Enceintes de bibliothèque Mini Cube 100W Paire de haut-parleurs à cône en papier de 3"

What sort of connection do these use? Is there a pic of the back?

You can check this link to view the back side of the speaker

https://www.parts-express.com/Pyle-PCB3BK-3-100-Watt-Mini-Cube-Speaker-Pair-Black-310-2004

Where is AC cable?

These are passive speakers

Will these (bluetooth) hook to Boes Smart 300 sound bar or to new PT694BT receiver?

No it will not. the PCB3BK are passive speakers which require an amplifier

Can you hook up to a TV?

These are passive speakers that need an amplifier to make them work

How do the pull tabs work on the back of the speakers when hanging them?

Press Tabs and insert the wire on the slot for positive and negative

How do I install the mini cube speakers to an old (1991) Aiwa stacked stereo system (CS 790-U)?

The PCB3BK has a standard wire connection

How do I hook these up

It hooks up like a standard speaker with RED and Black  speaker wires to an amplifier receiver

Is this an "old school" speaker as in can i plug my rca jacks from my 2000 era Technics receiver into and get great sound

These are passive speakers with spring loaded push clips

Is this particular set Bluetooth capable?

These are passive speaker

What are the spring loaded connections for? The ones above the speaker wire connections on the back.

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