A few words...

Horn parameters:

Horn M-factor
This program is able to manage exp/hyp horns only
M-factor = 0.0 makes catenoid
M-factor = 1.0 makes pure exponential
0.0 < M-factor < 1.0 makes exp/hyp

Area throat:
This is your choise. I think the calculated value gets unrealistically
small compared to the recommendations from the driver manufacturer.
My formula might be incorrect.

AThroat (Calcd):
This is the throat area calculated from:
2 * pi * driver_resonance * Qts * Vas / soundspeed

Calculation step:
Cannot be less than 0,001 m

Horn total volume:
...is the absolute minimum volume you need to box the lab if the labwalls
and the outerwalls are not accounted for. This is no real world but might
give you an estimate of the HWAQ factor before you go any further with your
20Hz subwoofer horn for the bathroom.

Area factor:
Areas through the labyrinth are simply multiplied with this parameter. If you
want to split up the horn into two similar ones, set area factor to 0,5 and
create only one of these twins.

Length factor:
This parameter gives you the opportunity to shorten or lengthen the horn.

If you want to create a real single labyrinth standard horncabinet, true to
the formulas, keep both factors at 1,0.

Cabinet parameters:

Width, Height, Depth:
...are related to the rectangle drawn in the labVW window
Width goes into (or out of) your monitor
Height is the Y-part
Depth is the X-part of this rectangle

LabVW (labview) window:

Here you see the labyrinth inner walls based upon the current parameters
and the created lab circles and extensions.At the end of each lab circle
plus extension a line is drawn across the labyrinth. When the centreline goes
 no further, you have reached the throat of the horn, and the area of the lab
gets no smaller from here.

You may change any horn or circle parameter and see the result immediately
Sometimes though you have to click the Calculate button to get an updated
view

Labyrinth control:

The lab is drawn, starting from the mouth as a series of partial circles
with an optional individual linear extension from where the circle ends

The circles make out the centers of the labyrinth at a given point and the
inner wallpoints are calculated from the area of the horn at the relevant
distance together with the current angle

You add or delete circle(s) by rightclicking in the control window. You can
only add circles from the top down (mouth to throat).

The starting point and starting angle of the labyrinth kan be manipulated as
Centre X, Centre Y and Circlestart for the first (top) circle only.
You might say the starting point and angle for the following circles are
inherited from the end of the preceding circle.

CW/CCW for the selected circle gets toggled by clicking the cw/ccw header in
the control

Select the circle for edition by selecting the line.
Select the parameter for edition by clicking the relevant radio-button
Adjust the parameter by the Increase, Decrease buttons with LabVW window opened

Angles are in radians: 0.0 - 2.0

This is not an overwhelmingly intuitive interface, but to me it was ahoal quicker
than the method of trial, error, paper and pen, I started out with


Printing the result:

This is where the program really lets you down. I never got that far in the
development of CaHD. I could wait no longer to see (read hear) the result of
my efforts and solved the problem this way:

I made LabVW window as big as I could and took a windows snapshot of it.
Pasted it into some drawing program and printed it out as was.

I meassured the X and the Y of the rectangle from the printout and scaled it
into real values (big picture). I drew som random lines across the picture
and printed it out on several sheets so that the drawing overlapped from
sheet to sheet.

I taped it all together using my random lines as guidelines and glued it on
some plywood to cut out a model. End of this story. The start of a new :-)