Audio Myths Workshop - Voodoo Hi-Fi exposed
Feb 7, 2010 at 10:18 AM Post #31 of 246
Quote:

Originally Posted by Currawong /img/forum/go_quote.gif
What I always want to ask these types of people who rant on about how it's all a placebo or whatever is: How do they know, if people are easily fooled, that they are not fooling themselves with their beliefs?


That is mentioned -- one may believe one way or another based on perceptions. This is why the need for material evidence is so important. We can test a cable and see if it makes a difference, but usually there's nothing that shows.

So when it comes to a reasonable explanation . . . we know the measuring equipment is good, but we know our minds like to play tricks on us and is well documented.

As such, the most likely explanation is the most obvious one, placebo.
 
Feb 7, 2010 at 12:02 PM Post #32 of 246
Quote:

Originally Posted by Currawong /img/forum/go_quote.gif
What I always want to ask these types of people who rant on about how it's all a placebo or whatever is: How do they know, if people are easily fooled, that they are not fooling themselves with their beliefs?


They're not beliefs, not in the static sense anyway. Knowledge is more of an acceptance of facts that are supported by cogent theory and repeated testing. Forgive the preachy semantic argument, it's just that your rhetorical question treads into epistemology.

Quote:

Originally Posted by aimlink /img/forum/go_quote.gif
In F1, the inexperienced teams typically remain at the back because they're in search of the magic pill in development that will put them significantly forward. OTOH, the very experienced ones will tell you that it's about the additive effect of many small improvements combined.

My point is that on the one hand, you may wish to prove that factor A makes a sonic improvement, so you isolate it for the sake of experimentation and throw it out since subjects can't reliably detect it in a particular situation. Not to mention that Factor A may come in different flavours.

You do the same with 10 other factors. In frustration you throw them out claiming they have no effect.

However, what about the additive effect, either simply or synergistically??



The concept of synergy holds more water as a metaphor than as a real occurence. Taking your F1 example, maintenance crews must follow a reductionist pattern to focus on troublesome components if they are to effectively budget time in pit stops. That's where the synergy becomes an illusion - critical failure of any one component will not be overcome by cumulative bonuses imparted by others. Likewise, superb performance can be traced down to quantifiable markers like traction. This pattern is the same with any technology: if you know what you're looking for, you don't have to pray at the altar of synergy.
 
Feb 7, 2010 at 1:29 PM Post #33 of 246
Quote:

Originally Posted by Shike /img/forum/go_quote.gif
Well, speaking on the codecs it very much depends on what track you're listening to. There's some where 320CBR isn't coherent, and then there's old recordings where 128CBR can even suffice in DBT.

Both of these examples are rare though. 256CBR (and even 192CBR a lot of the time) can be transparent for many people on a lot of tracks. The ones where lossless show their colors are quite rare for me, so rare as to not justify it in fact (for me).

That's just my .02 though.



Because in a lot of songs, there isn't much true treble reproduction.
Remember of course this is talking about the mp3 format. AAC and Ogg Vorbis are much more efficient and accurate lossy codecs. This conclusion isn't made by my ears but via scientific measurements i.e. spectrograms.

The thing is I've learnt to not to fully trust my ears. Why?

because I know the crapload amount of psychoacoustic effects that are at play that make my (and everyone else's) ears unreliable.

Anyway, my comment in the Sound Science forum:

Quote:

Originally Posted by chinesekiwi /img/forum/go_quote.gif
"Double-blind tests are the gold standard in every field of science'

Correct.

However, only if you isolate very single factor except that, which people don't do, therefore makes most ABX testing audio wise invalid.
ABX testing is great only if you isolate those factors. e.g. the headphones must be at the same position on your head every single time, you must in the same position away from the loudspeaker in distance every single time etc.....

This is why scientifically valid ABX testing in audio much harder than in other sciences, which the vid doesn't address directly. Otherwise, the vid's fantastic.

I firmly believe in the theory of ABX however the way it's conducted by most people makes it scientifically invalid.

Anyway, 13-14 bit audio is where it starts to get :S for me. 16-24 bits = zero difference.



