Comment by seanp2k2 | Hacker News Reader

Comment by seanp2k2 | Hacker News Reader

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Same. It's crazy to me that people are saying that they can hear the difference between 24-bit 192khz recordings and something like 320Kbps MP3 or 192 VBR (which is what most of my personal collection is at). Back in the day on [huge;y famous private torrent tracker], FLAC and 192k VBR were the gold standards, with most opting for the VBR version. I personally have some VERY nice headphones, speakers, and sources (Senn HD800s, Westone ES60, KEF LS50, RME ADI-2 Pro, etc), and I can't hear the difference between this high-bitrate stuff and the lower encodes. I CAN hear a HUGE difference between bad recordings and good, but that doesn't stop me from enjoying my favorite albums. I have other headphones, speakers, IEMs, and sources for different needs, for example working out...I like my Jaybird Tarah Pros, and even though they're not "audiophile", I've still had tons of enjoyment with them doing things like skateboarding, mountain biking, and riding my motorcycle. Horses for courses. The HD800s is NOT great for bass-heavy music, so in that case, I'll switch to a Shure 1540 or Beyer DT1770, which even though they're more in the higher-end mid-fi range, have each brought me many hours of pleasure over the years.

This is a fun hobby, but it's possible to make it less fun by arguing on the internet with people about it. If it sounds good TO YOU, and it's worth the price TO YOU, then never let someone make you feel bad about it. Some people buy $10k cables (or "worse" imo, cable elevators [e.g. https://forum.audiogon.com/discussions/the-finest-cable-elev... ]. I think that those are ridiculous, but some people swear by them, and that's their choice. I'm the guy with the inner tube under the turntable playing with air pressure, because I love a good hack and have a penchant for DIY. I've built speakers that sound bad, but I've always learned something from every build. If you want TRUE REFERENCE sound, look up exactly what gear your favorite recording studio uses, and buy the same set-up. Otherwise, just have fun :)

I can hear the difference between them but honestly I listen to Spotify on highest quality setting (320Kbps I think?) for my everyday because it's convenient and already sounds great. I'm listening in an imperfect environment anyways with environmental noise from outside and a non-treated room. My main benchmark is does the codec give me listening fatigue which, for example, Soundcloud and 128Kbps does but 320Kbps doesn't.

As an aside people who swear by 24-bit audio don't even understand what bit rate does in context of audio. It's only useful in the studio context.

Edit: Not sure why I'm getting down voted. I can explain the difference as added sparkle in the transient high end frequencies. My hypothesis is that the presence of frequencies outside of the range of our ears affect the frequencies within our hearing range. It's pretty common to have to re-EQ the whole track after EQing one instrument in a mix so this concept is just being applied outside our hearing frequency spectrum Also I would like to point out that higher bandwidth audio doesn't necessarily sound better to me, just different.

I work in Film Postproduction and work as a soundesigner or re-recording mixer and also mix music from time to time.

In audio production you can really feel the difference between 16 bit Audio and 24 bit. Just like in photography were RAW only really makes a difference when you start to manipulate the data you really start to hear the difference between 16 and 24 bit once you work with recordings.

24 Bit allows more “shades” of loudness between the loidest signal and absolute silence. This means the above statements depend on the dynamic range of the recording, which is arguably too low in these days.

As an output format 16bit should be enough for most scenarios and except for a few edge cases hearing the difference of a well mastered 16bit recording to the same thing in 24 bit should be nearly impossible.

This however refers all to uncompressed audio. Depending on your audio gear you can definitly can hear a difference between uncompressed/lossless and lossy mp3 compression even at 320kbps. The same is true for 330kbps vs 128kbps mp3.

I must admit that I cannot differenciate between uncompressed and opus 256kbps.

If you do anything that needs audio compression I strongly recommend looking at the Opus Codec

I upvoted you, but you're wrong. 24bit audio depth matters, especially in jazz and classical recordings. You notice both subharmonics and superharmonics missing. Particularly when their phase is slow in time.

> Particularly when their phase is slow in time

What does this mean?

Compressors variably quantize a frequency band based on what is considered to be imperceptible to human ears. Imagine a standup bass is sustaining a note. That has a bunch of different resonances based on; strings, the wood of the bass, and the geometry of the room. In a live setting, those material properties create interference between the source of the sound and the reflection. But they're very quiet and can reverberate on the order of seconds. So most compressors will quantize the constructive/destructive dynamic range to the same value.

In rock music this doesn't matter so much. But orchestras may even use the room geometry as an effect.

> 24 bit audio depth matters,

Please forgive me but I'm not going to just accept someone's word on this when the science seems to point in the other direction.

Is there any properly conducted test that backs this up?

Case in point. The bit rate has to do with dynamic range not frequencies.

The reverberation of a single tone can be in phase or out of phase. The results is observed as a beat frequency in amplitude.. not in tonal frequency, that's what why bitrate matters.

We use higher bitrates during recording to lower the noise floor, in turn giving more headroom in the mix. Once you mix down this becomes irrelevant because the difference between silent and full volume at 16bit is enough to cover the full capability in terms of sound pressure levels of the human ear. 1bit = 6dB which means 16bit is 96dB. As we don't start at absolute zero but with a background noise of the room at 30dB using the full dynamic range of 16bit at playback you risk deafening yourself.

