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doc/TinySpHEAR_simple.md

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+# The *SpHEAR Project
+
+## TinySpHEAR
+
+The TinySpHEAR microphone is a traditional 4 capsule tetrahedral first order Ambisonics microphone. 
+
+![TinySpHEAR](pictures/TinySpHEAR.png "TinySpHEAR")
+
+The four capsule holders come in two flavors, one for the upper two capsules and another for the bottom two capsules that connect into the microphone mount. The capsule holders have legs with fingers that interlock and hold the structure together. There are two styles of usable interconnections, horizontal legs (easier to print and assemble, a bit bigger) and vertical legs (more difficult to print and assemble but more compact).
+
+![TinySpHEAR, horizontal legs](pictures/TinySpHEAR_10mm_hlegs.png "TinySpHEAR with horizontal legs")
+
+![TinySpHEAR, vertical legs](pictures/TinySpHEAR_10mm_vlegs.png "TinySpHEAR with vertical legs")
+
+Both pictures are renderings of a microphone with 10mm capsules. 
+
+There is a third style of legs intended to print the whole microphone structure in one go in a more sophisticated 3D printer, but this has not been tested.
+
+![TinySpHEAR, angled legs](pictures/TinySpHEAR_10mm_alegs.png "TinySpHEAR with angled legs")
+
+A couple of configuration variables in the source file can be used to switch to a "print" rendering where the individual parts of the structure are laid flat on the printing surface.
+
+![TinySpHEAR ready to print](pictures/TinySpHEAR_capsule_print.png "TinySpHEAR ready to print")
+