Detailed information on Helix-hmf160a

The 3D-Spiral Horn Speaker Building

Detailed information on Helix-HMF160a

Added on 28. Dec. 2008

	Making "R" at the edge of the fin using a router.
	16 fins needed for a pair of cabinet. All the fins have the same shape. width:65mm length:193mm angle: 7degree
	Opening a baffle hole with a cheap milling machine made in China.
	The all parts. Fins were glued on the side plates. There were questions inquiring the reason of using fins. The reason is the easiness of the building. If you feel it is easier to use single plates, it may be right.
	Aluminum tube on the fins.
	Trial assembly 1.
	Trial assembly 2.
	The finished assembly.

Measurements of Helix-HMF160a

Added on 28. Dec. 2008

Because of malfunction of the microphone (Primo EMU-4535-2), the new one (Microphone Madness MM-TMM-1) was used.
Therefore, a direct comparison with old data is not appropriate.

Resolution 21.53Hz ; Span 22050Hz
Magnitude -140 to 0 dBFS (FS : full scale)

measured with DCU-F101W

listening position

stereo,2m,center

mouth output

mono
center
(border of the mouth)

High resolution measurements

Resolution 5.383Hz ; Span 5512Hz
Magnitude -140.0 to 0.0 dBFS

	listening position stereo,2m,center
	mouth output mono center (border of the mouth)

Impedance measurements

Vertical axis has an arbitrary linear scale and is proportional to the impedance of the driver.
Resolution 5.383Hz

Comparison of Helix-HMF160a with HMF160

Added on 28. Dec. 2008

Resolution 21.53Hz ; Span 22050Hz
Magnitude -140 to 0 dBFS (FS : full scale)