Share Music Files Online: Send Audio in Lossless Quality

To share music online without quality loss, send the actual file — not a stream. WAV, FLAC, ALAC, and AIFF are lossless containers; MP3, AAC, and Opus are lossy. Streaming services (Spotify, Apple Music, Bandcamp) re-encode everything on upload, which defeats the point of delivering to a collaborator, mastering engineer, or sync-licensing client. A browser-based file transfer preserves every byte. Upload the 24-bit/96 kHz WAV mix, share the link, recipient downloads the same bits that left your DAW.

Lossless vs lossy: what's actually in the file

A WAV file at 24-bit/48 kHz stereo holds roughly 16.5 MB per minute — uncompressed PCM in an RIFF container (RFC-ish, Microsoft spec from 1991). No metadata compression, no audio compression, bit-perfect.

FLAC (Free Lossless Audio Codec) gives bit-perfect reconstruction at roughly 50–60% of WAV size by using linear prediction and Rice coding. A 24-bit/48 kHz FLAC of a 4-minute song lands around 40 MB vs 60 MB for the WAV. Decoded, the samples are identical to the source.

ALAC (Apple Lossless) is Apple's equivalent — similar compression ratio, native support in iTunes/Music and QuickTime.

AIFF is Apple's uncompressed equivalent to WAV, used by Logic Pro and Pro Tools.

MP3 at 320 kbps CBR is lossy — perceptual coding throws away frequencies masked by others. Re-encoding or bouncing through MP3 twice compounds damage ("transcoding loss").

Opus is a modern low-bitrate codec (RFC 6716) — great for podcasts at 64 kbps, inappropriate for mastering delivery.

For any professional audio workflow, the hand-off is WAV or FLAC. Never MP3.

Why streaming and messenger apps destroy quality

| Channel | What happens to the audio | | --- | --- | | WhatsApp | Re-encoded to Opus ~64 kbps | | iMessage | Converted to AAC or M4A at 64 kbps for voice notes | | SoundCloud free | 128 kbps MP3 transcode | | Dropbox preview player | Plays original file, but some clients cache reduced versions | | Gmail attachment | Preserves file (under 25 MB cap) | | Direct file download | Bit-perfect |

If you export a .wav from Ableton and send it through WhatsApp, the recipient hears an Opus 64 kbps approximation. An A/B test against the original reveals compression artefacts in cymbals, sibilance, and reverb tails instantly.

Typical music file sizes you'll be sending

| File | Size | | --- | --- | | Single track, 24-bit/48 kHz WAV, 4 min | ~66 MB | | Single track, 24-bit/96 kHz WAV, 4 min | ~132 MB | | Single track, 24-bit/48 kHz FLAC, 4 min | ~40 MB | | Full album, 12 tracks, 24/48 WAV | ~800 MB | | Stems (drums, bass, guitars, keys, vox × 4), 24/48 WAV | ~500 MB – 2 GB per song | | DAW session folder (Logic Pro .logicx) with audio files | 2–20 GB | | Mastering delivery pack (WAV + stems + session + notes) | 3–15 GB |

The stems bundle is where email and Slack fall down hardest.

Who needs the original file format

• Mastering engineers: require 24-bit WAV or AIFF at the session sample rate. MP3 is a hard no — many mastering studios (Sterling Sound, Abbey Road Mastering, The Exchange) explicitly reject MP3 submissions.
• Sync licensing agents: need WAV for broadcast-ready delivery (EBU R128 loudness, -23 LUFS for EU television, -24 LKFS for US TV per ATSC A/85).
• Film/TV composers: stems delivered at 24-bit/48 kHz WAV, BWF (Broadcast Wave Format) preferred because it embeds timecode.
• Remix artists: need stems at matching tempo/key, usually FLAC or WAV with metadata.txt describing BPM, key, and cue points.
• Mix engineers (returning to the artist): WAV print of the final stereo mix plus alt mixes (instrumental, a cappella, TV mix without lead vocal).

A clean delivery structure

Artist_SongTitle_v4_2026-03-18.zip
├── WAV_24-48/
│   ├── SongTitle_Master_v4.wav
│   ├── SongTitle_Instrumental_v4.wav
│   └── SongTitle_Acapella_v4.wav
├── Stems_24-48/
│   ├── 01_Drums.wav
│   ├── 02_Bass.wav
│   ├── 03_Guitars.wav
│   ├── 04_Keys.wav
│   └── 05_Vocals.wav
├── MP3_320/
│   └── SongTitle_Master_v4.mp3 (reference only)
└── README.txt

The MP3 in MP3_320/ is a reference copy — marked as such, so the mastering engineer doesn't accidentally treat it as the source.

Format-specific gotchas

• Pro Tools sessions: include the Audio Files folder and Fade Files folder, not just the .ptx. Without them, the session opens empty.
• Logic Pro: use File → Project Settings → Assets → "Copy audio files" before bouncing, otherwise the recipient opens a session with missing samples.
• Ableton Live: export a Project (not just the .als), which bundles samples, samples used in Simpler/Sampler, and automation.
• Cubase/Nuendo: "Back Up Project" consolidates and optionally removes unused media.
• Sample libraries (Kontakt, Omnisphere): don't include the library files — the recipient needs their own licensed copy. Just send the project file.

Encryption for unreleased masters

An unreleased single is worth money. A leak before release damages chart strategy and streaming playlists. Client-side encryption — AES-256-GCM with a PBKDF2-derived key — keeps the file unreadable on the transfer service's servers. The mastering engineer types the password in their browser, downloads, and the file decrypts locally.

HexaTransfer does this in-browser using the Web Crypto API. The password goes over Signal or a phone call; the link goes over email. The transfer service never holds the key.

Loudness and delivery compliance

If the destination is a streaming platform (Spotify, Apple Music, Tidal, Amazon Music HD), target loudness matters:

• Spotify: -14 LUFS integrated (normalised for playback)
• Apple Music: -16 LUFS integrated (sound check)
• Tidal: -14 LUFS integrated
• Broadcast (EU): -23 LUFS per EBU R128
• Broadcast (US): -24 LKFS per ATSC A/85

The mix delivery should honour whichever target applies; a mastering engineer adjusts final loudness depending on the destination. Send the file at -6 dB TP (true peak) headroom for mastering, so the engineer has room to work.

Service comparison for lossless audio delivery

| Service | Max size (free) | Preserves bit-perfect | Password | Expiry | | --- | --- | --- | --- | --- | | WeTransfer Free | 2 GB | Yes | No | 7 days | | SwissTransfer | 50 GB | Yes | Yes | 1–30 days | | Dropbox link | 15 GB quota | Yes | Pro only | Manual | | Google Drive link | 15 GB quota | Yes | No | Manual | | SoundCloud private | 5 hours audio | No (transcodes) | Link | Indefinite | | HexaTransfer | 10 GB | Yes (with E2E encryption) | Yes | Configurable |

Streaming is for listeners. File transfer is for collaborators.

Try it at hexatransfer.com — free, no account, 10 GB max.