
soundcore
Boom 2
Loud, bassy beast; needs EQ, no aux.

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My two Beosound A1 2nd gen were $130.96 & $145 used in 2022. $295.28 for two (including tax & shipping, on Amazon) - Strangely now $234 used on Amazon. If it drops to $131-145 again, great clean sound (not for bass-lovers). 3rd gen has better bass, but $399 list price.
Best sound quality I’ve heard is the Bang & Olufsen A1 (3rd Gen). Pricey, but great little speaker when you use their app to adjust your preferred sound/EQ.
Since you say price is not important... I have two B&O A1 Gen 2. They are very nice. Amazing sound, considering the size, as long as you are good with moderate volumes and fiddle a little with the EQ. Even better if you can stand it up against a wall or in a corner. Great battery life and small. Waterproof. Buttons for volume/next/back/pause, but not big and easy to use. Amazing for phone calls. I especially like my A1 for audiobooks, since they have nice EQ that can be used to enhance voice reproduction. I use my B&O A5 for loud portable music. And my AudioPro/WiiM multiroom setup for stationary music. Two are fun for stereo. I mostly use one as a bedside speaker and the other as a portable speaker. B&O A1 Gen 3 is out. A1 Gen 3 is said to be even better than A1 Gen 2. More bass. Longer battery life. If I didn't have my Gen 2 I would get one. At least one. [https://www.bang-olufsen.com/en/int/speakers/beosound-a1](https://www.bang-olufsen.com/en/int/speakers/beosound-a1)
What I use... For audiobooks I have found my B&O A1 unbeatable. Portable and great sound for speech. Also great as a phone speaker. I have one next to my bed. Not very loud, but great full sound otherwise, without annoying booming that can make voice reproduction tiresome. For loud stationary multiroom music I use my combo AudioPro/WiiM setup. AudioPro C20mk2 & C5mk2 and two UE Hyperboom with WiiM Mini optical hookup. The Hyperboom are great for outdoor garden party use. For portable music I like my B&O A1, especially fun in stereo, but they are not very loud outdoors. Then my B&O A5 is better.
I have two old UE Hyperboom. Amazing for larger social gatherings. Loud, if needed. But some effort to setup. I have a B&O A5. Great for the balcony or the patio. Easy to carry around and setup. Or I use a B&O A1 for some low volume ambience or to play an audiobook. I don't have a pool. But I don't think I would hear much swimming? When I do work in the garden I typically use active hearing protection, a 3M Peltor headset or use in-ear noise canceling headphones.
I think most BT speakers work like that when connected to power. If not connected to power I think most (=all) turn off automatically after a few minutes. My AudioPro C5, C20 works like this. Also my B&O A5 and A1. As do my UE Hyperbooms.
If it is for actual stationary use the AudioPro C20 is very powerful and great can also be used in a wifi multiroom setup. The C5 is nice and like the C20 have a sub out for extra oomph. The B&O A5 is amazing and somewhat portable, but very expensive. The A1 is great for a small room or having nearby. I have one next to my bed for sleeping-pill audio books. The UE Hyperbooms are also somewhat portable and also rugged as party-speakers indoors and outdoors, but a bit old and large now. If lucky you may find some second hand. I have upgraded mine with WiiM Minis. So they work in a multiroom setup with my AudioPro speakers. Also the AudioPro speakers I have are a bit old, new "W" versions were recently released, so you may find some second hand as well. The old version I have works with WiiM multiroom system. The new versions don't... I can recommend them all. I don't keep BT speakers I don't like... My favorite for large room use is the B&O A5. For audiobooks in a small room or nearby, the A1. The C20 is great for a big room, as are the Hyperbooms. I have the C5 in my kitchen. For better stereo-image, two or more speakers are great. I think many other speakers would work well also.
The A5 is a great choice, but a little expensive. Especially if you go for two in stereo. The A1 is nice for low volume sound nearby, but not for partying in a larger venue.
Use mains powered speakers. Or keep them connected to the charger. I have a B&O A1 next to my bed. It is always on and always connected to the charger. Just works. Amazing for audiobooks.
I use a B&O A1 on my bedside table. As long as it is plugged in to the charger, it stays on. Great to help me fall asleep. I use the audiobook player software in my phone to stop playback after 15 minutes, unless I move/shake the phone. If it isn't plugged in it will turn off with a beep after some minutes of stopped playback. I think almost all BT speakers work like this. Keep it connected to the charger and it won't turn off and beep. I have a dual output charger, so I can charge my phone as well.
Get a second hand beosound A1 gen 2 or 3 from bang and olufsen. You can get it around that price and it’s both gorgeous and a nice speaker, water resistant as well.
Check out the Bang & Olufsen Beosound A1. A true 2 way speaker, IMO this is a rather high fidelity bluetooth speaker when compared to many other models that may use full range drivers.
I have compared A1 and Emberton ii... the A1 has a more refined sound, and even more clarity, especially in upper frequencies. Also more balanced, sometimes Emberton will hit peaks and get pitchy. But Marshall adds a "reverb" color to most of their speakers so that's not surprising, and can sound more "fun" w/ certain genres. Emberton can get way louder. I own a Stockwell ii which is just super pleasant for low volumes, and has more balance than the Emberton also.

soundcore
Boom 2
Loud, bassy beast; needs EQ, no aux.

Bose
SoundLink Flex Series
Durable, compact, good for size; distorts at high volume.

Minirig
Minirig 4
Unrivaled sound, long battery; pricey, flaky Bluetooth.

soundcore
Motion+
Best value, excellent sound with EQ; needs EQ.

JBL
Charge 6
Durable, portable, clear bass; dull vocals, distorts up close.

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Anker - Select 4 Go

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Harman Kardon - Go + Play 3

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LG Electronics - XBOOM Grab

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soundcore - Boom 3i

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JBL - Boombox 4

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Anker - Select 4 Go