HP-97/67 HI FI Pac Part 2 Loudspeaker BASS-REFLEX Enclosure New UPDATE!!

[plore90]

Hello everyone,
here I am again to present my latest BASS-REFLEX97_67 version of the BASS-REFLEX loudspeaker project after having presented the version for CLOSED-BOX some time ago.This latest version has been optimized and simplified, allowing the user to choose the project parameters more freely. The program is made up of 2 magnetic cards to be used in sequence, BASS-REFLEX97_67 12, BASS-REFLEX97_67 22. Attached, in addition to the 2 magnetic cards with their respective listings, each in PDF format and in .hp97 format ready to be used with the LimpidFox HP-97 simulator,you will find a sample data card with the necessary input data of KEFB110 Woofer. The program, after reading the first magnetic card (1of2) e after manually entering the following THIELE-SMALL parameters of the driver in the respective registers (Fb(optional) sto A, Fs sto B, Qts sto C, Vas(litres) sto D and Vb(litres), chosen by the user, sto E), by pressing the A key, it first calculates the resonance frequency of the box for the chosen box volume (if it had not already been stored in register A) and then after having printed Fb,Fs,Qts,Vas,Vb in sequence, it will calculate (in about 2 minutes..) and will print the cut-off frequency at -3dB of the woofer that will be mounted in the box. By entering any frequency from 20 to 200 Hz and pressing the B key, the gain in dB for that frequency will be calculated and printed. If the results are not satisfactory for the user, it will be possible to choose a new volume for the box and recalculate the new cut-off frequency F3 using the A key. After inserting the second card, by pressing A, you will get a printout of the Ripple(Db). By inserting the Diameter(Cm) of the Fb tuning tube (>=4cm) and pressing the B key you will get a printout of the relative length of the vent Lv(cm).The pipe length must be less than 3360 / 7*Fb else you might get organ type resonances! in it (Display Error!). By also inserting any frequency F(Hz) between 20 and 200 Hz here, you will obtain the output in dB for that frequency. Using the C key, after having typed one of 10(1/3dB per octave) or 20(1/6 dB per octave) or 40(1/12 dB per octave) you will obtain the printout of the frequency response of the BASS system -REFLEX (Box + Woofer) from 20 to 200 Hz. You can always start from the beginning by choosing another driver or another volume and inserting the first card again to carry out the new project calculations.
As usual, I hope that the program can be useful to some people who are nostalgic for old HP calculators like me, also out of simple curiosity to discover the renowned potential of these calculators. Suggestions and/or corrections from any of you are welcome.
Thanks for the attention.
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UPDATE Card 12 12/05/2024 !!!!!!!!!!!! Improved the find algorithm for F3(-3dB) now circa 40" second's
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plore90