In order to better understand what the individual parts do in an XO, I have started playing a little with Xsim. It gives really good insight even just with a dummy driver.
I tryed with a SineCap filter for a tweeter, i.e. a coil in parallel with the tweeter, without a capacitor in series.
I have made this simple filter where C1 is "short". But there is no response in Xsim. The frequence is just af line at default 70 dB. Xsim can't do that or am I doing something wrong.
I tryed with a SineCap filter for a tweeter, i.e. a coil in parallel with the tweeter, without a capacitor in series.
I have made this simple filter where C1 is "short". But there is no response in Xsim. The frequence is just af line at default 70 dB. Xsim can't do that or am I doing something wrong.
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Xsim is correct. The amplifier is designed to supply a certain Voltage to anything connected to it. You have the speaker connected directly to it.
The inductor will likely cause damage to the amp by short circuiting it at low frequencies.
The inductor will likely cause damage to the amp by short circuiting it at low frequencies.
I also assumed that Xsim was correlate, but how is it then drawn in Xsim. Here is one from Troels Gravesen's elipticor. For me it is the same filter for the tweeter for the resistors.
Adding a reststor made alle the diffrend, now i tryed. But why . I would think that it just dampened, but it obviously also has an effect on the XO frequency, Very little resistance = staight line.
You have to use resistors in this kind of topology. There is no way around it.
Also, those resistors will pass a lot of current, and the tweeter will be taxed if not up for the challenge. If you are a beginner, I would not actually use one of these topologies for not possessing the knowledge required about them.
Also, those resistors will pass a lot of current, and the tweeter will be taxed if not up for the challenge. If you are a beginner, I would not actually use one of these topologies for not possessing the knowledge required about them.
These are basically amongst the earliest of all electrical filters & originated in the Victorian era:
https://en.wikipedia.org/wiki/RC_circuit
https://en.wikipedia.org/wiki/RL_circuit
That doesn't mean they aren't useful in some cases of course, but the occasional reappearance of this filter type under new names, e.g. 'SineCap', 'Diaural' etc., is perhaps the classic case of 'what once was [very] old is again new.' 😉
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Ohm's Law shows us that in order to expect differences in a FR of a driver, there has to be different voltage drops on circuit components at different frequencies. You will get a grasp of it once you start to manually calculate circuit values.
Scott, "SineCap" is the term Sonus Faber used for the original (and revamp of) Extrema speakers. Troels is just repeating the term as he sourced it from there.
Honestly, 'capless highpass' covers it fairly well. It was or is also used in quite a few car audio component sets like the one from MB Quart.
Shadowplay, do you really need the 68 ohm resistor? As large as that value is, it is not really doing much. Make sure the 8.2 ohm resistor is at least 25W and mounted on a heatsink, and that the coil is large awg so that the components will take the current. I believe that tweeter should be capable at its Sd.
Honestly, 'capless highpass' covers it fairly well. It was or is also used in quite a few car audio component sets like the one from MB Quart.
Shadowplay, do you really need the 68 ohm resistor? As large as that value is, it is not really doing much. Make sure the 8.2 ohm resistor is at least 25W and mounted on a heatsink, and that the coil is large awg so that the components will take the current. I believe that tweeter should be capable at its Sd.
Yeah, I know -the marketing department at Sonus have a habit of taking existing methods / solutions and inventing some fancy-sounding term for it to help flog product. 'Stealth Reflex' (aka 'lossy vent') was one. 'SineCap' is about the silliest of their efforts though, given that we're dealing with a basic RL high pass, first invented 130-odd years ago and is fact, one of the very earliest types of electrical filter. As I say -'what once was old is again new (at least to certain marketing departments 😉 )'. Not knocking it as a type of course -useful to have up the sleeve sometimes.
It does. Although I don't think I'd even bother with that, since it's had quite a pithy name since the Victorian era: an RL high pass filter.
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The amplifier is designed to hold a Voltage at it's output. It does this by it's impedance. You have to use impedance to break up that Voltage to where you want it. You make a circuit and put the speaker in the middle of it.
You are right, I know, it was just an example to replicate the x-over posted by Henrik.
Tanks for input.
I agree/know that there should be resistance at the start, Extrema had that too. Otherwise, the impedance will be extremely low. So maybe i should have drawn the resistor in the diagram. But since it was just to test the effect of the coil I omitted the resistance. It's a good thing I did it, otherwise I wouldn't have gotten all the input about the interaction between the resistor and the coil.
I agree/know that there should be resistance at the start, Extrema had that too. Otherwise, the impedance will be extremely low. So maybe i should have drawn the resistor in the diagram. But since it was just to test the effect of the coil I omitted the resistance. It's a good thing I did it, otherwise I wouldn't have gotten all the input about the interaction between the resistor and the coil.