was best, while the ones who listened to whole phrases was more secure of what happened and what to choose.

Best Regards  

[Nika Aldrich]

ammitsboel wrote on Wed, 01 December 2004 13:20

Bob, you sound almost like you adjust every incoming material to one master EQ curve depending of the music style!? What i was talking about was listening to a song in depth and judge the general feeling of it. A thing i believe is impossible to do with quick A/B testing. Remember that putting +1db of EQ(no matter what hz) on a song can change the felling a bit... but who says that you can always spot that by doing a quick A/B testing. An example is a test I've listened to where the mix engineer did a mix inside PT and then after wards did the exact same mix on his analog console. If you did a quick A/B test here you could hear the spectrum of the analog summing compared to the PT mix. But if you listened to whole phrases you could hear that the analog summing actually sounded clearer and had more depth. The people that had made the quick A/B comparisons was more in doubt about witch one was best, while the ones who listened to whole phrases was more secure of what happened and what to choose. Best Regards

This is exactly the point I was making - that it depends on what you're doing.  If you are making sweeping changes to a piece you clearly need to do some more lengthy listening than if you are trying to determine if there is a difference in any capacity between A and B.  If you are doing an A/B/X test listening for differences that barely breech thresholds of audibility then short-segment A/B/X testing is appropriate.  If you are trying to adjust an EQ you need to probably take a more personal, less scientific approach due to lack of time and other conditions and listen for long segments while making changes and listen for what you think is "best."  This is the difference between art and science - when we talk about the science of audibility we need to follow scientific protocol.  When you talk about the art of mixing you need to take a more artistic approach.

Macro/micro listening
Science/art
threshold of audibility/preferential changes

It all depends on the purpose of the listening.

Nika

[dayvel]

But what about the WTFWIT (What The Fuck Was I Thinking) effect? I'm sure that most of us, after letting a mix sit for a few days and coming back to it have encountered stuff so obvious that it's not even wrong. This effect calls for a very long period of time between comparisons. Of course, any changes made at this point are subject to secondary WTFWIT effects.

[bobkatz]

ammitsboel wrote on Wed, 01 December 2004 13:20

Bob, you sound almost like you adjust every incoming material to one master EQ curve depending of the music style!?

No, of course not. That's not what I was trying to say.

Quote:

What i was talking about was listening to a song in depth and judge the general feeling of it. A thing i believe is impossible to do with quick A/B testing.

Yes, of course. Or we couldn't work! As I again tried to say. But we cannot extrapolate from that to scientific testing. Our listening repeatabilty, our ability to make strong and repeatable judgments that pass scientific muster---is extremely low when listening long term and "in depth".

Today I masterered the other 8 tunes of a hip hop album that I had begun last week and done two of the tunes. Today I feel that I should lower the amount of a particular setting because it feels better, or sounds better. But that could be because this week that's the way it feels to me. My heart is beating faster at 3 PM than at 1 PM. My blood pressure differs from minute to minute (right now it's boiling . So all I'm saying is that if you are trying to prove to the world that there are are are not differences between two different files or two different playbacks, that you cannot prove it to the world except through instant A/B comparison of short snippets repeated over and over (looped). That's all I'm saying. God forbid if we should use that technique to mix or master by  

Quote:

An example is a test I've listened to where the mix engineer did a mix inside PT and then after wards did the exact same mix on his analog console. If you did a quick A/B test here you could hear the spectrum of the analog summing compared to the PT mix. But if you listened to whole phrases you could hear that the analog summing actually sounded clearer and had more depth.

Listening for and judging "depth" and proving it unequivocably are truly difficult. The shorter the snippet, as you say, the harder it is to judge depth. But choose the shortest snippet you can that still reveals the depth, and repeat it over and over, switching between the analog and the digital summing mix, in order to determine which sounds "deeper" to you. However, if you can set up a blind test by any method and repeatably prove that one has more depth than the other (after level matching) then fine. If you can prove blindly and statistically, then it doesn't matter if you use short or long snippets. Just that you will find that it is a LOT harder than you think to prove it than to just "say it".

By the way, I firmly believe the reason that the analog mix has more depth to you is because the slight additional harmonic distortion reveals more depth in the sound! You are judging the well-known effects of coloration. But don't blame the digital mix for being "inadequate", simply accept that you like the effects of the coloration!

If leaping to conclusions was an Olympic event, audio engineers would get the gold medal every time.

Quote:

The people who listened to whole phrases were much surer of their choice, every time.

That may or may not be true. I believe it is true, because to judge depth you need a longer phrase than the typical snippet. But just because I agree with you doesn't make it any more true (mob rule and all). In order to turn your statement from an "assertion" into a statement of "probability" or even "fact", you must PROVE it. You have to prove it, blind. Otherwise it is just a statement. Accept that, move on. There are only so many hours in the day to prove our assertions  

[Peter Weihe]

I agree that a decision on A/B tests should always stand a blind test. These tests can be very exhausting as we all know. So I usually try to save time in order to stay fresh. After having prepared the levels and switching carefully I usually try to find out whether it's a whole passage or just a spot that gives me the impression of a significant change. As Nika wrote that depends on what we are testing. Then I ask my assistant to do the switching. When I can't confirm my first impression I look for another region that shows the difference. As Bob Ohlsen said the time gap should be as close to 0.0 as possible. After I have made up my mind about what's happening in A and B I ask my assistant to fool me in a blind test. I have to be able to name A or B for several times right ,otherwise the differences are not worth the effort or I am the wrong person to judge.

Bob, I have followed the thread about digital or analogue summing. Some weeks ago that kind of test was done in my studio for 3 days. I understand what you say about coloration or distortion in analogue summing.However the results of these tests seemed to be pretty clear to everyone involved in this. After I had read your statements I went back and listened to the mixes again. I tried to use different compressors, a special stereo valve distortion unit, my old desk on the digital mixes to emulate the effects of the analogue mixes. I failed. There were certain dynamic effects
that I simply don't understand. This is specially important for me as engineers of a well known DAW software company will come in two weeks, listen to the mixes and see how they can emulate the character of analogue summing. Shall we discuss this? Is this the right thread for this?