Hey, I'm brand new here, currently in the middle of building my first diy speakers, a small pair of 2 way bookshelves. I'm trying to keep things as simple as possible, and just have a first order crossover. I'm using the Dayton Audio ND25FA-4 tweeter paired with their TCP115-4 woofer. My crossover right now consists simply of a 0.23mH inductor in series with the woofer, and a 15MFD capacitor on the tweeter. The real issue though is that the tweeter is substantially louder than the woofer (by about 5db according to their spec sheet graphs) but as a beginner, on a mac, I haven't been able to find any software I can use to properly work out my crossover, and instead used a simple online calculator to work out the 1st order crossover. I know I can bring down the tweeter with a resistor, but don't know the math to figure out what size resistor I'll need to buy.
Any help from someone with a bit more experience, or access to proper software would be greatly appreciated.
Any help from someone with a bit more experience, or access to proper software would be greatly appreciated.
Can someone please explain Butterworth crossovers . . . in layman's terms?
If you are using a simple treble pass system, fit a resistor twice the value of the tweeter impedance in series with the tweeter and reduce the series capacitor in value to half.
If you are using a simple treble pass system, fit a resistor twice the value of the tweeter impedance in series with the tweeter and reduce the series capacitor in value to half.
Okay, so I would switch to a 7.5MFD capacitor, in series, and add an 8ohm resistor in parallel (after the capacitor?). Any chance you could give the equation for working that out? That or if its a standard concept I could look up, so that in the future if I need to adjust a speaker by 2db or 6db or whatever, I can do the math myself? I'm trying to figure out how much of this I can do by hand since none of the software will run on my computer.
Thanks for the quick reply though!
Thanks for the quick reply though!
Here's a useful source of information on all things crossover: The Crossover Design Cookbook
P.S. The resistor goes in series with both the capacitor and the tweeter.
P.S. The resistor goes in series with both the capacitor and the tweeter.
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The 8 ohm resistor and 4 ohm tweeter form a simple voltage divider.
Voltage Dividers - learn.sparkfun.com
The signal voltage is divided up in the same ratio as the resistances - in this case 2:1
So, the voltage (V2) which reaches the tweeter is only one third (0.33) of the full signal (V1).
You can convert to dB using this calculator:
Voltage to dB Converter
e.g. V1 = 1V and V2 = 0.33V gives -9.63dB
Voltage Dividers - learn.sparkfun.com
The signal voltage is divided up in the same ratio as the resistances - in this case 2:1
So, the voltage (V2) which reaches the tweeter is only one third (0.33) of the full signal (V1).
You can convert to dB using this calculator:
Voltage to dB Converter
e.g. V1 = 1V and V2 = 0.33V gives -9.63dB
