Grimes above, Beat Connection below; photos by Bettina Hansen / Seattle Times

Saturday was the day for musical discoveries at Capitol Hill Block Party.

Festival owner Jason Lajeunesse discovered Grimes had way too much bass for the main stage, for instance. When the pixie-ish Canadian singer/producer couldn't hear her own music through the small monitor speakers facing her — which bounced into the air with each bass note — Lajeunesse ran on stage and duct-taped them to the floor.

She didn't miss a beat, bopping like a Muppet and mugging for the front-row photographers, embodying her stylish, unserious jams.

About a thousand people crammed together to watch her, making Pike Street a wonderful sea of bodies in motion or nightmare of jostling, depending how you saw it. The crowd sang the la-la-las to "Oblivion," Grimes' fluffy, delightful, underground dance hit, and the music sounded great, just a few machines and a microphone, no clutter, the sound split into extreme treble and bass with the constant noise of people talking/yelling in the middle.

Earlier in the day on the main stage, Seattle discovered the college-party vibe of Beat Connection — and longtime fans of the University of Washington group discovered its new incarnation.

Formerly a duo of deejays/producers Reed Juenger and Jordan Koplowitz, Beat Connection has swollen into a band, led by singer/guitarist Tom Eddy, backed by a horn section. The old Beat Connection threw dance parties. The new Beat Connection plays rock concerts with electronic flavor, and sings about things that happen at music festivals, like making friends whose names you can't remember. The transformation was most striking when Juenger and Koplowitz sang back-up for Eddy, as if it were his group all along. And maybe it was: the best song was the cooling "Silver Screen," one of Beat Connection's oldest, the first in their career to feature Eddy's vocals, two years ago.

Later in the evening at the nightclub Neumos, one Block Partier said to another, "I'm really glad we saw that."

They had been watching Yuna, the rising Malaysian singer-songwriter which neither of them had heard of before, prevail in a tough environment. Her breezy pop/R&B was quiet and the crowd was chatty, drowning her out if you stood in the back of the room. But up close it was a different story, an acoustic guitar concert that got bolder when Yuna stood up and sang while moving her hands in graceful waves, as if feeling the air from a car window on the freeway.

She meant for the pulsing "Live Your Life" to be the finale — a hit-in-waiting produced by American hip-hop superstar Pharrell Williams — but the audience cheered for an encore and she obliged, seeming grateful that amid all the racket, people were actually listening.

Other notable music discoveries Saturday: South African rapper Spoek Mathambo, who is signed to local label Sub Pop but does not come to Seattle often, and local band Stephanie, whose guitar lines sounded like synthesizers; review here.

Yuna; photo by me