Convert WAV to BCSTM online for 3DS music mods and themes, with WAV loop points kept. Upload files up to 20GB and download the converted result in a few clicks.
Convert BCSTM to WAVDrag & Drop your WAV file here
WAV files, up to 20GB
Files stay private.
Automatically deleted after 24 hours.
Link
20GB upload limit.
4.8/5
Trusted for 1,827,796+ conversions
HOW IT WORKS
Three steps, no account, nothing to install.
01
Upload your WAV file
Drag and drop a .wav file or select it from your device. For a looping BCSTM, save loop points in the WAV's smpl chunk with Wavosaur, Awave or a sampler editor first.
02
Convert to BCSTM
Keep BCSTM as the output format and start. The audio is encoded as 4-bit DSP-ADPCM, about 400 kbps for 44.1 kHz stereo.
03
Download the BCSTM
Download one .bcstm file per WAV and play it in vgmstream or a player built on it.
WAV
WAV is a RIFF-based audio format commonly used for uncompressed PCM audio. Audio editors, recorders and game audio tools such as vgmstream save WAV files, and loop editors such as Wavosaur store loop points in its smpl chunk.
BCSTM
BCSTM is the NintendoWare music stream format (CSTM) of Nintendo 3DS games, also used for the background music of 3DS HOME Menu themes. It usually holds 4-bit DSP-ADPCM audio, can store a loop and can group channels into tracks. 3DS modders and vgmstream-based players use it.
FILE FORMATS
SOURCE
Microsoft and IBM defined WAV in 1991. It normally stores plain PCM audio with no compression, which is why editors, DAWs, broadcast systems and speech tools accept it without question. The price is size: CD-quality stereo takes about 10 MB per minute, and tagging support is limited.
TARGET
BCSTM is the music stream format of Nintendo 3DS games and themes. Most use Nintendo's DSP-ADPCM codec at about a quarter of PCM size, some use PCM16, and many hold several stereo tracks the game mixes live. Loop points make the music repeat without a gap, often at the 3DS-native rate of 32728 Hz.
| Feature | WAV | BCSTM |
|---|---|---|
| Developed by | Microsoft and IBM | Nintendo |
| File extension | .wav | .bcstm |
| Compression | None (PCM) | DSP-ADPCM or PCM |
| Size vs uncompressed WAV | Same size (1:1) | About 1/4 (ADPCM) |
| Tags and cover art | Basic text tags, no cover art | Loop points, no tags |
| Best for | Editing, mastering, speech tools | 3DS game music and themes |
| Plays on phones and browsers | Yes | No, needs vgmstream |
USE CASES
Practical workflows where WAV to BCSTM conversion is useful.
Replace music in a 3DS game mod
Modders swapping a 3DS game's background music, for example through LayeredFS, can make a looping BCSTM from a WAV with smpl loop points.
Keep a mono sound mono
A mono WAV, such as an ambience bed or a voice clip, becomes a one-channel BCSTM instead of being doubled to stereo.
Re-loop an extracted song
Move the loop points of a song in a loop editor, then convert. The BCSTM loops at the new points, with the loop start moved to the next DSP block, at most 14,336 samples later (about 0.3 s at 48 kHz, 0.45 s at 32 kHz).
Rebuild an edited multi-track stream
A multi-track WAV saved by vgmstream keeps every channel, with one stereo track per pair, so a 4-channel stream becomes a 2-track BCSTM again after editing.
Reuse a Wii song in a 3DS mod
Decode a Wii BRSTM with our BRSTM-to-WAV tool and convert the WAV to BCSTM. Multi-track songs keep their tracks. Add loop points in a loop editor first if the song should repeat.
Mix a surround track down to stereo
A 5.1 or 7.1 WAV with a speaker layout is mixed down to a stereo BCSTM, so a surround export works without a separate stereo mix.
Convert a 96 kHz master
WAVs above 48 kHz become 48 kHz BCSTMs, so a high-resolution master converts without a separate resampling step.
Add music to a 3DS homebrew app
Homebrew developers can make looping or one-shot BCSTM streams from their own WAV music.
Make BCSTM test files for tools
Authors of BCSTM players and modding tools can make little-endian CSTM test streams from WAVs: mono, stereo, looping or multi-track.
Use sounds from an old sample library
A-law, IMA ADPCM and Microsoft ADPCM WAVs, 32-bit and float WAVs, and Broadcast WAV or RF64 files convert directly, without a separate conversion to 16-bit PCM first.
SUPPORTED FILES
Most kinds of WAV are supported, including looped ones.
Loops in a smpl chunk, as Wavosaur and Awave write them, are kept.
Every channel is kept for multi-track streams.
8 to 32-bit PCM, float, A-law, IMA and Microsoft ADPCM.
Large and broadcast WAVs work.
Converted, keeping the MP3's start delay and end padding.
Only convert audio you own or have permission to use. Having a file doesn't automatically give you the right to put it into someone else's game.
TROUBLESHOOTING
Most problems come down to settings the game expects, not the conversion itself.
01
The loop start moves forward to the next DSP block, at most about 0.3 seconds at 44.1 or 48 kHz, while the loop length stays the same.
02
Add loop points to a smpl chunk in Wavosaur or Awave before converting.
03
The game probably expects a different sample rate. Check an original file from the game and match its rate before converting.
04
3DS themes have size limits. Shorten the track or lower its sample rate.
05
Compare your track's loudness with the game's other audio and adjust it before converting.
06
Make sure the new file uses the exact name and folder of the one it replaces, then test it in the actual game or build.
VGAudio, LoopingAudioConverter and BrawlCrate encode Nintendo and CRI formats once installed. dragdropdo runs VGAudio in the browser, so you can turn WAV into BCSTM on any device.
| What matters | dragdropdo | VGAudio and Desktop Tools |
|---|---|---|
| Nothing to install | ✓Yes. Runs in any modern browser. | ~Yes. Windows tools or the .NET command line. |
| Works on phones and tablets | ✓Yes. Desktop, Android, iPhone and iPad. | ~No. Desktop only. |
| Batch conversion | ✓Yes. Add many files and download one ZIP. | ~Yes, with LoopingAudioConverter or scripts. |
| Share finished files | ✓Yes. Send a unique link from the result page. | ~You upload and share the files yourself. |
| Pricing | ✓Free with daily limits. $2.99 or $6.99 passes for unlimited use, no monthly plan. | ~Free. |
| Setting loop points | ✓Read from a WAV's smpl chunk. MP3 sources play once. | ~Yes. Most let you type loop points directly. |
Other tools use different pricing, limits and workflows. This comparison describes dragdropdo's own features without assuming every other tool works the same way.
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WHY DRAGDROPDO
Convert WAV to BCSTM in your browser, with nothing to install and nothing kept after 24 hours.
Private by default
Files are encrypted in transit and deleted from our servers automatically after 24 hours.
No install required
Convert in any modern browser on Windows, Mac, Linux, Android, iPhone or iPad. No app and no sign-up wall.
Big files and batches
Upload files up to 20GB each, add several at once, and download the results one by one or as a ZIP.
Share & download
Save finished files to your device or pass them on with a share link from the result page.
MORE WAV TOOLS
WAV (Waveform Audio File Format) is a standard audio file format used for storing waveform data. It delivers high-quality audio and is widely used in professional environments for music production and sound design. With its uncompressed format, WAV files ensure top fidelity, making them ideal for editing and mastering. Perfect for audio enthusiasts and professionals alike, WAV files guarantee an exceptional listening experience.
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FAQ
Answers to common questions about dragdropdo's WAV to BCSTM converter.
