Question:  

Why are there no power cables in the box with the SRX 900 series speakers?

Answer:

There is an inlet and outlet Neutrik Powercon connector included with each speaker.  Each speaker's amplifier has and Inlet to power the speaker and an Outlet to connect a jumper to power the next speaker(s).  Each speaker has 2 Neutrik Powercon connectors in the box, 1 to connect to the Inlet and 1 to connect to the Outlet.

Here are links to each connector's assembly instructions:

Power Inlet - NAC3FX-W-TOP   -  Download .PDF
 

Power Outlet - NAC3MX-W-TOP  -  Download .PDF

Note- There are NAC3FX-W and NAC3MX-W connectors available on the market as well as pre-made cables made with these connectors, but the -TOP version has a better weather rating. Both connectors will fit.

You will make 1 cable with the NAC3FX-W-TOP Inlet connector on one end and the power connector of your location on the other.  The cabinets can run from 100vac to 240vac.  The power supply is universal.

You can also create jumpers with an Outlet to Inlet connector to be able to jump cabinets together from same power feed line.  There is more in-depth information in the manual but here is a guideline:

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