What playing one sound through every speaker actually taught me

I built Tutti because macOS still only lets you play audio through one output at a time, and I was tired of picking between my desk speakers and my MacBook. The idea was simple — tick a few outputs, hear the same thing everywhere. Building it was less simple, and two problems in particular ended up reshaping the whole app.

The first was sync. The moment I sent audio to more than one device, they drifted apart. My MacBook were basically instant, but a Bluetooth speaker lagged just enough to sound like a faint echo across the room. Slowing everything down to match the laggiest device felt wrong. So instead I added per-device latency tuning — you nudge each output forward or back a few milliseconds until they all land together. Once it's dialed in, the whole room sounds like a single speaker.

The second one I didn't see coming: stereo. In headphones, left and right are obvious — the mix is made for two ears sitting right next to each other. But send that same track to two speakers across the room and each one just plays the full mix. The stereo image collapses into a kind of mono mush. So I added stereo L/R split: one speaker plays the left channel, the other plays the right. Two cheap speakers placed a few feet apart suddenly give you an actual soundstage.

Neither of these was on my original list. They came from just living with the thing and noticing what felt off.

Tutti's going live on Product Hunt today — built entirely on Apple frameworks, no virtual driver, no kernel extension, free to use. I'd love to hear what breaks for you, especially the weird corners of Bluetooth and AirPlay.