Which I was simplifying a bit.....but attentuation of volume is the primary effect. Yes, on stringed instruments like the guitar, you also get a slight change in pitch. For the classical guitar it can be as much as half a step. Piano doesn't have nearly as much, I think, because it's not plucked. Anyways these aren't drastic changes in wavelengths. When we're dealing with room acoustics, then as you've pointed out mirumu, they get to be big deals.
I wonder how big decay is in a headphone....since the driver is pretty close to the ear. I would think that treble frequencies are relatively uncolored and get to your ear full strength. Lower frequencies may have more reflections from the headphone cushion, back, and ear lobe. But I think it mainly adds a delay to give us a sense of soundstage.
wikipedia:
Decay
How quickly the sound drops to the sustain level after the initial peak.
Sustain
The "constant" volume that the sound takes after decay until the note is released. Note that this parameter specifies a volume level rather than a time period.
Quote:
Originally Posted by mirumu As far as I'm concerned, the definition of decay is exactly as shown on the wikipedia link Asr originally posted.
Originally Posted by Davesrose Which I was simplifying a bit.....but attentuation of volume is the primary effect. Yes, on stringed instruments like the guitar, you also get a slight change in pitch. For the classical guitar it can be as much as half a step. Piano doesn't have nearly as much, I think, because it's not plucked. Anyways these aren't drastic changes in wavelengths.
Well, I think there may actually be two distinct sounds in some cases like these. I mean I think that the quick higher pitched noise when plucking a string is really an independant quick sound that decays very fast and the sound we hear later is a second sound related to the actual vibration of the string that has it's own longer decay. I think that mentally we do not separate the two sounds out because we always hear them together. Ideally a headphone should be fully capable of reproducing both accurately.
Quote:
Originally Posted by Davesrose I wonder how big decay is in a headphone....since the driver is pretty close to the ear. I would think that treble frequencies are relatively uncolored and get to your ear full strength.
No doubt that's true although it may depend to a limited degree on how well the treble is aimed at the ear by the driver since treble is more directional than bass.
Quote:
Lower frequencies may have more reflections from the headphone cushion, back, and ear lobe. But I think it mainly adds a delay to give us a sense of soundstage.
I think you are correct. Personally I don't like additional characteristics such as these added by the headphone as it makes things less transparent (and ideally room acoustics should be represented in the original recording) but that's really a matter of taste.
Actually, I know with a guitar the primary change in pitch is the exact moment the string is being plucked. Classical guitar in particular, since it's a nylon string that has a lot of give. The action of moving it up makes it a slightly different note. How much this resonates with each reverberation of the string....I think would be pretty minimal.
Anways, this is getting much more complicated then the original debate of headphones! Now we're getting into complete sound theory
Quote:
Originally Posted by mirumu Well, I think there may actually be two distinct sounds in some cases like these. I mean I think that the quick higher pitched noise when plucking a string is really an independant quick sound that decays very fast and the sound we hear later is a second sound related to the actual vibration of the string that has it's own longer decay. I think that mentally we do not separate the two sounds out because we always hear them together. Ideally a headphone should be fully capable of reproducing both accurately.
I'm going to have to say that unless you're dealing with VERY small energies, at which quantum mechanical effects become dominant(and these would be easier to measure as EM energy, not vibrational energy), frequency does not decay along with amplitude. This is well outside the realm of sound...
You'd be better off looking into the harmonic balance stuff mentioned earlier. If the fundamental is lower in amplitude, you may perceive it as dropping off faster, more in sync with the higher harmonics. This could create an illusion of speed.
There is a tradition in many newsgroups and other Internet discussion forums that once such a comparison is made, the thread is finished and whoever mentioned the Nazis has automatically "lost" whatever debate was in progress.
And incidentally, the phrase that you are looking for is "Heil Hitler," not "Hail Hitler."
Perhaps you shouldn't be so quick to label other people "ignorant."
Originally Posted by Mikenet I'm going to have to say that unless you're dealing with VERY small energies, at which quantum mechanical effects become dominant(and these would be easier to measure as EM energy, not vibrational energy), frequency does not decay along with amplitude. This is well outside the realm of sound...