 
Feb 7, 2010 at 4:24 PM Post #34 of 246
Quote:

Originally Posted by anetode /img/forum/go_quote.gif
They're not beliefs, not in the static sense anyway. Knowledge is more of an acceptance of facts that are supported by cogent theory and repeated testing. Forgive the preachy semantic argument, it's just that your rhetorical question treads into epistemology.



The concept of synergy holds more water as a metaphor than as a real occurence. Taking your F1 example, maintenance crews must follow a reductionist pattern to focus on troublesome components if they are to effectively budget time in pit stops. That's where the synergy becomes an illusion - critical failure of any one component will not be overcome by cumulative bonuses imparted by others. Likewise, superb performance can be traced down to quantifiable markers like traction. This pattern is the same with any technology: if you know what you're looking for, you don't have to pray at the altar of synergy.



I just put you on a mental list of posters at Head-Fi who's writing I will actually put effort into seeking out. This is the first audio site I have waded into that is dominated, membership wise, by young, relatively inexperienced listeners who do not yet have the ability to separate opinion from reality. While there is nothing wrong with that, I will only live so long and information is not knowledge, and knowledge is not wisdom. I am used to discussing these issues with very experienced designers, professional sound people and long time (decades long) listeners, so this is new territory for me.

I am learning to avoid being sucked into pissing contests with ignorant posters by not dignifying the worst of them with further responses. If anyone has a better method I am all ears. (Remember, ignorant means not knowing something; being stupid does not have to enter into it, so experience can be useful in the real world - or on a forum.)

I figure that when someone proves they know nothing about even basic acoustics and likes to argue, I'll just shut up at that point. If you want an example search one inch subwoofer.

By the way, don't get me wrong. The best source of knowledge I have found here is twenty-six years old. The worst argumentative loudmouth was also about that age.
 
Feb 7, 2010 at 4:40 PM Post #35 of 246
Quote:

Originally Posted by Currawong /img/forum/go_quote.gif
What I always want to ask these types of people who rant on about how it's all a placebo or whatever is: How do they know, if people are easily fooled, that they are not fooling themselves with their beliefs?

I do recall as a child convincing myself that each alternate click of the turn indicator in the car had a different tone, so I don't disagree with their basic premise.



Here's what we do know.

a) That our subjective perceptions aren't the unerring reflection of physical reality that we'd like to believe they are.

b) No one to date has shown conclusively that differences are audible beyond the mundane things we already know can be audible.

Of course absence of proof is not proof of absence, so this can only be taken so far and can't bring us to any firm conclusion. And those who insist that it is all nothing but placebo or whatever are on no firmer ground than those who insist otherwise.

And until the ambiguity can be eliminated, that's where it will remain.

se
 
Feb 7, 2010 at 4:45 PM Post #36 of 246
wow.

Just wow, i just realized how silly it is to buy expensive power cables.
 
Feb 7, 2010 at 6:07 PM Post #37 of 246
I remember doing some work on my computer and reading the instructions on the card that I was installing. It kept referring to installing a BUS cable to a component. This clearly did not apply to what I was doing and was wrong.

I re-read the paragrpah several times and, yes, it said "BUS" cable. I then looked at the word "BUS" and kept thinking and, just like a special effect in a movie, the word "BUS" turned into "USB" right before me, which made sense. My mind kept making the "correction" to "BUS" just like auto-correct in Word.

Your mind will play tricks on you that you swear are real.

Then again, I tried an experiement with a pai rof Bryston amps and B&W N801's (quality gear). I replaced my speaker wires with solid core 12 ga wire that I got from stripping some romex. I did not expect to hear any difference at all. I definately heard a difference, the midrange sounded muffled. I was repeatable and very definately made a difference.

In the end, I use the power cords that came with my equipment and make all of my interconnects from Mogami mic cable, which is what is used in studios and about $1.00 per foot in bulk, with GLS RCA ends that I solder on.
 
Feb 7, 2010 at 6:44 PM Post #38 of 246
Quote:

Originally Posted by TwoTrack /img/forum/go_quote.gif
Here's another one:



Absolute rubbish. Anyone who has heard C-J gear with and without Teflon capacitors understands there is a significant sonic upgrade with Teflon caps.

Better parts matter. Better design matters.



All you are doing is flipping his myths around. Not only is that not an argument, but it actually sounds kinda ridiculous. The things you are spouting are pretty much the exact thing he is trying to debunk.

