I recently bought a portable speaker maily for my work packing the grapes. During August I got help and I usually harvested 180 kg per day. But now there is no hurry to pick the grapes, so I work alone while listening to music. I plan to harvest about 100 kg each day, and there is one third of the grapes to harvest, maybe 1 ton. So it is going to take a while.
Twenty years ago, when first I came to Japan for a masters in Geology, I got my self a MD player and also portable speaker that I used during harvest until last year, and it still works. I threw away the MD player when we moved last year.
I am pretty happy with the sound for the cost of the speaker. I also have a free Spotify subscription and I can use both the ipod and my phone. Easyly go back in time, Domindo Dancing by Pet Shop Boys.