A bit rough and ready but at least its well protected and will have a clear acrylic top for the Wifi to get in and interested audio geeks to see inside…
Mains power wire in and speakers out…it doesnt get much better than that…
Into a pair of Emotiva ERM 6.2 bookshelf speakers (4Ohm) at vulme level 40 its a reasonable level for a dinner table area…50 for general listening and 80 is starting to get into a loud party…up past that is getting pretty darn loud 
LESS IS MORE
Moved your post here for fellow Tinkerers to admire Paul. Imagine what you would pay for similar functionality off the shelf !
I’ve guessed it’s a Pi3 using the inbuilt WiFi ? Some users have found that a little flakey but have no problems adding in a USB dongle with antenna. Some of the Realtek dongles available in Australia need a Linux driver and there is a remarkable fellow called MrEngman who maintains a repository for RTL8192EU drivers.
Next time you may want to consider giving the Pi a little breathing room… 
Thanks Andy … Hope this inspires some holiday DIY madness for others…but IQAudIO is closed now till the new year…just got my goodies shipped out in time yesterday.
I thought I would use this case (leftover from a stereo BTL LM3886 amp build) as I wanted something heavy enough to not have it ripped off the table by the speaker cables…But maybe for the next one I will just mount the unit on the back of one of the speakers and be done with it an a pi casing (that should arrive today) along with 2 more pi’s as the guys at IQAudIO are OOS for pi’s but the 2 x DigiAMP+'s and power supplies are on the way to me buy post 
Great WAF too…all would hide behind the speaker.
Very very happy with the results…props to Dan @ DietPi and Gordon at IQAudIO…awesome job.
So far no issues with the basic onboard WIFI but there is always the option of a USB dongle or wired LAN too.
I let it just sit there idling overnight and fired up Roon today and hit play and it burst to life with music completely hassle free.
One of the best little projects I have done this year. 
I know the Pi uses stuff all power but one of the advantages of DietPi is that it writes logs to RAM and only accesses the SD card every now and then (forget how long). This means a power off shutdown (as distinct from a Linux shutdown through a terminal) has a greatly reduced chance of corrupting the SD card. I’ve been using the volume knob power off on my Pi2Design Tube HAT with no ill effects.