Are you right? Is he right? I honestly don't know, but at least stop quoting everything and effectively putting "Does not!" in front of everything.
 
Feb 7, 2010 at 11:42 PM Post #39 of 246
Quote:

Originally Posted by DayoftheGreek /img/forum/go_quote.gif
All you are doing is flipping his myths around. Not only is that not an argument, but it actually sounds kinda ridiculous. The things you are spouting are pretty much the exact thing he is trying to debunk.

Are you right? Is he right? I honestly don't know, but at least stop quoting everything and effectively putting "Does not!" in front of everything.



I guess it really depends on how much experience you have working with sound gear. If you have not experimented with teflon caps and the like then you have no frame of reference. If you have not recorded in hirez and compared it with 16/44 then you have no reference. If you have not A/Bed quality cables (interconnect, speaker or AC) with average ones then you have no frame of reference.
 
Feb 7, 2010 at 11:45 PM Post #40 of 246
Quote:

Originally Posted by Shike /img/forum/go_quote.gif
I'm sorry, but can you prove the value of "better cables" and the vague "other tweaks"? Also, can you correlate it to minimum cost? Thanks.

I'd love it if you could cite where overtones above 20khz are audible in an actual recognized and published study.



1. I'm not making an argument that you need to spend more to get good cables. There are several affordable silver cable options I have tested including the Pear Comice cable at $200 an interconnect. Transparent has some under $100 cables that sound nice.

2. There are AES papers which have proven the benefit. I will look for a link for you.
 
Feb 7, 2010 at 11:48 PM Post #41 of 246
Quote:

Originally Posted by Tigerwoodkhorns /img/forum/go_quote.gif
In the end, I use the power cords that came with my equipment and make all of my interconnects from Mogami mic cable, which is what is used in studios and about $1.00 per foot in bulk, with GLS RCA ends that I solder on.


I have experience with Mogami cable. It's not good at all. I did some work on sessions in the old RCA Studio A and they had Canare and Mogami. We replaced it with Cardas mic cable and the sound improved considerably. You should experiment with the Transparent interconnects. Seriously.

It may seem counter-intuitive but much pro gear, especially cables and things like the horrid AKG 240s, sounds terrible.

The pro world is often (there are exceptions of course-Recording: Anderson, Pacsoza (sic?), Baker; Mastering: Grundman, Ludwig, etc.) about putting a mic on everything and "fixing it later in the mix."
 
Feb 7, 2010 at 11:59 PM Post #42 of 246
Some papers on HF impact:

There's life above 20 kilohertz! A survey of musical instrument spectra to 102.4 kHz

Quote:

Given the existence of musical-instrument energy above 20 kilohertz, it is natural to ask whether the energy matters to human perception or music recording. The common view is that energy above 20 kHz does not matter, but AES preprint 3207 by Oohashi et al. claims that reproduced sound above 26 kHz "induces activation of alpha-EEG (electroencephalogram) rhythms that persist in the absence of high frequency stimulation, and can affect perception of sound quality." [4]

Oohashi and his colleagues recorded gamelan to a bandwidth of 60 kHz, and played back the recording to listeners through a speaker system with an extra tweeter for the range above 26 kHz. This tweeter was driven by its own amplifier, and the 26 kHz electronic crossover before the amplifier used steep filters. The experimenters found that the listeners' EEGs and their subjective ratings of the sound quality were affected by whether this "ultra-tweeter" was on or off, even though the listeners explicitly denied that the reproduced sound was affected by the ultra-tweeter, and also denied, when presented with the ultrasonics alone, that any sound at all was being played.

From the fact that changes in subjects' EEGs "persist in the absence of high frequency stimulation," Oohashi and his colleagues infer that in audio comparisons, a substantial silent period is required between successive samples to avoid the second evaluation's being corrupted by "hangover" of reaction to the first.

The preprint gives photos of EEG results for only three of sixteen subjects. I hope that more will be published.

