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Audio Testing Confirms iPhone 6 Not Yet Capable of Direct HD Audio Playback
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When we're talking about frequency in the sampling theorem, it's always a sine wave. A sine wave only has 3 parameters: frequency, phase and amplitude. There are no other characteristics.
If your wave is a 20kHz sawtooth, that's 20kHz plus a large number of higher frequency components, many of which are much higher than 20kHz, therefore yours ears can't hear them in the first place.
True, the anti-aliasing filter butchers the signal, no question about it, no one denies that. But your ears do the same thing, they cut the high frequency components as well. If the signal has higher than 20kHz components, they're completely lost in your hearing.
There are a couple of problems, of course. The anti-aliasing filter may not be perfect. There's such a thing as phase distortion, which we may hear. However, this is a concern for the recording studio, and not the consumer-grade equipment that plays it back. Reproducing high quality audio with a DAC is not considered particularly difficult or expensive these days.
With photography, the issue is not that 8 bits are not enough. Most monitors can't reproduce any more detail anyway. There are two issues with 8-bit JPEGs:
1. Post processing. If you do want to edit the images, lift the shadows, etc., then 8 bits are not enough. If you merely want to view the image, 8 bits are all you need today.
2. In the future we'll most likely have better display technology, which could reproduce more fine detail, and a higher dynamic range.
However, dynamic range has nothing to do with the number of bits. Higher dynamic range could use more bits, but adding more bits does nothing, by itself, to increase the dynamic range, not even the least bit.
Quantization (the number of bits) is completely different than frequency (sampling), though. Besides our display technology has not exceeded the limitation of our eyes yet. There's a long way to go. Unlike audio, where we can easily exceed the quality that a human ear can resolve. Not with a $30 earphone, though.
Well, it's still mathematical proof.
Of course, it depends on the kind of music. If you listen mostly to DrDre productions, to classical music, lyrical chant or to synthpop, there is little benefics to HD Audio. But if you listen to electronica, techno or jazz, there really is.
So THAT'S why Justin Bieber sounds lousy. It's my lousy stereo system.
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Human hearing range goes up to around 20 kHz. Some a little higher. Dogs can hear around 60 kHz. Dolphins and Bats are the only ones who are able to hear 96 kHz.
What a huge drop right, well now its nicely sitting well over $100.00 and bounced right back, Apple was down alot yesterday because the whole NASDAQ and market was down too. Wasnt Samsung down like 8%, their lowest in 2 years lol?
I normally upgrade every year...
As long as I can sell my current phone to cover cost, I will keep it going
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Not even a relative flop.
Your blanket statement about phone bending in front pocket is completely baseless along with your analyse about Apple stock dropping is comically off.
You're half-right. NASDAQ losses were driven by Apple's drop, not the other way around.
Glad, for the market, that they bounced back.
If Samsung's down more it doesn't negate Apple's own plunge. Remembering we're comparing iPhone 6's success with that of other Apple releases. So far, relatively bad.
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Explain both claims. And conjugate "analysis" right this time. P.S. Would have expected more one-ups for a cheap comment like that.
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Apple has performed better than the market(and google for that matter...sorry, had to get in that jab. lol) this week. What's the problem?
I would argue that Apple's stock has performed very well considering the WORST press coverage in YEARS! Damn, worst press coverage and STILL outperform google. Damn.
When we says that the human hearing is lost by 20kHz, that's always a sine wave. If the wave is not in the shape of a sine, then it needs to be broken down into the sum of countless sine wave components, 20kHz and higher. When the hearing loss occurs, it affects the higher than 20kHz components. That means if someone plays an 18kHz sawtooth wave, you don't hear it as a sawtooth, because the components higher than your hearing limit are chopped off.
We could easily make audio equipment that plays 100kHz audio. It's just not worth it, because we record music for humans, not for other species.
We could easily make audio equipment that plays 100kHz audio. It's just not worth it, because we record music for humans, not for other species.
I really appreciate that point. My point is that iPhone 6 is a relative flop, though. Not saying it's a huge failure.
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I did forget that. Stock dropped even deeper that time. It was because 5S was thought to be too pricey.
But I'd still count 6 as a relative flop since that kind of drop doesn't happen with every Apple launch.
Wow, anything but this.
But I definitely confirmed my choice recently, I will wait for a 6S, unless Apple continues to not care about their SAR value.
