CondensatorenFilter
This is the filter design. There is some flexibility in component selection. Inductor DCR does not matter. The components I used were supplied from Madisound. The cap is a Bennic poly, the resistors are Eagle metal films, and the coils are air core standards. The one critical part is that the small inductor must be a .08 mH. It can't be a .10 or a .05. This means you have to have the coil custom made or you can buy a .1 and unwind it to what you need.
For unwinding a coil, the important thing to remember is number of turns is not a linear relationship to the inductance. Unwinding a .10 halfway does not equal .05 for example. Go to Lalena's inductor calculator, enter the gauge, spool length and spool inside diameter for both a .10 and a .08 to find the number of turns for each one. Subtract the two and you'll know how many turns to unwind from a .10 to make it a .08. Note that this is very accurate but only works for air coil. Before you start unwinding, you can do a sanity check on the .10 by confirming known numbers like the DCR and outside diameter, with what the Lalena calculator shows up. Or forget all that and pick up a cheap LCR meter from MCM. # 72-6634 is on sale right now. I have one and it's really nice. I can't imagine life as a speaker builder without it.
When you construct this crossover, do it so resistor R2 is easily removed and replaced. That might mean using some kind of terminal, binding post or other quick release method. R2 is a baffle step compensation resistor. Adjusting R2 is the key to making this driver fit your application and preference. For most people, R2=8ohms will work the best. Use that as a starting point and read on below.
I don't know where I got a Bennic Poly 4.3 uF cap, nobody sells them. 4.7 is too big and 3.9 is too small for this. You can parallel a 1.0 and 3.3 to reach this value however.
De 4,3uF condensator is -zoals ZaphAudio schrijft - niet te vinden.
Dit is op te lossen door 1.0 uF en 3,3 uF te nemen.
Hier zijn weer allerlei soorten in. Welke voldoen?
Bipolaire, mooi goedkoop.
MKP, stuk duurder. Maar klinkt zeker ook stuk beter?
Weerstanden
R2: voor de baffle step, de waarde hiervan is afhankelijk van de plaatsing.
10W Metaalfilm Oxide weerstand voor R2
4W Metaalfilm Oxide weerstand voor R5
Luchtspoelen
SP-0.82MH-1 - Visaton coil with air core and tinned wire ends 0,82mH (5013)
Internal resistance 0,4 Ohm
Wire diameter 1,0 mm
Diameter 48 mm
Height 18 mm
LU25/008/071 - Lucht spoel 0.08mH 0.19 Ohm 0.71mm
Al bij al toch zo'n 20 euro/speaker.
Kloppen de vermogens, types, afmetingen zo? Iemand op/aanmerkingen?
Is dit niet veeeel goedkoper actief te filteren?
Heb 8 filters nodig voor mijn surround set.
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lees zojuist prijzen tussen 12 en 20 euro per speaker...