This speaker from Stockholm-based Transparent Sound is, says the brand, "designed to last forever". 

The Bluetooth-enabled (there's no Wi-Fi) Small Transparent Speaker (yes, that's really what it's called) has a ‘closed-loop system’ which essentially means that some of the wireless components can be replaced rather than having to replace the whole unit every few years. The hope is that it won't become obsolete.

A compartment at the bottom of the speaker is what holds and powers the wireless components that will be future-upgradeable. 

That is appealing; if you're still using the first Bluetooth speaker you bought then you're doing well, have a gold star. 

Priced at $550/£450, it's half the price of the company's $1,100/£900 larger speaker which, as you can probably guess, is called the Transparent Speaker.

As you'd expect from a Scandinavian brand, it has a striking design. 'Unibody' is a word banded around mostly in terms of laptop chassis construction and this speaker frame is similar. It's constructed from one single aluminum ‘uniframe’ which is filled with tempered glass panels. It can be displayed either on a table-top or wall-mounted using included brackets.

TransparentThis speaker is designed to last forever - and can even be upgraded image 2

The Small Transparent Speaker boasts dual 3-inch drivers plus a Class D amplifier which powers its 2 x 15W output. You can also stereo pair the unit with a second Transparent speaker.

Interestingly, Transparent recommends pairing Small Transparent Speaker with Amazon's Echo Input for multiroom music over Wi-Fi and to provide access to Alexa. It can also be part of an existing Sonos set-up, using Sonos Connect or AMP hub.