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+--- Thread: HP-97/67 HI FI Pac Part 1 Loudspeaker SEALED BOX (/thread-21409.html)
HP-97/67 HI FI Pac Part 1 Loudspeaker SEALED BOX - plore90 - 03-07-2024 02:42 AM
Hi everyone.
Here I am again to present you a HI FI package that which I had already published for the 41C, this time for the HP-97(and HP-67) and concerns the project of a Loudspeaker SEALED BOX. The program, which takes up two magnetic cards, is divided into two parts. The first part, contained in the "SEALED BOX HP 97_67" card, allows the loading of the THIELE-SMALL parameters relating to a given speaker via the LBLA with the relative printing and calculation of the EBP
EBP < 50 - use only for a sealed box
EBP 50 - 100 - can be used in either
EBP > 100 - vented box only
EBP > 130 - can be used for Horn Loudspeakers
Subsequently, after having entered the desired Qtc via the LBLB (total Q of the speaker in an enclosure including all system resistances) and pressing the E(RUN) button, it is possible to calculate the resonant frequency Fc of the chassis in the housing , the net volume in liters (or in dcm^3 ) of the box (No filling with absorbent material!), the frequency F3 where the level has dropped by 3 dB, DbPeak (Db) Frequency of maximum amplitude enhancement (for Qtc > 0.707), Fmax (Hz) maximum amplitude peak at Fmax (for QTc > 0.707) and finally the relative SPL of the Speaker with the Qtc of the SEALED BOX. By entering the desired volume of the BOX and pressing the C key, you obtain the results and the Qtc associated with that volume value. By pressing the D key, the values previously calculated with the E key (net volume) are calculated, this time considering the Loudspeaker BOX filled with absorbent material (Damped). The second magnetic card allows you to calculate the frequency response from 20Hz to 200Hz normalized to 1/3 or 1/6 of Octava of the Loudspeaker Sealed Box. The card can be read directly through the card reader after the results have been calculated with the first card without turning off the calculator or by inserting it independently after having turned on the calculator and having entered the Fc values (by pressing the A key afterward), Qtc (then the B key), 20 or 10 and C key (20 for 1/6 octave and 10 for 1/3 octave) and finally the E (RUN) key. It is possible to obtain the printing of a single amplitude value in Db by entering the desired frequency value and pressing the D key. It is important to highlight that the use of the frequency response card will overwrite the data of the program registers, possibly already ' resident in memory worked with the first card. Returning to the first card, once it has been read through the card reader and the speaker parameters have been entered, before continuing with the insertion of the QTC, it is advisable to save the primary registers of the 97 (or 67) on a magnetic card and archive it with the name of the speaker (Data Card) so as not to have to manually re-enter the parameters relating to that speaker again. Below is an example of using the two cards: If set FLAG 0 ON work well with HP-97 (PRINT results), Hp-67 users change instructions PRINT-X with R/S.
1) Read the "SEALEDBOX Hp 97_67" Card.
Enter the THIELE SMALL parameters of the Speaker
2) Enter Fs (Speaker Resonant Frequency) and press A
3) Enter Qts and press R/S
4) Enter VAS and press R/S
5) Enter SPL (Db 1watt/1meter) and press R/S
6) Enter Qes and press R/S
The EBP value will be printed
6a) (OPTION) Save the data entered in a Data-Card and write the brand and name of the speaker on it
7) Enter the Qtc value and press B
The system QTC will be printed
8) Press the E (RUN) key and the following will be printed:
Fc (Hz)
Vb (Liters or dcm^3)
F3 (Hz)
If Qtc > 0.707
Dbpeak (Db)
Fmax Dbpeak (Hz)
End If
Db(Fc)=20LOG(Qtc) Gain at resonance frequency
SPL(Global System)
9) Press D to calculate with Loudspeaker DAMPED or Enter Volume and C key to calculate given a desired Volume.
10) Repeat steps 7 to 9 as desired.
11) Insert the "SEALED BOX FREQ. RESP. HP-97" card
12) If the calculator still has the results calculated with the First Card
12a) Enter 10 (1/3 octave) or 20 (1/6 octave) Logarithmic scale and press the C key
12b) Press the E (run) key, the Fc and Qtc values will be printed and in sequence the frequency and amplitude in Db from 20 Hz to 200 Hz.
12c) enter any frequency between 20Hz and 200Hz and press the D key, the single frequency and Db for that frequency will be printed.
13) If the calculator does not have the results of the calculations of the first card in its memory, or was turned off,
enter Fc and press A, Qtc and press B, and continue from step 12a).
I hope that the program can be useful to anyone who wants to build a sealed speaker themselves and I hope to have the time to write the program for the project of a vented box loudspeaker.
Any corrections, suggestions or additions from you will be welcome.
Thanks for the attention
Plore90