1-bit is out

Today I shipped 1-bit, an iOS music player for people who care how their music sounds.

Why “1-bit”? Because that’s the number that matters. DSD — Direct Stream Digital, the format behind SACD — encodes audio as a single-bit stream sampled millions of times a second, instead of the 16 or 24 bits per sample you get from PCM (think CDs, FLACs, most of Apple Music). It’s a different way of thinking about digital audio, and it’s what 1-bit is built around.

The name is also a promise. The app doesn’t resample, doesn’t remix, doesn’t touch your audio on the way to your DAC. What goes in comes out — bit for bit.

What it does

Point it at an SMB share on your home network — a Synology, a QNAP, a Mac running File Sharing, whatever you already have — and 1-bit scans your library, reads the tags, pulls the artwork, and builds a browseable catalog of your albums and artists. Plug in a USB DAC and hit play.

If you don’t run a NAS, drop files into the app’s Documents folder via Files or Finder over USB and it works the same way.

No accounts. No cloud. No streaming service. Your music, your network, your DAC.

Bit-exact, and what that actually means

For PCM, 1-bit sends samples straight from the file to the audio engine to your DAC, bypassing the iOS system mixer entirely. For DSD, it reads DSF files and packs the 1-bit stream into DoP (DSD over PCM) frames for the DAC to decode natively.

This matters most if you own something like a Chord Hugo 2, a Mojo 2, or one of the many USB DACs that can lock to a native DSD carrier. Those DACs sound their best when software gets out of the way. 1-bit gets out of the way.

It also handles the fiddly parts that trip up most iOS music apps:

• Sample-rate renegotiation when you jump from a 44.1 kHz FLAC to a DSD128 album
• PLL settling time on FPGA-based DACs (the Chord family needs roughly 700 ms to re-lock cleanly — Hugo 2 will go silent without it)
• Gapless playback when consecutive tracks share a format
• DoP marker-phase continuity across track transitions, so your DAC never flickers mid-album

Who it’s for

If you have a NAS full of FLACs and DSFs, a good DAC, and a pair of headphones or speakers you actually listen to — this is for you. It’s not trying to replace your streaming service. It’s trying to be the nicest possible way to listen to the music you already own.

1-bit is on the App Store now, for iPhone and iPad running iOS 18.6 or later.

Just press play.