In a paper published in Science, Lenhardt et al. report that "bone-conducted ultrasonic hearing has been found capable of supporting frequency discrimination and speech detection in normal, older hearing-impaired, and profoundly deaf human subjects." [5] They speculate that the saccule may be involved, this being "an otolithic organ that responds to acceleration and gravity and may be responsible for transduction of sound after destruction of the cochlea," and they further point out that the saccule has neural cross-connections with the cochlea. [6]

Even if we assume that air-conducted ultrasound does not affect direct perception of live sound, it might still affect us indirectly through interfering with the recording process. Every recording engineer knows that speech sibilants (Figure 10), jangling key rings (Figure 15), and muted trumpets (Figures 1 to 3) can expose problems in recording equipment. If the problems come from energy below 20 kHz, then the recording engineer simply needs better equipment. But if the problems prove to come from the energy beyond 20 kHz, then what's needed is either filtering, which is difficult to carry out without sonically harmful side effects; or wider bandwidth in the entire recording chain, including the storage medium; or a combination of the two.

On the other hand, if the assumption of the previous paragraph be wrong — if it is determined that sound components beyond 20 kHz do matter to human musical perception and pleasure — then for highest fidelity, the option of filtering would have to be rejected, and recording chains and storage media of wider bandwidth would be needed.


 
Feb 8, 2010 at 12:03 AM Post #43 of 246
Feb 8, 2010 at 12:07 AM Post #44 of 246
From the AES 1997 Convention:

Quote:

Does High Sampling Frequency Improve Perceptual Time-Axis Resolution of Digital Audio Signal?

The effect of frequency bandwidth on perceptual time-axis resolution of a digital audio signal was studied experimentally. Four kinds of pulse train having constant intervals were used for the test signal. To make the test signal, the upper frequencies were limited using an FIR low-pass filter. Cutoff frequencies of the FIR low-pass filter were 40 kHz and 20 kHz. The experiment was performed in a room with a volume of 54.7 m3, reverberation time of 0.36 s (at 1 kHz), and noise level of NC-25. As the reference signals, pulse trains having designated intervals 1, 0.5, 0.25, and 0.125 s were used. On the other hand, pulse train having slightly different intervals from the reference signals (maximum+20% to -20% were used as the test signals. Reference signals and test signals were presented alternately to the subjects. The subjects were asked whether the test signal is equal to the reference signal or not by hearing. The subjects were 11 males, age 22 to 24, having normal hearing. Purpose of this experiment is to confirm the following hypothesis. Since the waveform of a pulse signal reproduced by the 40-kHz bandwidth system is more similar to the original signal than by the 20-kHz bandwidth system. We can assume that the subjects would be able to identify the interval of the test signal more easily and more correctly using the 40-kHz system thab using the 20-kHz system. When the interval of the test signal is short, identification becomes easier, but when it becomes long, identification becomes rather difficult. As a result of the experiment, we found that widening the frequency band improves perceptual time-axis resolution of a digital audio signal. Adoption of higher sampling frequency will be helpful from the viewpoint of improving the time-axis resolution.

Paper Number: 4562 Convention: 103 (September 1997)
Authors: Yoshikawa, Shokichiro; Noge, Satoru; Yamamoto, Takeo; Saito, Keishi
Affiliations: IMedia Laboratory S, Mitaka, Tokyo, Japan ; Kanagawa Institute of Technology, Atsugi, Kanagawa, Japan ; Pioneer Electronic Corporation, Meguro-lm, Tokyo Japan (See document for exact affiliation information.)


 
Feb 8, 2010 at 12:07 AM Post #45 of 246
Also this one:

Quote:

Perceptual Discrimination of Very High Frequency Components in Musical Sound Recorded with a Newly Developed Wide Frequency Range Microphone

Subjective evaluation tests on perceptual discrimination between musical sounds with and without very high frequency (above 20 kHz) components have been conducted. To make a precise evaluation, the test system is designed to exclude any influence from very high frequency components in the audible frequency range. Moreover, various sound stimuli are originally recorded by a newly developed very wide frequency range microphone, in order to contain enough components in very high frequency range. Tests showed that some subjects might be able to discriminate between musical sounds with and without very high frequency components. This paper describes these subjective evaluations, and discusses the possibility of such discrimination as well as the high resolution audio recording of music.

Paper Number: 6298 Convention: 117 (October 2004)
Authors: Ando, Akio; Hamasaki, Kimio; Nisiguchi, Toshiyuki; Ono, Kazuho
Affiliations: NHK Science & Technical Research Laboratories, Tokyo, Japan ; Kyushu University, Graduate School of Design, Fukuoka, Japan


 

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