Explain to me how bluetooth works in the following situations

In My Humble Opinion
1

I’m always about 5+ years behind the latest tech.

I’m curious how bluetooth works in the following situations and what items you have to buy to make them work.

You have a music player that doesn’t transmit in bluetooth, but you have a speaker that receives bluetooth signals. What item do you need so the player can transmit sounds to the speaker?

You have a music player that transmits in bluetooth (like an amazon echo) but the speakers you want to use do not receive bluetooth signals. What item do you need so that the bluetooth signals can be received and interpreted by your speaker system? How does it change based on the input of the speakers (3.5 jack, RCA, HDMI, etc)?

You have a bluetooth music player, but it only sends signals to one speaker. But you have multiple speakers all throughout the house and you want them all to play the music. What item will allow a music player that only transmits to one speaker be able to transmit to 3+ speakers all throughout the house?

You have an item that transmits in bluetooth, but you have multiple speakers you want to use (maybe a bluetooth speaker, but also the inbuilt speaker of the music system). How do you ensure the music comes through the right channel in the right situation. Sometimes the inbuilt speaker, sometimes the bluetooth speaker.

I assume for all the situations above there are items you can buy to make them work but I don’t know what they are called.

2

in both cases you’d use something like this:

edited to add: we bought a few of these at work a while back. they usually work, although some devices (like SYNC) don’t reliably pair with it.

3

So a transmitter will send bluetooth signals from a non bluetooth source to bluetooth speakers, and a receiver will accept bluetooth signals from a bluetooth source and convert them to signals that the speakers can accept? That is pretty simple, and as you said there are devices on the market that can do both.

What about the other issue I was wondering, what if you have something like a phone or amazon echo and you have 4 bluetooth speakers all over the house, can you get an intermediate electronics device so that 1 bluetooth signal can be sent to that, then 4 bluetooth signals are sent to the 4 speakers?

What about an easy to use bluetooth switch so you can easily switch between say internal speakers vs. bluetooth speakers, or maybe one set of bluetooth speakers vs another?