If you remove group delay...what benefit does a low order crossover have if the speaker is perfectly able to support high order crossovers (48db)....a low order. I read the thread and feel no closer to the answer
So low order has less group delay, and high order has better polars and time alignment potential? So high order wins because people neglect group delay all the time? Or because linear phase has no group delay?-
I found this
that thread was from 2003 so...take from it what you will. I've been trying to figure out the sonic benefits of low order crossovers, outside of group delay, for my project. The only issue with group delay I have is at the crossover from my 15" mid to the horn. Some people claim they can't hear group delay issues up top, and even more have pushed the idea for bass.
Frequency Delay Dispersion | audioXpress
I don't know if this source is trust worthy but if hes legit then minimum phase for me it is....
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lol you tell me!? Well if they don't cross over in bandwidth...they have less potential for conflict within the time domain right? Isn't banding on the vertical axis due to phase cancellations at crossover? If we increase the crossover bandwidth, won't that intensify? The difference in group delay between two different drivers covering the same band doesn't cause phase issues? Comb filtering?
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In my understanding, the higher order slopes have less overlap bandwidth so the off-axis anomalies have less bandwith to appearing.
Maybe its likely only a potential problem, not a guaranteed problem... each case is unique or something...I dunno, but I am sure ready to be schooled =)
The transfer function of second order in Laplace transform is s²/(s²+w/Q×s+w²) for the high pass and w²/(s²+w/Q×s+w² for the low pass. if you add the low and the high pass , the band pass function (w/Q×s)/(s²+w/Q×s+w²) will be missing. The higher is the Q the less is the missing band pass sound. I never read on this website about this issue , but J. Hiraga's magazine concludes after trials the 3rd order butterworth to be the best.
What Q are we even talking about? The Q of the filter, or the Q of the resulting response?
Cross a wide bandwith mid to a tweeter, and I can assure you that the slopes will not be the same with the same filter Q.
Cross a wide bandwith mid to a tweeter, and I can assure you that the slopes will not be the same with the same filter Q.
I assume that we are talking about the acoustic Q. What would be the point talking about the filter Q in isolation? Filter Q needs to be such to get an acoustic Q that we set as goal. The final acoustic Q that is matters in loudspeakers.
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assumptions is the mother of all screw ups
What you might know, other might not and vice versa.
If there was EQ used to flatten the frequency response around the crossover point what difference would it make?
I wrote this in my last post. I don't know why it's missing
"We see lots of us using Xsim Like a video game, Creating a flat sloped response, with good phase tracking and a smooth off axis response, 1st,2nd,3rd,4th order variants plus combos. The various blends are subjectively different."
"We see lots of us using Xsim Like a video game, Creating a flat sloped response, with good phase tracking and a smooth off axis response, 1st,2nd,3rd,4th order variants plus combos. The various blends are subjectively different."
If the flattening happens to the individual driver responses before the crossover filter applied, then it helps to reach the desired final acoustic slope (and Q ofc) of the drivers when the crossover filters are applied. For example if we apply a Q=0.5 filter to a flattened driver response, then we get a Q=0.5 acoustical slope and it doesn't matter what EQ we used to reach that.
I hope I understood your question well.
I think you understood my question. What you suggest is equivalent to how a Linkwitz Transform works. If we assume the whole system to be minimum phase, then if the resulting FR is flat on axis, it shouldn't matter how we get there? There may well still be subjective differences dependent upon the characteristics of the drivers relating to off axis, power response etc with different Qs
And it's been suggested that a dome tweeters personality is primarily related to
"to off axis, power response etc with different Qs" and very little to do with the tweeters Electro Mechanical problems.
"to off axis, power response etc with different Qs" and very little to do with the tweeters Electro Mechanical problems.
I think that one reason a lower Q crossover is desired is with typical cone-dome combinations. The dome tweeter comes with it's very wide dispersion whereas the larger cone mid(woofer) is starting to beam with much narrower dispersion. The lower Q crossover creates a lower total output (power response) above the crossover where the tweeter have very wide dispersion. So creates a more balanced power response in a reflective environment ( aka listening room).
With a controlled directivity tweeter, there is less need or even undesired that lower Q crossover. All this IMO, maybe IME.
With a controlled directivity tweeter, there is less need or even undesired that lower Q crossover. All this IMO, maybe IME.
I've come to realize it is a mistake to consider an entire system minimum phase.
A system is really a set of minimum phase regions stitched together to become non-minimum phase.
Typical xovers are not minimum phase. (IIR xovers )
Nor are any summations of drivers that don't operate as an acoustic point source together. (such as coaxial, triaxial, synergy etc.)
Individual drivers are minimum phase, but once combined, nope...
Ime, it's why adding EQs to a speaker in xover regions seldom works (other than to a narrow specific listening spot)
It's also why different "Q"s at same xover freq will sound different, due to different polars.