[Casanova]

Audiophile Basics:

Sound behaves like a wave! 9th Class NCERT.

Resolution: It is measured in bits. For a CD, each sample has a resolution of 16 bits; its dynamic range is expressed over a range of 96 dB (decibels), with 1 bit corresponding to 6 dB.

Bit Depth: It determines the number of possible amplitude values we can record for each sample. The most common audio bit depths are 16-bit, 24-bit, and 32-bit.

• 16-bit: 65,536 values
• 24-bit: 16,777,216 values

So increasing the bit depth will give lesser noise and better sound signal and will be of higher file size. See the pic for better idea.

Dynamic Range: It is the ratio of the loudest sound to the quietest sound, expressed in decibels (dB). For Eg:

• 16 Bit: 96.33 dB (Not audible at normal listening level)
• 24 Bit: 144.49 dB (Unnecessary)

Humans can hear sounds between 0 and 140 dB. But sounds above 85 dB are harmful! For your curiosity:

• 60 dB - Audible - Sound of human voice
• 70 dB - Irritating - Television set on loud
• 100 dB - Extremely unpleasant - fighter jet

Sampling rate: It corresponds to the number of samples per second. For a CD, the sampling rate used is 44.1 kHz, meaning that each second of sound, when converted, is divided into 44,100 samples. This affects the precision with which the sound is reproduced: the higher the sampling rate, the more natural and precise the sound reproduction will be.

Humans can detect sounds in a frequency range from about 20 Hz to 20 kHz. (Human infants can actually hear frequencies slightly higher than 20 kHz, but lose some high-frequency sensitivity as they mature; the upper limit in average adults is often closer to 15–17 kHz.)

Now you might question if humans can only hear upto 20kHz, then why we use CD with 44.1kHz?

The Nyquist–Shannon sampling theorem says the sampling frequency must be greater than twice the maximum frequency one wishes to reproduce. Since human hearing range is roughly 20 Hz to 20,000 Hz, the sampling rate had to be greater than 40 kHz.

The Bitrate: Basically the flow of binary data, expresses the speed of information per second. It is measured in bits per second and is calculated fairly easily.
For CDs: 44,100 samples per second, each one sampled over 16 bits, everything over two channels (left-right stereo). We therefore get a bitrate equal to 44,100 x 16 x 2 = 1,411 kb/s: the bitrate of a CD is equal to 1.411 Mb/s. Immediately it’s clear that there is a massive difference between a CD’s bitrate of 1.411 Mb/s and an MP3 encoded at 320 Kb/s.

Lossy vs Lossless

Lossy: These compression formats (like MP3, AAC, etc) delete data that your ears can’t perceive in order to make files easier to transfer over the internet. Quality reduces, I have noticed. Significant reduction in file size. (3 min 6-10MB appx.)

Lossless: Lossless audio presents all of the information to you that was in the original uncompressed files. File size will be higher as its loss less. (3 min 30-50MB appx)

Factors on which the quality of music depends:

• Composition: It can refer to an original piece or work of music, either vocal or instrumental, the structure of a musical piece or to the process of creating or writing a new piece of music.
• Recording: It is basically physical record of a musical performance that can be played back, or reproduced. (In simple words singers will sing and their voice will be recorded, so better recording more realistic experience)
• Mixing: It is the process of taking recorded tracks and blending them together. Mixing is the step where different effects like compression, equaliziation, reverb, echo are added which will effectively define the sound and identity of the song and/or album.
• Mastering: It is a form of audio post production. It is the process of preparing and transferring recorded audio from a source containing the final mix to a data storage device (the master), the source from which all copies will be produced.
• Audio Source: Eg. Mp3, FLAC
• Your Device: What type of headphones or system you use. Generally Cheaper ones will give cheaper quality and Premium ones will be pricy but will provide better listening experience.

NOTE: Bluetooth is a wireless communication exchange standard between two devices. To read audio files, Bluetooth uses various codecs which reduce the quality of transmitted files.

Why Listening in Hi-Res is Useless? IMHO

A 2007 paper by Brad E. Mayer and David R. Moran described a double-blind trial where audio engineers, "dedicated audiophiles", and audio-recording university students were played CD-quality audio and self-described High-Resolution Audio.

The result? No perceptible difference between CD-quality audio and High-Resolution Audio.

Why is that?

• Humans can detect sounds in a frequency range from about 20 Hz to 20 kHz (for music production 44.1khz needed), but hi res usually comes in 48kHz to 192kHz, so you just filling your storage and paying more for similar experience.
• It comes to know that Hi-res have about 50% lesser noise as compared to 16 bit CD, but can you notice it? Do u really have that hardware or its just the Music Industries way to fit placebo effect in the minds of people and extract money?
• 16 Bit: 96.33 dB, 24 Bit: 144.49 dB, but pleasant decibels would be around 50 to at max 70 although 70 dB sounds irritating. So, no point in 24 bit hi res again.

Take a Test on you own.

Download 16 bit/44.1kHz and 24 bit/48-192kHz same Music ofc, use same volume levels, same headphones. Try to listen on interval of lets say 15-30 secs due to fatigue, then share your results here if you really can notice the difference.