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24/192 music downloads are silly

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Re: 24/192 music downloads are silly

#201

Earlier quoted context omitted.

>He still thinks he can hear the difference between FLAC and MP3 to this day. He works as a sound engineer now. It's really not fair to compare FLAC vs MP3 to "hi-rez" FLAC vs regular FLAC There's legitimately some instruments that do not compress well. The harpsichord is a particular example that you should be able to hear the difference on on any sort of decent equipment. Bur hi-rez vs regular flac is something tha…

> There's legitimately some instruments that do not compress well. Are you sure? I thought that was just a problem particular to early encoders for the Vorbis codec, which were alleviated by altering the tuning parameters of the encoder.

I'm basing it purely on modern (Within the past couple of years) encoded 320kbps/V0 MP3s.

I have not done any personal blind ABX tests on AAC or modern ogg vorbis, so I can't really speak to them.

I'm going to keep 'archival' quality stuff in FLAC anyway, just so I'm covered for any advances in compression tech or whatever, and I stream to my mobile stuff, so size concerns aren't a huge deal for me. My ABX testing has just been for the sake of the mp3 vs FLAC argument.

So, AAC and Vorbis might have very well solved the problem of compressing some of these instruments.

Re: 24/192 music downloads are silly

#202

TL;DR, but skimming through an interesting problem comes to mind: The OP "orthogonalizes" the question of the sample accuracy's (24 vs 16 bit) and sample rate's (48 vs 192 kHz) impact on quality, answering one independent of the other. But even with my limited background in mathematics it's quite obvious that that approach is not entirely correct: the Nyqvist theorem only really applies when you have infinite sample…

The highest representable frequency really is the Nyquist rate: you only need 1 bit of sample depth to generate a digital signal whose corresponding band-limited continuous signal is a sine wave that oscillates at that rate.

Sample depth roughly tells you how far away a sample can be before the magnitude of the ideal sinc function used to reconstruct the continuous signal falls below your quantization threshold. That distance in turn gives you an idea of the frequency resolution you have... You could in theory run an FFT over that many samples and detect that the corresponding change was not just due to quantization noise.

Re: 24/192 music downloads are silly

#203
post #90
post #44

Earlier quoted context omitted.

Let's do the math. If I didn't screw it up (and I probably did), an 8k iphone 6 would be around 1600 dpi.

Imagine being able to use a physical magnifier to see more information on the screen. Wouldn't that be great? at least for a curious child?

so, carrying that to its logical conclusion, does that mean that at some point we will create displays w/ such a high resolution that they will, in some sense, be creating a "universe" which is indistinguishable from that which they are displaying? or, i guess that would mean the display essentially is what it is displaying. is that even possible in our universe, or would that be akin to creating energy / matter from nothingness?

clearly the display would blink "let there be light"* at startup.

* http://www.multivax.com/last_question.html

Re: 24/192 music downloads are silly

#204

Earlier quoted context omitted.

Bose and beats* are by, every /objective/ measure, shitty products. Subjectively, you might like them, but the faithfulness of audio reproduction is not a subjective matter. You can play a tone and measure how well that tone is actually played back. You can then also objectively compare things that produce that playback quality at various price points and figure out if they're priced competitively. There is plenty of…

Are Beats shitty or just expensive? How little would I have to pay to get same quality? I am finding it hard to believe that they are actually shitty, while I find it very easy to believe that they are way overpriced. I have never listened to Beats headphones but I imagine they have a lot of base-boost (based on absolutely nothing), but that is not the same as shitty.

So, we have to define, in your opinion, what would make a pair of headphones shitty.

If you are going to reduce them to the basest level of what the purpose for a speaker or headphone is, to reproduce the input sound, then yes, they are shitty, because they are not good at that.

From a purely objective standpoint, you are going to have to judge them based on that. Why would you want the speakers or headphones to make a different sound than what the signal is?

If you want to move away from an objective measurement of what makes a headphone good or not to something that's purely subjective (i.e. 'I like how they sound'), it's impossible to answer that question.

