Club Amiga de Montreal - CAM/CAM_CD_1.iso/files/306.lha/SpeakerTools_v1.1/SpeakerTools.docs

Text File | 1980-12-05 | 12KB | 297 lines

                                                      Oct 15, 89

                        SPEAKERTOOLS V1.1

Disclaimer: I do not warranty the correctness of the information
            generated by this program, and I decline any
            responsibility for any problems caused by the use of
            this program or it's output.

Conditions: This is a shareware product, if you like it and use
            it, I suggest a donation of $30 (private users), or
            $50 (commercial users). You can freely redistribute
            this program as long as you include this
            documentation with the program itself. Registered
            users will get the latest version and version 2.0
            when it becomes available. V2.0 will have better
            graphics a context sensitive help feature and a
            better X-Over section offering third order slopes
            and active filter designs.



Introduction

    This program is meant to help the hobbyist who builds and
designs his own loudspeakers. It allows you to design sealed and
vented types of enclosures, and will tell you the ideal
dimensions, frequency response and power output. It also allows
you to design crossover networks for 2 and 3 way speakers.

    If you already know about loudspeaker design than this
program should be self explanatory. If you're just starting than
this document and the program itself will guide you through the
process of loudspeaker design.

    This program uses the Small/Thiele approximations for
enclosure designs. If you notice any large discrepancy than
please advise me so I can correct them.

    This was my first Amiga project and my first Modula 2
program. It required quite a bit of work but in the process I
learned a lob about programming the Amiga. If you have any
suggestions, comments or bug reports, please let me know so that
I can improve this program and make it more useful.



Setup

    To run this program you should have the ARP (1.3) Library in
your libs: directory. Simply type "SpeakerTools" in the CLI or
double-click on the icon and the program will start, no arguments
required. You should use a stack size of at least 8000 bytes.

    I suggest you use a separate directory for all your driver
data files. You can then use the "Set Path" item from the
settings menu to tell the program where to look for these files.

    You can also change and save the default colours, I suggest
a light background with dark characters for best results.

    This program looks for its defaults in a file called
Speakers.dflts in the S: directory. If it doesn't find this file
it will simply assume some settings of it's own. After you've
setup the program the way you want (Using the Settings menu), you
can save those settings by selecting "Save Settings" from the
Settings menu.





Project Menu

    NEW : This menu item will clear from memory any data about a
specific driver (woofer), and bring up a window for entering
new driver data. If you change your mind, or lack some data,
you can get out of this function (and all the other functions
of this program as well) by clicking on the close gadget in the
left corner of the window. Once you've entered the last data
item, the window will close on its own. In this data entry
window, like in all the other ones in this program, if you enter
an out of range value, a requester will pop-up to warn you and it
will give the allowable range of values. You can cancel this
requester by clicking in the OK gadget, or typing the first letter
of the gadget (IE "O"). Once you are out of the requester, you can
enter an appropriate value to replace the old one.

    OPEN: This allows you to load a driver data file from disk.
This archive contains several files that can be used if you have
access to those drivers.

    SAVE: This will save the current driver data to disk using
the current file name. If no file name exists then the program
will ask for one.

    SAVE AS: This will ask for a name before saving the driver
data file, even if a name already exists.

    Quit: Self explanatory. If there is an unsaved driver data
file in memory the program will ask if you want to save it first.



Functions Menu

    VENTED BOX: This menu item allows you to design ported
loudspeaker enclosures. This type of enclosures is suitable for
drivers having a Qts (see glossary) between 0.2 and 0.5. You have
the choice to do an OPTIMUM or a FORCED design. Optimum will give
the best performance while forced allows you to tune the
enclosure to your own taste. If no driver file was loaded from
disk, the program will ask you for the driver data at this point.
If you don't have access to this data, see the "Find Params" menu
item. After you've entered all the data the program will display
a graph of the frequency response and the appropriate data,
including the enclosure volume and cutoff (-3dB) frequency.

    From this screen you can RESIZE the enclosure to suit your
needs, PRINT this design (screen dump), ENCLOSURES will give you
the ideal dimensions (golden ratio : 0.6 x 1.0 x 1.6, these
dimensions include an extra 10 percent for internal bracing and
insulation and are only recommended)but you can now change those
dimensions for the given box volume, POWER OUTPUT will ask for
some more data(watts should be RMS) and give you a chart of power
levels at various frequencies, and VENT DESIGN will ask you for a
vent diameter and give you the proper length.

    FORCED will do exactly the same thing except it will start
by asking for an enclosure volume and tuning frequency. This is
useful if you need some particular performance characteristics
that do not correspond to the ideal (flattest response) provided
by the OPTIMUM option.


    CLOSED BOX: This will allow you to design a closed (sealed)
enclosure. Drivers for this type of enclosure should have a Qts
of 0.3 or higher. This section works the same as the closed box
one except that the program will also ask you for a Qtc (see
glossary), Qtc should be between 0.5 and 2.0.