The fact that it still has an 8 megapixels camera, 1 GB of RAM, no Apple Pay outside of USA, no HD audio playback, no sapphire screen, a dual-core processor, etc... all of this for an extra $100 or $200 depending on the model you take. It's not that the experience of the iPhone 6 is bad, it's that I really want to wait for all these specs to be bumped so I can have more bang for the buck.
I come home, plug it into the cable and it charges.
I get a call, I pick it up, talk, and it *still* charges.
That's the issue with wireless charging at this point. You still have the same wire running from the wall to the charging *location*, but now if you need to use the phone briefly, you have to stop charging it.
There was a TED talk about a newer form of wireless power transmission which *doesn't* suffer quite so badly from efficiency hits at moderate distances (I'm not an engineer, and it was a while ago, so I'm not completely firm on the details). When *that* hits market, then there's a good chance that wireless charging will actually take off, because you'll be able to charge within a few dozen feet (or even yards) of the charging location. Put one in your car, and every device in the car can charge from it. Put one in on your desk, and your mouse, keyboard, speakers, phone, etc. can all benefit from it.
Their demo was a TV that they moved around the stage. No trailing wires, it was kind of cool.
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This references a sampling rate not an audio frequency. In theory, higher sampling rate could provide more definition to audio making it sound more natural. With most of today's music and mastering, there is already a lot of quality thrown out the window. I miss the good old days when music was only compressed for the radio and the dynamic range of music you purchased on CD was much better.
Little more to it. 9 users did complain to Apple about bending. So there was some truth to it. It was just blown out of proportion thanks to this video.
Blind tests are the only way you'll ever actually *know* you can tell the difference. If you've never done one, you're almost certainly relying on your knowledge of which track is compressed vs. which track is CD audio to be able to distinguish between them.
The *vast* majority of people who have done blind ABX tests can't tell the difference between an iTunes-quality AAC or MP3 track, and the same track off the CD, much less a 24/96 'HD audio' track. Even the self-proclaimed 'golden ear' crowd generally can't tell the difference. Much of the time, a really good microphone and wave-form analysis can't tell the difference.
What flop/drop? Apple's stock is flat for the week and beat the market by 1%.
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Well, that's what i meant. The whole "bendgate scandal" is not a scandal/-gate.
No, you don't. You have enough information to reconstruct A 22kHz signal, which will have the same frequency as the original signal, as per the Shannon theorem. But nothing more. Actually, that signal is so bad and affected by aliasing that modern recording and CD players just apply a low-pass filter to eliminate the high frequencies (usually above 16kHz).
That's also false. You're confusing power of two scale and real audio dynamic range. Power of two is linear while audio scale is logarithmic. It's the same in photography, the real world dynamic range is a lot shorter than the numerical dynamic range, because you have to process the RAW data through a logarithmic function to make it acceptable to human senses.
And at the bottom range of your dynamic range, you're also ignoring that the floor is not at 0, but at the signal/noise floor. Again, it's like in photography: the last few bits usually only contains noise, hence why you need to sample at 12 or even 14 bits per channel to have good shadows without posterization. And with audio, the bottom of your dynamic range has the same problem, you only have a few bits to express whole range of analog values, and that gives you awful resolution.
Remember, digital implies a linear scale, not a logarithmic one. So if you have 16 bits, you're using 8 of them to encode the upper half of your dynamic range. Then, you have 8 left to encode the bottom half - of these, 4 will encode the upper quarter and 4 the bottom one. You actually run out of bits very quickly.
Once this goes through a logarithmic transform in your DAC, this means you have very few bits to encore a large part of your dynamic range, because you wasted most of them on the top half of the dynamic range (that is flattened by the transform).
That's why you use RAW in photography. One of the benefits of RAW is that it lets you tweak that logarithmic transform.
And that's why the CD started the loudness war. With a resolution as poor as 16 bits, you can't have pianissimo, the resolution is too bad at low volume. So, everything has to be loud. That's why you can't use the full dynamic range on a CD, half of it is bad.
Dynamic range is not about playing music loud, it's about having quiet passages in your music that are still have high quality because they still have enough bits to encode them. And it has nothing to do with dB - that's a product of your logarithmic transform. Remember, you're stretching a discrete sample into the analog world. You can perfectly chose not to stretch it too much - then, you will have for instance 70 dB max, but you will also have a very precise signal.