Music Production File Formats: Stems, Bounces, and Masters Explained

If you've ever finished a track and then panicked about what files to send your mixing engineer or label, you're not alone. Music production has its own vocabulary around exports, and nobody explains it properly.

Let's fix that. This guide covers the three main types of exports you'll deal with — stems, bounces, and masters — plus the actual file formats you should use for each. No gatekeeping, just practical info.

What Are Stems?

Stems are individual tracks or groups of tracks exported separately. Instead of exporting your entire song as one stereo file, you export each instrument or element on its own.

Why would you do this? Because stems give whoever is mixing or remixing your track total control. They can adjust the volume of your vocal independently from the drums, tweak the EQ on the bass without affecting the synths, or completely replace elements.

Here's what a typical stem export might include:

• Lead vocals (dry, no effects if possible)
• Backing vocals
• Drums (sometimes split into kick, snare, hi-hats, etc.)
• Bass
• Synths or guitars
• Pads or atmospheric elements
• Effects and transitions

Each stem should be the full length of the song, starting from the same point (usually bar 1), even if that track doesn't come in until later. This ensures everything lines up perfectly when imported elsewhere.

File Format for Stems: WAV All the Way

For stems, you want WAV files at 24-bit / 44.1kHz (or whatever sample rate you produced in).

WAV is uncompressed, meaning no audio data is lost. It's also universally supported — every DAW on the planet can import WAV files without issues. Some producers prefer AIFF (Apple's equivalent), which is also fine, but WAV is more common.

Never — and I mean never — send stems as MP3 or AAC files. Those are lossy formats that throw away audio information to save file size. Once that data is gone, it's gone forever. Your mixing engineer will hate you.

If you need to save storage space, FLAC is an acceptable lossless alternative. But honestly? WAV is king. It's simple, reliable, and works everywhere without thinking about it.

Need to convert your stems to WAV from another format? Use KokoConvert's audio converter to ensure clean, uncompressed exports.

What Is a Bounce?

A bounce is just your full mix exported as a single stereo file. It's what you listen to outside your DAW to check how the song sounds on different speakers or in your car.

But here's where it gets specific: when you're sending a mix to a mastering engineer, they'll often ask for a "pre-master bounce" or "mix bounce." This means a version of your track with:

• No limiting or mastering plugins on the master channel
• Around -6dB of headroom (peak levels around -6dB, not hitting 0dB)
• All your mix decisions baked in (EQ, compression, effects)

The headroom is crucial. If your mix is already slammed to 0dB, the mastering engineer has nowhere to go. They need dynamic range to work with.

Bounce File Format: WAV 24-bit Again

Same as stems: WAV at 24-bit, matching your session sample rate (usually 44.1kHz or 48kHz).

Some people argue about 16-bit vs 24-bit for final mixes. Here's the deal: 24-bit gives you more dynamic range and precision during processing. Since storage is cheap now, just export at 24-bit. Your mastering engineer might downsample to 16-bit later for CD or streaming, but that's their job, not yours.

And look, if someone asks for a quick demo bounce to check on their phone? Sure, send an MP3. But for anything professional — mixing, mastering, archival — stick with WAV.

What Is a Master?

The master is the final, polished version of your track ready for distribution. It's been through mastering (loudness adjustment, final EQ, limiting) and is optimized for streaming platforms, radio, or physical media.

Masters usually come in a few versions:

• High-resolution master: 24-bit WAV, the archival version you keep forever
• Distribution master: 16-bit / 44.1kHz WAV for CD-quality streaming (Spotify, Apple Music, etc.)
• MP3 master: 320kbps CBR for platforms that require MP3 uploads

Different platforms have different requirements. Spotify prefers 16-bit / 44.1kHz WAV files, but also accepts FLAC and high-quality MP3. Bandcamp loves FLAC because fans appreciate lossless downloads.

The key is to keep your 24-bit master safe. That's your source of truth. Everything else is a derivative you can regenerate later if formats change (and they will).

Master File Formats: Depends on the Destination

Here's a quick reference for what to export:

• Archival master: WAV 24-bit / 44.1kHz or 48kHz (whichever you mastered at)
• Streaming (Spotify, Apple Music, Tidal): WAV 16-bit / 44.1kHz
• Bandcamp / Beatport: FLAC or WAV 16-bit / 44.1kHz
• SoundCloud (if you have Pro): WAV 16-bit, otherwise 320kbps MP3
• YouTube: WAV or high-quality MP3 (they re-encode anyway, but start with quality)
• CD duplication: WAV 16-bit / 44.1kHz (the Red Book standard)

If you need to generate multiple format versions from your master WAV, batch audio conversion tools save you a ton of time. Export once, convert to everything you need.

Sample Rates and Bit Depth: Does It Really Matter?

Short answer: mostly no, unless you're doing specialized audio work.

44.1kHz / 16-bit is CD quality. It's been the standard for decades because it works. Human hearing tops out around 20kHz, and 44.1kHz captures frequencies up to 22.05kHz (thanks, Nyquist theorem). 16-bit gives you 96dB of dynamic range, which is more than enough for music.

48kHz is common in video production and some streaming platforms. If you're scoring for film or TV, work at 48kHz from the start.

Higher rates (96kHz, 192kHz)? They give you ultrasonic frequencies that humans can't hear. Some engineers swear by them for recording and mixing because plugins allegedly sound better with extra headroom. But for final distribution? Total overkill. Spotify will downsample it to 44.1kHz anyway.

Same with 32-bit float. It's amazing during production because you literally can't clip. But for final exports? 24-bit is more than sufficient.

Practical Workflow: How to Organize Your Exports

Here's how I structure my export folders, and it's saved me countless headaches:

Project folder:

• /Stems — Individual WAV files for each track element
• /Mix-Bounces — Pre-master stereo mixes with headroom
• /Masters — Final mastered versions in multiple formats
• /Alternates — Instrumental versions, radio edits, stems for remix contests

Every file gets a clear name: Song-Title_Element_Version.wav. So you get things like Midnight-City_Vocals_v3.wav or Midnight-City_Master_16bit.wav.

This might seem overkill when you're working on one track. But six months later when a label asks for the vocal stem and you have 47 files named "bounce_final_FINAL_v2_ACTUAL.wav"? You'll thank yourself.

Common Mistakes to Avoid

Sending stems with effects baked in (unless specifically requested). The whole point of stems is flexibility. Export your vocal dry, then provide a separate "vocal FX" stem if you used heavy processing.

Exporting stems at different lengths. Every stem should be the same duration, from the same starting point. Silence is fine; misalignment is not.

Using MP3 for anything production-related. MP3 is for listening, not for working. Period.

Forgetting to include a reference mix. When you send stems, also include a rough mix of how YOU think it should sound. It gives the mixer or remixer a creative direction.

Not checking your exports. Always re-import your bounces and stems into a fresh project and make sure they sound right. Glitches happen. Better to catch them before you send files to someone else.

Final Thoughts

Music production file management is one of those things that seems boring until it bites you. But once you have a system — clear naming, organized folders, the right formats for the right purposes — it becomes second nature.

The core principles are simple: WAV for production work, appropriate bit depth and sample rate for your project, and always keep your high-res masters archived.

And when in doubt? WAV at 24-bit / 44.1kHz. You'll be fine 99% of the time.