Just spent some money increasing/improving my backyard patio area. I'd like to install some outdoor sound that can be easily fed via bluetooth as well as utilized for when I setup a TV or projector outside. Any recommendations for amp/receiver and wireless vs wired speakers?

If you live in a tract home, as most people do, you have neighbors very near by.  Loud outdoor audio is generally a bad idea.

The thin walls of your home will absorb almost all the higher frequency stuff and attenuate the bass to some degree,...when played indoors.  Out of doors, you the overall sound pressure level will go up and the neighbors will likely become unhappy if it happens repeatedly or too late at night.

Ah,..., you knew all that, right?

I'm in the wilderness.

I, personally, would never even consider wireless speakers.  (I'm ignorant of current models but just can't imagine them being as good as wired when considering sound quality, ease of hook-up, durability, longevity, etc.)



Think about something from the JBL Professional line for your speakers. I figured if they were good enough for theme parks, restaurants, bars, church's, stores, etc then they were good enough for my back patio and went with a pair of Control 28's (non-transformer version).  (Found a set on Ebay that were relatively inexpensive.)



Is your patio covered, with some part not exposed to the rain?  



Bluetooth wasn't an option for me at the time but I got a cheap, used, smaller-than-standard-sized receiver and a small cabinet from Home Depot and hung it all under the patio. Plugged in a portable CD player (an auxiliary Bluetooth adapter is available for a similar setup if you have an old stereo receiver laying around).  Painted wires and conduit the same color as the house to camouflage them and ran them on the exterior side.



Sounds really good for a patio rig and is still going strong, about 10 years later.  It may seem like a hassle now but the tunes are worth it once you get everything in place - you'll be glad you did.





 

I've got an old Onkyo receiver/amp so I thought about putting it in my garage then running wired outdoor speakers. With wireless speakers, I'd still have to run power to them so there'd still be wires anyway so might as well just use an amp with wired speakers.

Then I could use one of those bluetooth aux in adapters. That way I could either use the receiver itself as the source or feed in sound from my phone or tablet or whatever.