    ENCLOSURES: This is exactly the same function as the one
available from the Closed and Vented design screens. It allows
you to find out the dimensions of an enclosure according to the
volume you provide. It will first give you the golden ratio
dimensions. You can then change the volume or any of the dimensions
to arrive at the exact box design desired. If you enter a new width
in the appropriat gadget, the depth will be corrected to arrive at
the given volume, same thing if you change the height. If you
enter a new height. If you change the depth, the height will be
modified to maintain the proper volume. All those dimensions
include an extra 10% for bracing and insulation. The program will
show you what the box will look like.


    VENTS: This is the same function as the one available from
the Vented design screen. It acts as a calculator, you enter a
box volume, a tuning frequency and a tube diameter, the program
will calculate the proper vent length.


    X-OVERS: This will allow you to design a 2 or 3 way
crossover network with any mix of first or second order (Butterworth)
slopes. You will be presented with gadgets arranged in a graphical
way representing the crossover. You can change the impedances by
clicking in the appropriate gadgets and entering the proper value.
Same goes for the crossover frequencies. You can change the
individual slopes by clicking in the slope gadgets, they will toggle
between 6 and 12 dB/Octave. When you're satisfied with the data,
just click on the DONE gadget. The program will then draw a diagram
with the proper values of capacitors and inductors. Be sure to check
the proper polarity on the drivers. From this screen you can select
RETRY for another design or select PRINT to send this one to the
printer (screen dump).


    FIND PARAMS: This will allow you to find the driver
parameters when you don't already have them. To do this you will
need a VOM, an audio frequency generator and a test enclosure.
You will be asked for the driver's DC resistance (use the VOM),
the free air resonance (frequency at which the impedance is
highest), the frequency at which the impedance equals the
calculated Z below and above the free air resonance, the volume
of your test box (sealed) and the resonance frequency with the
driver mounted in the box. When you enter the last data, the input
window will close itself and the program will display the calculated
data. You are now offered the choice to SAVE this as a driver data
file for later use, PRINT the data, start all over AGAIN or QUIT.


UTILITIES MENU

    CALCULATOR: This one will translate between cubic feet and
liters or between inches and centimeters. Simply enter the proper
value in the appropriate gadget and you will get the converted
value in the other gadget. Clicking on the MODE gadget will
toggle between volume and length units. This runs as a separate
task and can be kept in the background at all times.

  FREQ.GEN. : This will bring up another backgroung task that will
allow you to use your Amiga as an audio frequency generator to help
you use the FIND PARAMETERS function. It will generate triangular
waves from 6 to 13300 Hertz (it doesn't work well above 7000 Hz yet).
You have gadgets to START a sound, STOP a sound, QUIT this function,
and select a different frequency range. You can also use the
proportionnal gadgets to change the frequency within a range, or
adjust the volume. You should feed the audio output of your Amiga
to a small amplifier to get enough power to drive your speakers.
This module can be sent to the back like the metric calculator.

  If you re-select the CALCULATOR or FREQ.GEN. menu options while
the task is already running, it will simply become the frontmost
window.


SETTINGS MENU

    SET UNITS: this will allow you to chose between the METRIC
and ENGLISH modes. Unless you then select the SAVE SETTINGS item
the program will revert to it's default setting on the next run.


    SET COLOURS: this will bring up a colour palette allowing
you to change the screen's colours. Again, unless you then select
SAVE SETTINGS the program will revert to it's default colours on
the next run.

    SET PATH: This will bring up a file requester to allos you to
select the path for your driver files directory. You should than
save this path by using the SAVE SETTINGS option.


    SAVE SETTINGS: See above if you don't already know how to
use this.



INFO MENU


    ABOUT: this is self explanatory.


BUGS:
~~~~~
  There is a small bug in my compiler that will cause some small
inacuracies with numbers displayed in StringGadgets. This is not
to worry about as the right number is still used for internal
calculations.


CONCLUSION:
~~~~~~~~~~~
  I hope you will enjoy this program and find it useful. It
required a lot of work and can still use some improvements, so any
encouragement will be most welcome. Only 3 persons registered V1.01,
common guys, I'm sure there is many more than that using it. This
makes me wonder if it's worth all the trouble, and if anybody
actually appreciates my efforts.

    Please send me any bug reports, donations or comments via mail or
leave me an EMAIL on CompuServe (76056,1655) or BIX (slyduf).

  For user support and free upgrades, registered users can contact
The Hobby Board (my own BBS, will come online in November 89)
24 hrs/day, 300-2400 Baud, at 403-456-7593.


    Here's a registration form for your convenience:

----------------------------------------------------------------


               SpeakerTools V1.1 Registration Form

Last name:____________________ First name:______________________

Address:________________________________________________________

City:_________________________ Prov/State:____________

Country:______________________ Postal code/ZIP:_______

CIS ID:_______________________ BIX ID:________________

Comments:_______________________________________________________

________________________________________________________________

Send to:
        Sylvain Duford
        14103-114 Street
        Edmonton,Alberta
        Canada, T5X-1R6