The Solo2 are a pair of Beats headphones that actually measure really well - they're good at the base purpose of a transducer. But they're $250. You could buy a pair of Sony MDR-7506 that measure similarly (IIRC, a bit better, even) for $85.

Re: 24/192 music downloads are silly

#205

Earlier quoted context omitted.

Bose and beats* are by, every /objective/ measure, shitty products. Subjectively, you might like them, but the faithfulness of audio reproduction is not a subjective matter. You can play a tone and measure how well that tone is actually played back. You can then also objectively compare things that produce that playback quality at various price points and figure out if they're priced competitively. There is plenty of…

Are Beats shitty or just expensive? How little would I have to pay to get same quality? I am finding it hard to believe that they are actually shitty, while I find it very easy to believe that they are way overpriced. I have never listened to Beats headphones but I imagine they have a lot of base-boost (based on absolutely nothing), but that is not the same as shitty.

Given whenever I stand near someone on a train with them I can hear a fair amount of their music (not anywhere near as bad as Apple earbuds though), I assume they can't be that great - that or the listener has very bad hearing.

I have a set of Sennheiser HD 202 which don't have anywhere near the same leakage and cost £35. I haven't tried Beats so can't say much about audio quality, but in my experience high leakage usually means that the audio is poor too. It also means you will listen to music louder to compensate, which leads to more distortion.

> I am finding it hard to believe that they are actually shitty

In that case the marketing team have done a good job :-)

Re: 24/192 music downloads are silly

#206
The author confuses sampling theory with reality.

Sampling theory says you can reconstruct a signal by sampling it at least twice per cycle. So 44.1KHz is an adequate sampling rate for an 22.05Khz signal.

Unfortunately to make Digital-to-Analog conversion work according to theory, you must first construct an ideal analog filter which filters out everything above 22.05Khz while leaving everything less than 22.05Khz unmolested. That's not possible in reality. If 20KHz is the goal, you have a measly 2.05KHz to make the filter ramp from kill-nothing to kill-everything. I'd imagine real-world CD players with cheap filters probably kill everything above 15Khz.

In reality you want a lot of headroom between half the sampling frequency and the actual max frequency you want to pass unmolested. Even 48KHz only grants you a 4Khz band in which to let the filter roll off.

Second, significant playback timing jitter can render the LSBs useless. At 44.1KHz with 16bit sampling, the max difference between a pair of samples of a 22.05KHz max-amplitude input is very roughly 2^15. What does that mean? If your jitter is more than 692ns [1] you have just lost an LSB.

Sure, 24/192 is serious and unnecessary overkill. The advantage is that it has lots of headroom. The disadvantage is that it takes more space. If you were designing a new format today in our era of large hard drives, why wouldn't you waste a bit of space?

This isn't gold-plated monstrous-cable properly-broken-in HDMI snake oil. The current format isn't perfect; an upgrade is a reasonable idea.

[1] 44.1KHz period is 22.6ms; one part in 2^15 of that is 692ns.

Re: 24/192 music downloads are silly

#207

Earlier quoted context omitted.

> Some people buy $500 wooden knobs to make their volume pots sound better. (or was that a hoax? i can't tell anymore) Some people buy small pyramids to elevate their cables off the floor, some people buy mats to put onto your CDs before putting the CD in a player ( http://dagogo.com/millenniums-m-cd-mat-carbon-cd-damper-revi... ), some people buy $1000+/meter digital interconnect cables ( http://www.theabsolutesound…

On the other side of their spectrum, I went "near" an audiophile shop test booth and I was sucked by clarity and density of the sound in the air (this was a drum solo track). Some audiophileness is good. I'll head back to my 40$ crappy mp3 player now.

I actually think you'll find many "audiophiles" enamored of the Sansa Clip Plus and Zip, which fall into that price range. Probably the most highly thought of MP3 players after the iPod classic 5.5.

Re: 24/192 music downloads are silly

#208

Earlier quoted context omitted.

