A wired, powered speaker for use with the pipistrelle mini bat detector, because wired speakers are getting hard to find. This is 65mm tall by 44mm wide, about 10mm deep and uses the Taoglas 36mm 4 ohm / 1W speaker driven by a 50p PAM8302A audio amplifier. Input resistor to the amp is set at 39k to give an overall gain of 3.0, which compensates for the -6dB response of the pipistrelle mini output circuit, to give me (fingers crossed) 4.5V p2p from a full-scale signal out of the pipistrelle, so we will just hit the rails when at full volume using 1.5V AAAs (i.e lithium or alkaline batteries)

The 3D print incorporates a "bass reflex port" which is honestly laughable, but all tests with the Taoglas have been very tinny, I'm just trying to help the low end in any way that I can.