Inspired by the great work from @kaykoch you can find here i designed my own take on a satellite case for a raspberry pi 3a+, a Respeaker 2 mic hat and a small mono speaker.
You can find all the files and more pictures here:
Johannes
Very nice case, especially because it’s very compact and only one cable is going out. Thank you for sharing 
Also a nice and compact design. I’m interested in that small speaker you are using. How would you rate its sound quality on a scale from 1 to 10? Could you please provide a link on where to buy it?
They are available from different manufacturers. Adafruit has it but just search on ebay or amazon for 3 watt arduino speaker and you will find it.
Sound quality is like 4/10 but more than enough for feedback.
Wouldn’t want to listen to music with it 
Ok, thank you very much for that information. I think some community members might find them interesting because of the small form factor.
I found these which sound a little better than the other model:
I finished work on both the case for the Pi 4 and the adapter that allows to use the better sounding speaker. I will print a prototype of both and if they are good release the files on Thingiverse.
Looks great 
Thanks for sharing the development process with us.
Where did you find the cad for the mini “iLouder” speaker? Recently purchased some and couldn’t find cad models on the web. If you made them yourself, would you mind sharing?
i made one as I didnt find one either.
You can find it here:
Johannes
Thanks! I would have just used your case, but all I have are 3b+s
I upgraded all mine to 4s a year ago so i cant help there and themore case options there are the better 
After testing I had to redesign the adapter for the mini speaker to hopefully better fit the cables and case. I will make another test print before I publish it on thingiverse.
It fits both the pi 4 and 3a+ case:
Looks nice, what do you use the button for?
When you publish, mind sharing a step file or similar? I’ve recently purchased an expensive amount of pi 4s… however I want to add an isolated air quality sensor location and may toy with isolating the speaker from the mics.
Suppose you couldn’t also make a cut out for one of these?
You would probably need a different lid design too? I guess you would mount an usb sound card internally and connect a electret?
Yep or x2 if you can run 2x KWS at say 180, 135 or 90 degrees its sort of pseudo and cheap beamforming.
Also maybe you could create some electret mounts that also double as isolation from the internal speaker.
Not really sure about the electrets you will get the style of a slotted tube that maybe are external parts that clip / screw onto sides or base?
I fart on about that Boya purely as its prewired but really its too big and overpriced.
What would you use as an amp for the speaker?
I would probably need to buy all the components so that I can actually measure them.
The one I like at the moment but that is by soundbar preference.
But always like these but take wattage ratings with a pinch of salt.
Options use a single channel and have speaker outs on the case?
Also if you could beef up the speaker?
https://uk.rs-online.com/web/p/speaker-drivers/4318686/?
https://uk.rs-online.com/web/p/speaker-drivers/1976441/?
With a silicon pad maybe they could be a great heatsink ? (who knows)
Plus connect a button to the pi run as its a reset but on shutdown will start again even if a different power button to one we know.
I have my fingers crossed we may see a Pi4A+ and price reduction on the 3A+
The class D amps always seem to be a bit ‘hummy’ when idle and like the Sanwu’s I have seen because build quality seems reasonable but also has a standby input that with an alsa hook we could prob hook up to gpio.
