It decreases rapidly with 12dB below the filter frequency. The 6dB filter reduces the level sooner, already well above the filter frequency, which means, yes, it reduces the excursion there a tad but below it rapidly exceeds the 12dB filter. Lower frequencies quickly lead to much higher excursions.
It's easy to try the effects of the filter order on a dsp, you'll hear the difference very clearly. If the 12dB xo does sound worse then it's because of a bad adding phase/level. On 6dB you won't hear that because of the huge overlap range and lower phase shift.
That strongly depends on the actual phase of the drivers. In theory perfectly right, on high xo frequencies the acoustical phase changes so fast, it can be wrong (-> supertweeter). Also, you don't change the polarity of the tweeter if you are using a dsp, you switch the phase in the dsp and store it in the settings. That way you can compare differnt filter setups without touching the speaker or the amps and get a direct A/B comparison.
I can only sign that. A decent router does cost something but you will use it a lot on speakers if you build them more than maybe two in a lifetime.
Please read my text again. I was trying to explain that driver excursion INCREASES (at 12dB/octave) as you you reduce frequency. So you need a 2nd order crossover just to maintain the same excursion below the crossover frequency. Excursion means potential for distortion.
But a 1st order crossover places potentially big demands on a tweeter. That can pose problems.
But you do need to reverse the polarity at some stage. It was just a reminder that you need phase reversal for phase to track properly in the crossover region, if you are employing 2nd order filters.
(Why does this forum have such a user-unfriendly approach when it comes to multiple quotes?)
In most cases, the first-order crossover is not only problematic for the tweeter, but also for the mid / low-mid driver (cone break-up, beaming etc..).
I didn't know if it was advice, but in the case of DSP, it is worthwhile to bring the driver's response smooth first, then give the desired slope, crossover frequency and timing. In this case, it is easy to modify the parameters of the crossover after listening.
As a curiosity, i recently read on a forum where someone cut a soundtrack and re-assembled it with a high-order (24dB/oct LR i think) crossover for testing the audibility of the phase shift while listening to headphones. His conclusion was that there was no audible difference between the two tracks. With this, I would like to say that it's worth a try a higher order crossover, you get lower distortion but different power response with multi-driver loudspeaker. First order filters has very low advantage if any with DSP.
I didn't know if it was advice, but in the case of DSP, it is worthwhile to bring the driver's response smooth first, then give the desired slope, crossover frequency and timing. In this case, it is easy to modify the parameters of the crossover after listening.
As a curiosity, i recently read on a forum where someone cut a soundtrack and re-assembled it with a high-order (24dB/oct LR i think) crossover for testing the audibility of the phase shift while listening to headphones. His conclusion was that there was no audible difference between the two tracks. With this, I would like to say that it's worth a try a higher order crossover, you get lower distortion but different power response with multi-driver loudspeaker. First order filters has very low advantage if any with DSP.
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That's exactly what I was saying.
Well, that's a lot easier because it's done with a dsp (or active) and you only 'hear' the filter itself. On a passive crossover the drivers are unfortunately often not that cooperative though and you do hear a difference.
Yes, I see it the same way.
I think we just misunderstood each other. Sorry for that.
Exactly. And this is the case here. The speaker is practically a 2-way with a bass below it, with a typical xo aimed at 2kHz. With 6dB you can't use the advantage of the woofers and are limited by distortion and likely excursion on the tweeter. There were several possible solutions mentioned here but 3wayaddict doesn't want to have any of it. I wonder what it's gonna be then.
I don't know either, meanwhile I'm used to it (still annoys me often though).
The only advantage of the 1st order filter i see, when the passive filter is electrically 1st order. The goodness is not because the 1st order acoustical slope (often not possible with 1st order electrical) but because of low impedance between the amplifier and the drivers. But with DSP or active analogue crossovers this impedance is as low as possible, having only the wire and connectors between the amp and the drivers.
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Ok, but this is a highly lossy procedure if done passively, more compensation means more loss. Loss of electricity (converted to heat) which is the music or sound itself. Maybe i am not right but i think it's audible.
Comparing the two extremes - power consumption in the driver will be the same, the Voltage is the same at all frequencies, the same current will be drawn through the driver at all frequencies, the response of the driver is the same, the directivity of the source isn't affected.
Okay, but that doesn't change the fact that a 1st order acoustic slope crossover requires exceptional drivers and in most cases I don't think this compromise is worthwhile to get fewer phase shifts.
I don't have an axe to grind but I hate it if someone (you) makes it sound a filter with a dsp would equally translate into a passive network. Because it does not, that's simply wrong.
Yeah, and in the process you're blowing tons of power and also huge ammount in parts for the network. Which in praxis is completely out of question. And a current source amp is not desireable in many cases either.
I lost track of this thread..
And the passive does not need amplification?
The DSP eats hardly anything.
Yes, active speakers needs several channels but that's added up is still a lot less than you are burning by dragging the spl down - passive it's impossible to raise the level and therefore you have to burn the excessive level (mainly) in resistors. That way you lose a lot more power, remember, with rising spl it's a quadratic equation!
The compensation of the impedance of a woofer will cost you ~120€ per side and you'll introduce serial resistances. That is everything but 'problem fixing at the source' - because that would mean, you'd do it before the amplifier. That problem solving at the source would be.. hmm.. a dsp maybe?
And the passive does not need amplification?
The DSP eats hardly anything.Yes, active speakers needs several channels but that's added up is still a lot less than you are burning by dragging the spl down - passive it's impossible to raise the level and therefore you have to burn the excessive level (mainly) in resistors. That way you lose a lot more power, remember, with rising spl it's a quadratic equation!
The compensation of the impedance of a woofer will cost you ~120€ per side and you'll introduce serial resistances. That is everything but 'problem fixing at the source' - because that would mean, you'd do it before the amplifier. That problem solving at the source would be.. hmm.. a dsp maybe?
Agree with many here, the target curve in the room should be gently dropping in level.
Secondly, I prefer a direct sound with a slight boost 1-2 kHz relative to 2-4 kHz due to the fact that you are dealing with stereo speakers that fire in an angle toward our ears. A perfect linear direct curve gives a timbral change of the phantom centre, and this can be adjusted with small changes in the frequency curve.
With respect to the BBC dip, I have mixed feelings. It depends if the recording has already compensated for the diffuse sound that the microphones pick up. I myself likes an image that falls behind the speakers (depth) and prefer in addition to the above, a bit lower power in the 3 kHz region.
Secondly, I prefer a direct sound with a slight boost 1-2 kHz relative to 2-4 kHz due to the fact that you are dealing with stereo speakers that fire in an angle toward our ears. A perfect linear direct curve gives a timbral change of the phantom centre, and this can be adjusted with small changes in the frequency curve.
With respect to the BBC dip, I have mixed feelings. It depends if the recording has already compensated for the diffuse sound that the microphones pick up. I myself likes an image that falls behind the speakers (depth) and prefer in addition to the above, a bit lower power in the 3 kHz region.
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