We swear by our UE BOOM blue tooth speaker. It's portable and the sound quality is amazing. This tiny thing gets loud! It's also water resistant so can withstand some splashing from our grown up cannon balls. My parents also use one when golfing. They have had theirs for a few years and it has really held up. Also the battery life is amazing. I am buying us a second one because we saw a call blue one with a wave pattern that is much cooler than our blue one. The range is great to. We'll leave our phone by our kitchen window and the speaker will still work outside about 50-60 feet away. We got ours on Amazon.

UE BOOM 2 Phantom Wireless Mobile Bluetooth Speaker (Waterproof and Shockproof) https://www.amazon.com/dp/B014M8ZO8S/ref=cm_sw_r_cp_api_vJyxzbS7HBX9K

I have the UE Boom 2, great speaker with excellent sound and pretty good battery. I mostly use it in my garage and it's held up well.

Ultimate Ears Boom 2 Phantom Wireless Mobile Bluetooth Speaker (Waterproof and Shockproof) https://www.amazon.com/dp/B014M8ZO8S/ref=cm_sw_r_cp_apa_L15MBb8THXCEQ