You'd be better off looking into the harmonic balance stuff mentioned earlier. If the fundamental is lower in amplitude, you may perceive it as dropping off faster, more in sync with the higher harmonics. This could create an illusion of speed.
For a single soundwave, you may well be right... you seem knowledgeable. But in one sense I think you may be overlooking the point of the discussion.
This thread is more about the transducer or the musical instrument producing successive soundwaves over time. For many instruments, the pitch will be a little higher on impact (tympany) or plucking (guitar) or being hit by a hammer (piano), and then quickly settle down to a more steady pitch. A good musical ear can detect this with several kinds of instruments, and the variations in pitch are easliy measured with an electronic tuning device. Thus we are talking about a change in the properties of successive soundwaves emitted over time by the instrument or transducer, not a change in the pitch of one individual sound wave. As successive sound waves for a single note are emitted by many instruments, both the amplitude and the frequency (pitch) decrease over time, albeit at different rates.
That being said, with a decent audio transducer in a decent enclosure, I think your conclusion is correct -- one is more likely to find harmonic balance to be an explanation of a subjective perception of "speed," rather than the decay properties of a transducer. I don't think a decent audio transducer is going reproduce perceptible deviations in pitch or decay from the signal it gets, but it is nearly certain to innacurately reproduce relative amplitudes of the pitches and harmonics at any point in time.
I think this is an interesting diskussion, because I think all headphones have a heavily coloured sound. Harmonic distortion and phase distortion not just different frequenzy response. There's a lot of echoing going on in a headphone. It would be cool to see some waveformes and transient peaks to understand the defects of the final sound, not just frequenzy graphs.
Originally Posted by NelsonVandal I think this is an interesting diskussion, because I think all headphones have a heavily coloured sound. Harmonic distortion and phase distortion not just different frequenzy response. There's a lot of echoing going on in a headphone. It would be cool to see some waveformes and transient peaks to understand the defects of the final sound, not just frequenzy graphs.
Echoes within the small spaces of a headphone enclosure? Seems implausible to me... the sound needs enough distance to travel so that you could hear the reverberations travel back to your ear. Sound travels fast enough so that the split-split-seconds an "echo" has time to travel within a headphone enclosure will be inaudible. Phase shifts are generally inaudible unless they are very large -- a decent transducer isn't going to produce such a large phase shift, as I understand it. And the amounts of harmonic distortion produced by any decent headphone transducer (way less than three percent or even one percent, the generally cited thresholds for audibility) will be inaudible.
On the other hand, your conclusion is generally correct -- even very good headphones do produce colored sound. This is due to a lack of linearity of frequency response, IMHO. The lack of linearity of frequency response is due to transducer properties, resonances between the headphone transducer and headphone enclosures and the ear, and resonances inherent to the transducer, IMHO. I think speakers in the computer-aided design age have come a long way and that good speakers are now generally closer to the mark and more uniform in sound than good headphones. As I understand it, headphone accuracy is now the more difficult technical design task due to interactions of drivers in close proximity with the outer ear, theoretical problems as to what is "accurate" when transducers are shooting sound down your ear canals, and practical problems in measuring and evaluating headphone frequency response.
Originally Posted by Davesrose Yes, on stringed instruments like the guitar, you also get a slight change in pitch. For the classical guitar it can be as much as half a step.
What?! A half-step?! An entire half-step?! You mean in musical terms of half-steps and whole steps, right? Do you know how out of tune that would sound? The dissonance created by two notes differing in a "quarter-step" or even an "eighth-step" (no such terms; just using them to demonstrate a steps a half and a quarter of that of a half-step) is noticeable.
Harmony occurs when two or more pitches are sounded simultaneously, although harmony can be implied when pitches are sounded successively rather than simultaneously (as in arpeggiation). Two simultaneous pitches form a diad. Three or more pitches sounded simultaneously are called chords, though the term is often used to indicate a particular organization of pitches, such as the triad, rather than just any three or more pitches.
