Send music files at full quality: stems, sessions and masters

How big are music files?

Uncompressed audio size is simple arithmetic: sample rate × bit depth × channels. Per minute of audio:

A single 24-bit master already passes Gmail’s 25 MB limit. A multitrack session adds up fast: 48 mono tracks at 48 kHz/24-bit for a 4-minute song is about 1.7 GB of audio, before plugins, takes and bounces. An album’s worth of sessions easily reaches 20 to 50 GB.

Why not WhatsApp, email or a streaming link?

• Chat apps compress audio sent as voice notes or media. WhatsApp keeps the original only when you send the file as a document, up to 2 GB. See send audio on WhatsApp.
• Email stops at 20 to 35 MB depending on the provider.
• Streaming platforms re-encode what you upload, which is fine for listening and useless for mixing.
• A transfer link delivers the exact file, at any sample rate, and works for anyone.

How to send stems or a full session

1. 1

   Step 1

   Bounce or collect the session

   Export stems starting at bar 1 so they line up, or use your DAW’s save-as or collect option to gather all audio files into the project folder.

2. 2

   Step 2

   Name things clearly

   Song, tempo, key and sample rate in the folder name (for example “Night Drive 122bpm Am 48k”) saves a round of questions.

3. 3

   Step 3

   Upload the folder

   Drag it onto transfr.me. Folders stay intact, up to 100 GB per transfer on the free plan.

4. 4

   Step 4

   Set the link

   Expiry of 1 to 7 days, a password for unreleased material, a custom link such as transfr.me/nightdrive-stems.

5. 5

   Step 5

   Send it

   By email to up to 10 people (the mixer, the producer, the label contact) or paste the link anywhere.

Listening before downloading

On the download page, audio files can be played in the browser, so a label contact or a client can listen to the demo or the mix before pulling gigabytes of stems. Formats the browser supports (MP3, WAV, AAC and usually FLAC) play directly; others download normally. A good habit: include a stereo bounce or an MP3 reference mix alongside the stems.

Sending demos and masters

On Pro, Send & Track shows whether a recipient opened the page, played the preview and downloaded each file, which tells you when a follow-up email makes sense. See download tracking.

Receiving files from collaborators

Remote sessions mean files coming back from a guitarist in Lisbon, a vocalist in Montreal and a drummer down the road. Share one file request link: each person uploads up to 100 GB without an account, you get an email when files arrive, and you can set a deadline for the takes. Submitted files stay for 7 days, so move them into your project folder when they land.

Ideas recorded on your phone

Song ideas often start as a voice memo or a phone video at rehearsal. Messaging apps squeeze those recordings, which matters when the producer wants to sample the vocal. Open transfr.me in the phone’s browser, add the memo from Files (iPhone voice memos can be shared or saved there) or from your recordings folder on Android, and text the link. The file arrives as recorded, in its original format, ready to drop into a session. See send large files from iPhone.

For studios and producers: your name on the page

If you deliver mixes to paying artists, Pro puts your studio’s logo and a background image or short video on every download page, on your own subdomain or domain. Links last up to 60 days, which suits artists who take their time with approvals, and transfers have no size limit, which suits full album sessions. A team of up to 10 people (engineers, assistants) shares the same brand and a common space.

Keeping unreleased music private

Leaks usually come from links that live too long or travel too far. Use a password shared by text, a short expiry and a download limit of 1 for advance copies. For the most sensitive material, end-to-end encryption encrypts the files in your browser before upload; the key lives in the link and is never stored on our servers. More in secure file transfer.

For general advice on audio formats and sizes, see send large audio files. If you also deliver music videos, our videographers page covers video workflows.

Start with the next set of stems you owe someone: one folder, one link, a reference mix on top. If your collaborator can play the mix in the browser and pull the stems in one go, you will not go back to splitting files.