Tribit StormBox Micro 2

The budget pick for strapping to a bike or pack. The StormBox Micro 2 has a strap built into its back that cinches around handlebars or a shoulder strap, and at about 11 ounces it barely registers once it is on. It is IP67 sealed, rated for up to 12 hours, and its 4,700 mAh battery can give a phone an emergency top-up. The sound is small and light on bass, so think trail-side background music rather than a campsite party. It usually sells for around $60 or less.