In your example if your single tone is out of phase then 1) how do you control this at any bit rate and 2) this is controlled by an acoustically treated room and a skilled engineer during recording. When you listen on headphones you already eliminate this concern on playback and unless you are listening in a professional designed and treated listening studio you will always have some element of phase cancellation. This is the listening character of your room and will occur at any bitrate.

Read this https://www.mojo-audio.com/blog/the-24bit-delusion/

You know - I agree with this article. Thank you for your thoughtful response.

I understand and agree that 24bits is enough for human perception. But something else is happening in MP3 encoding. Some sort of assumptions about human perception of dynamic range that are inaccurate. I am not expert enough to know precisely where. But I generally understand compression and I am an "audiophile".

Nothing in the article stands out as false to me. But I cannot help but believe it might be missing something.

> transient high end frequencies. My hypothesis is that the presence of frequencies outside of the range of our ears affect the frequencies within our hearing range

This is something I wonder about, too, but by my limited knowledge of signal processing the low pass effects of the signal transmission path do simply not admit any such frequencies. I wonder whether that counts for all orders of derivation, though.

I wonder if higher frequencies can cause resonance in lower frequencies, undertones instead of overtones so to speak, maybe in exotic geometries like the inner ear. Echo location famously works better in the ultrasonic range and involves higher order derivatives. We don't talk of constant sinusoids, but ultrasonic sweeps and chirps (not sparkle :D). We can't hear ultrasound, but perhaps we can sense it similarly to how we can sense lowest frequencies as rumble.

I really don't know the maths, what is a really low frequency note played for nanoseconds? High frequency Pulse Width Modulation is used to modulate sound in the audible range, which is quite tricky to get right mathematically and in hardware. The common problem is the introduction of ringing, indeed.

By the way, I really like to listen to music under the shower in the next room. I hear, or rather hallucinate, the most wonderful sounds under the noise.

There are always a few tell tale signs that audiophiles can pick out. In an analog mix, you should never expect two instruments to share a quantization... But that's what you hear with compression. The cymbal quantization is dependent on the guitar line and the tom/kick bleeds into the bass drum. The attack of the bass bleeds into the guitar, etc. If compressors had access to the raw channels, this is not so much a problem - you can keep each band stable. But they don't, they operate on the frequency domain of the entire mix.

yeah, for biking/skiing i use a-JAYS Five. for traveling 1MORE Quad Driver, for at-home audio Sennheiser HD 6XX and for gaming Klipsch ProMedia 2.1. the PC has an Asus Essence STX II 7.1 and onboard Realtek ALC1220 (surprisingly great, btw).

anyone who claims to hear a difference between 24-bit 192khz and a 320Kbps CBR MP3 is drinking some good kool-aid. there's a great quote by Alan Parsons:

"Audiophiles don't use their equipment to listen to your music. Audiophiles use your music to listen to their equipment."

I once went to an audiophile's place. He had one wall covered with equipment, paid tens of thousand of euros (actually liras, back in the day).

He had twenty records. Ten of them were test signals.

>It's crazy to me that people are saying that they can hear the difference between 24-bit 192khz recordings and something like 320Kbps MP3 or 192 VBR

With some decent headphones and a basic knowledge of compression artifacts, it's not particularly difficult to tell the difference in a blind test. You can diff a FLAC and MP3 recording using phase inversion, which allows you to train your ears to recognise compression artifacts. Modern perceptual encoders are very good, but they're not perfect. It's not a difference I particularly care about, but it is there.

> 24-bit 192khz

Chances are my soundblaster soundcard does not support either of those.

Similarly, you can't just diff two different recording of two different sample rates without conversion, so the conversion would either introduce artifacts if upsampling (and if it wouldn't, you wouldn't hear a difference) or render any advantage obsolete if downsampling the high sample rate. Obviously depends on the algorithm used, but you should target whatever your soundcard supports.

The 24/192 part is irrelevant - there's no audible difference between properly-mastered 16/44.1 and 24/192 audio. No adult human can hear anything above 22kHz; 16 bits provides 96dB of undithered dynamic range and ~120dB of perceived dynamic range with shaped dither.

You can hear the degradation from 16/44.1 bitstream to 320kbps or 192kbps VBR MP3, but you need good gear and good ears. I'm perfectly happy to listen to properly encoded MP3s because the difference is very slight, but I'd still use uncompressed or lossless formats for archival purposes.

> If you want TRUE REFERENCE sound, look up exactly what gear your favorite recording studio uses, and buy the same set-up. Otherwise, just have fun :)

It's interesting how much audiophiles focus and are ready to spend on gear when acoustic treatment (including planning and building) of the room brings undeniable and immediate impact, and in it's basic form can be orders of magnitude cheaper than all those insane RCA and power cables, supporters, pyramids and whatnot.

Just buying the same gear without proper acoustics won't bring you the "TRUE REFERENCE".

This. Just looking at a graph for resonances in a room, or moving around while playing a low-freq tone, is enough to give you an idea of the enormous difference a properly treated room would make.

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