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## Re:Linkwitz transform 12 years 7 months ago #919

 devteam Offline Administrator Posts: 9145 Thank you received: 1456 Geez, you guys are starting to seriously compete with the LT spreadsheet running around the DIY audio forums...Neat! Keep up the good works and let us know how this implementation works on a real speaker prototype. Anybody out there already at that stage, maybe with measurements? miniDSP, building a DSP community one board at a time. Please Log in or Create an account to join the conversation.

## Re:Linkwitz transform 12 years 7 months ago #944

• knuisje
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In this latest version I added to the graph the equalizer as calculated from the digital coefficients. This is usually the same as the targeted equalizer as calculated from the original and target response. But when you fiddle with Fc and Fs you can see it can be different.
I also added a digital filter stabilty calculation. When the poles are within the unit circle the digital filter is stable. Enjoy!

## Re:Linkwitz transform 12 years 7 months ago #952

• knuisje
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Ok, I did some measurements to test the correct implementation. This is a close range measurement of a closed box. I used these parameters in my spreadsheet to calculate the digital coefficients for the biquad LT equalizer:

f(0) = 87
Q(0) = 1.1
f(p) = 50
Q(p) = 0.707

In the graphs you can see the results.

## Re:Linkwitz transform 12 years 7 months ago #953

• knuisje
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And the measurements.

## Re:Linkwitz transform 12 years 7 months ago #954

• knuisje
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## Re:Linkwitz transform 12 years 7 months ago #984

• knuisje
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## Re:Linkwitz transform 12 years 6 months ago #1062

 KAMIKAZE Visitor Hello to all, I just purchased minidsp kits and 4-way adv. plugin. Waiting for parcel I already build box for my Peerless XXLS 830846 - 58 liters. Here is measured parameters of it Fs = 25.43 Hz Qms = 10.67 Vas = 66.53 liters Cms = 0.376 mm/N Mms = 103 g Rms = 1.56 kg/s Xmax = 12.5 mm Xmech = 18.75 mm P-Dia = 212 mm Sd = 353 sq.cm P-Vd = 0.441 liters Qes = 0.4 Re = 2.6 ohms Z = 3.12 ohms BL = 10.23 Tm Pe = 175 watts Qts = 0.39 no = 0.257 % 1-W SPL = 86.25 dB 2.83-V SPL = 91.13 dB Could someone please help me with calculating Linkwitz transform for my box? And give some example. I just not understand all process... :-[ Please Log in or Create an account to join the conversation.

## Re:Linkwitz transform 12 years 6 months ago #1064

 KAMIKAZE Visitor Hi knuisje, Thank you for answer. As I understand, final Q(p) must be 0.5-0.7? and F(p) as lower as better? Can you please give some example with it(with calculated biquad's), maybe I do not really understand this. Thank you in advance. Please Log in or Create an account to join the conversation. Last edit: by KAMIKAZE.

## Re:Linkwitz transform 12 years 6 months ago #1069

• KAMIKAZE
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Ok, I think all done.

## Re:Linkwitz transform 12 years 6 months ago #1070

 KAMIKAZE Visitor and xls calculations p.s. can't attach image. here is the link rghost.ru/2624222 Please Log in or Create an account to join the conversation. Last edit: by KAMIKAZE.

## Re:Linkwitz transform 12 years 5 months ago #1118

• knuisje
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