New to digital audio? Start here

Digital sound is a list of numbers. The first lesson shows how WAV, FLAC and MP3 each store that list, with real file sizes, and which one to use. The next three follow the numbers from the disc to your speakers.

Read in this order

Check your own setup

Start with the file formats Ironbark, our music player

Learn

Files and playback first, then discs and tapes.

WAV, FLAC and MP3 →WAV writes every measurement down as-is. FLAC stores the same measurements in about half the space, with nothing lost. MP3 keeps only what you’re likely to hear. Computer to speakers →Getting music from a Windows PC to your amp untouched, the traps we hit along the way, and a ten-minute check for your own setup. Why 24-bit can play as 16-bit →A 24-bit FLAC can lose its lowest 8 bits on the way to your speakers, and Windows won’t tell you. Every place the bits can go, and how to check. All about codecs →How video and sound are squeezed into a file, the audio codecs you’ll meet, and why a file plays on one device and not another. How a CD stores data →A five-kilometre spiral of microscopic bumps, read by a laser, and error-correcting maths clever enough that a fingerprint doesn’t matter. Copy-protected CDs →Some CDs have wrong samples pressed into them on purpose. Why a copy of one can be neither exact nor verified, with diagrams. Cassettes to digital, yourself →A USB cassette player, Audacity and the one setting that matters most: the input level. How to record a tape without clipping it. HDMI ARC and eARC →How one HDMI cable sends a TV’s sound back to a soundbar, and what eARC adds for lossless surround and Atmos.

Tools

Our own music player, and things to listen to.

Ironbark →Our free, open-source music player for Windows, Mac and Linux. It checks every song plays bit-perfect and tells you if a “hi-res” file is real. No ads, no accounts. Free online music player →Ironbark in your browser: play the music files on your computer with no ads, no sign-up and nothing uploaded. Why we built Ironbark →The music player we built with AI in three weeks and gave away, and what “forever software” means for a small business. Music to discover →Newer artists we think more people should hear, sorted by genre. Not the classics everyone already knows. Reel-to-reel screen →A vintage reel-to-reel deck playing live jazz: turning reels, moving tape and VU meters that follow the music. Jazz generator →A small jazz band that makes up its music as it plays, never the same tune twice. ASMR generator →Trigger sounds made live in your browser. Mix them and move them from ear to ear in 3D.

The gear we use

Only what we use ourselves. Each one links to our write-up, where you can see what we measured and what to know before you buy.

DSD TECH SH-AU02A USB sound card

A small USB card with optical and coaxial digital outputs. We use it to send music from a Windows PC to our AV receiver over a coaxial cable, and to test Ironbark’s bit-perfect mode. It has no volume control of its own, so you set the level on your amplifier.

What we measured The 24-bit trap we hit

ELASO USB cassette player

The player we capture audio cassettes with. One USB lead carries the sound to the computer and powers the player. It’s a basic portable player, without Dolby noise reduction, so a good hi-fi deck will get more from a tape.

How we use it What it won’t give you

There are no paid links in this block. The lessons it points to include Amazon links, each marked “(paid link)”.

Rather have it done for you?

Our media transfer service →In Sydney, we digitise audio cassettes and standard VHS tapes, and copy CDs, DVDs and Blu-rays to an external drive or USB.

Audio: music files, CDs and getting good sound