New memberUsername: Jipiedra
Post Number: 1
Platinum MemberUsername: Jan_b_vigne
Post Number: 18230
Not a strict rule but more a truism in audio; you get what you pay for.
Onkyo's "zone 2" operation is a good example of why this is true.
You can explore self powered speakers though such designs require a power source of some type; either a battery which needs to be recharged or changed out or access to a live AC outlet. If the AC source is not easily accessible, then you could find you're paying more to provide the power for the speaker's amplifier.
For background music levels only, you could very likely get by with a small chip amp such as this; https://www.amazon.com/M50-2x50w-Tripath-Stereo-Amplifier/dp/B006K7AT26
The Muse line of amps is sold worldwide and there are other manufacturers producing similar products that might even be less expensive. Use a search engine with "class D amplifiers" in the title.