Those are low-budget audiophile products, ie they are still marketed mainly to boost the ego of purchasers. There are three brands of headphones that pros use: Beyerdynamic (typically DT-100 or DT-770), Sennheiser (typically HD-5/650) and Sony (typically MDR-7506/9). Beyerdynamics have somewhat better isolation so they're more popular in music studios, Sonys are more comfortable when you have to wear them all day so…

What's different between the $80 7506 and $200 7509?

Slightly larger driver, slightly heavier, supposedly has a greatly-extended frequency range of 5Hz - 80 KHz vs 10hz - 20Khz in the 7506. Of course your typical D/A converter won't even render such low frequencies due to DC coupling, and if they were there you'd want to EQ them away pronto as they would eat all your headroom. While I continue to enjoy excellent high-frequency hearing even in my mid 40s (to my surprise), neither I nor anyone else needs a tweeter that goes to 80 KHz.

The MDR-7509 and its successors the 7910 and 7920 have a lower impedance than the 7506 (24 vs 63 ohms) so if you plug them into the same sound source the higher-numbered models will be a bit louder - and as we all know, 'louder = better' for most people. This plus the larger driver is somewhat helpful for DJs, who work in very loud environments, but that's a fast track to hearing damage.

http://en.wikipedia.org/wiki/Sony_MDR-V6

Why I like the 7506 so much: on film sets I give them to eople to listen in and they say 'is it on? I don't hear anything.' Then I turn the volume down or make a small noise next to the boom microphone and jaws drop. Plugged into a quality microphone like a Schoeps, which has a very flat frequency response, it's like there's nothing there. I always have two pairs now because if one gets damaged I can't deal with other brands at all.

Re: 24/192 music downloads are silly

#209

Earlier quoted context omitted.

Are Beats shitty or just expensive? How little would I have to pay to get same quality? I am finding it hard to believe that they are actually shitty, while I find it very easy to believe that they are way overpriced. I have never listened to Beats headphones but I imagine they have a lot of base-boost (based on absolutely nothing), but that is not the same as shitty.

Given whenever I stand near someone on a train with them I can hear a fair amount of their music (not anywhere near as bad as Apple earbuds though), I assume they can't be that great - that or the listener has very bad hearing. I have a set of Sennheiser HD 202 which don't have anywhere near the same leakage and cost £35. I haven't tried Beats so can't say much about audio quality, but in my experience high leakage u…

>Given whenever I stand near someone on a train with them I can hear a fair amount of their music (not anywhere near as bad as Apple earbuds though), I assume they can't be that great - that or the listener has very bad hearing.

This makes the mistaken assumption that isolation and good sound are related, which -- as open headphones and speakers can attest -- is not true. The goal of a speaker or headphone is to reproduce music faithfully. Unless you are familiar with the music's origin or it has real instruments who's sounds you can easily identify, it's impossible for most people to tell if the music is reproduced "faithfully". So there are a couple of general rules that most "audiophiles" will consider when dealing with volume:

1. Music played at louder volumes generally sounds better than that at lower volumes. You can hear more of what you are intended to hear.

2. Music often goes up and down in volume, so you want to hear the broadest range of volume.

3. The best listening devices both allow high volumes without clipping and low volumes with clarity.

The point is, just because you can hear it, doesn't mean they are bad headphones.

It also doesn't mean they are good headphones or that the people aren't inconsiderate. It simply means that "sound leakage" isn't really a decent criteria unless it's something that important to you.

Re: 24/192 music downloads are silly

#210

I once spent ~2 hours explaining all of this (well maybe not all of it) to a friend of mine who was studying sound design at the time. He didn't believe me. I even transcoded some 24/192 FLAC Pink Floyd I had lying around and made him do a double blind test to show him that he'd prefer the slightly louder song every time, even if the louder song was 192kbps vs the FLAC. He did. He still doesn't believe me. He still t…

I don't know about comparing digital to digital, but I know I can tell the difference between a 320kbs mp3 and a good quality LP record. Its in the treble. I guess any kind of digital just ruins that.
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