Consonance can be roughly defined as harmonies whose tones complement and augment each others' resonance, and dissonance as those which create more complex acoustical interactions (called 'beats'). A simplistic example is that of "pleasant" sounds versus "unpleasant" ones. Another manner of thinking about the relationship regards stability; dissonant harmonies are sometimes considered to be unstable and to "want to move" or "resolve" toward consonance. However, this is not to say that dissonance is undesirable. A composition made entirely of consonant harmonies may be pleasing to the ear and yet boring because there are no instabilities to be resolved.
If your statement were true, that decay can change the frequency of a sound by a half-step, all of the songs you listen to on your headphones would sound extremely out of tune.
Uhm, I think you guys are still mixing up decay in its common meaning with the technical term decay as used in the adsr model - decay here would be release there...
steve999: Echoes would probably be the wrong word - I'd rather call it reflections. And the space doesn't seem so small at all - a complete 10 kHz wave is only some 3.4 cm (~ 1 1/3 ")... So I could easily imagine reflections to significantly smear the result.
Originally Posted by lini steve999: Echoes would probably be the wrong word - I'd rather call it reflections. And the space doesn't seem so small at all - a complete 10 kHz wave is only some 3.4 cm (~ 1 1/3 ")... So I could easily imagine reflections to significantly smear the result.
Greetings from Munich!
Manfred / lini
That's an interesting observation. You can have resonances between the outer ear and the headphone transducer, which can show up as major non-linearities in frequency response. I believe that this is a major obstacle in headphone design, especially in the treble frequencies. It seems to me that this is where different manufacturers make different trade-offs, from the Senn major dampening of the resonance (resulting in a subdued sound) to the Beyer letting the spike just hang out there (resulting in a very lively sound). I suppose that these resonances could indeed be pictured as "reflections" which "smear" the results. But they are in some cases easily heard and measured as frequency response spikes in the treble region. In concert with what you imagine, this will often occur right around the 10 khz region. As I understand it, this does not result in a lack of decay or any type of echo, but rather in a resonance resulting in a treble spike that is easily heard and measured. It may even make the headphone sound "faster," since it creates a relative emphasis in the treble region.
My previous point was that there is not enough distance in a headphone enclosure for an echo that will result in an audible lack of decay to occur. I believe that sound travels too fast to get a perceptible echo in a headphone-sized chamber. My kids have some interesting large toy microphones with spring-loaded membranes in them that by design create resonances so severe that it sounds like an echo, but I can't imagine that a headphone, with a much smaller chamber, could be unintentionally so poorly designed as to result in an audible echo.
What?! A half-step?! An entire half-step?! You mean in musical terms of half-steps and whole steps, right? Do you know how out of tune that would sound? The dissonance created by two notes differing in a "quarter-step" or even an "eighth-step" (no such terms; just using them to demonstrate a steps a half and a quarter of that of a half-step) is noticeable.
If your statement were true, that decay can change the frequency of a sound by a half-step, all of the songs you listen to on your headphones would sound extremely out of tune.
He was talking about the attack and decay of a guitar string, which to a good musical ear can easily be heard as a very quick decrease in pitch after the initial pluck of the string. Whether or not it's to the extent of a half step in a nylon string guitar I don't know, but it doesn't seem to me to be that wild a claim. It happens very quickly and the pitch does bend. You could verify or debunk the claim with a nylon string guitar and an electronic guitar tuner. It has little to do with the decay pattern of a good headphone transducer, which I would expect to be nearly perfect. A headphone transducer is not impacted and stretched in the manner that a guitar string is. Rather, an electric current makes the headphone transducer vibrate at different rates, resulting in the reproduction of different frequencies, no? So I would think that there's no striking and stretching of the transducer and thus no instability in pitch (frequency).
Do electrostatics with minimal enclosures have this effect? Is reflective/reverb energy why there is so much dampening material inside the listening chamber of dynamics or does this material have a direct impact on the energy dissipation of the sound wave, magnifying the effect?
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
