I just finished this typical Bluetooth speaker and wasn't going to post anything, but I wanted to give my impressions on the Peerless Ta6FD00-04 speaker.
I'll quickly go over the parts and specs of this build. The box is internally divided using .25" mdf, and approximately .055cf after the Bluetooth components. I used half inch Pvc about .9" long for a tuning of 88hz. I used the csr8645 apt-x, a DC/DC step up convertor, a micro usb charge pcb, and a one high quality 18650 battery. A simple filter was used for the speakers. I had some buyout .52mh coils left that I paralleled with a 10ohm resistor in line with each positive line of the speakers.
Now for the sound. I was pleasantly surprised these $10 speakers could put out some usable midbass while sounding so smooth. Pretty happy especially considering it came in under $50. These would also serve well in front of the computer as PC speakers.