^^yes, timebase not jpg if you mean that
so 0,026seconds?
and 8351 genelec for the reference
i know im doing something wrong
so 0,026seconds?
An externally hosted image should be here but it was not working when we last tested it.
and 8351 genelec for the reference
An externally hosted image should be here but it was not working when we last tested it.
i know im doing something wrong
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Its a mystery to me
I would assume that a higher order alignment (reflex or Karlson) would have poorer response in this regard due to phase shifts at tuning frequency/ies.
Perhaps the bandpass function has something to do with it?
Or gating frequency losing relevant data?
Must say I'm surprised especially with the K slot phase influences at the LP end if the bandwidth.
EDIT: Is this just the dipole? If not is the XO point below gating cutoff? Id guess a dipole is good in this regard, but that is just a guess. But conversely id think the time aberration from rear radiation would swamp any coherance in real listening I.e.ungated
This is a Z baffle dipole with a compression driver on the front firing driver. There is no gate applied and measurement is at 0.5m so any reflections would not be in the 4ms time frame.
It really surprised me how it worked out. It took small incremental time delay adjustments to get the skinny tweeter peak to line up to the leading edge.
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I don't think you are doing anything wrong, it's just that a triangle shaped step response is very rare and hard to achieve with a multiway unless you work at it and use the appropriate cross overs and have very wide bandwidth drivers.
My guess why it is working on the KaZba is that the woofer bandwidth is very wide and working almost like a fullrange, the tweeter is time aligned and adds the peak at the leading edge.
Agree totally. But this is why I find it so hard to evaluate step response plots. It either looks ok, or it looks a train wreck, with little between. I imagine that to the ear, the improvement is far less black and white. I.e. A middle ground step response, probably sounds less severe than the plot would have one believe.
There is an audible difference when you achieve a good SR. It is very evident with percussion. If you don't have it, you may not know what it sounds like and never miss it. Most people have never heard it I think with conventional speakers - they hear it in live music and know that live sounds live. When you hear it on speakers it sounds more realistic and live-like.
I'm sure it makes some difference, as a drummer myself, I know what drums sound like live. I doubt my speakers have as good a step response, but I do know they convince me on my own drum tracks.
So I remain a sceptic that it is so Night and Day, or Id be very unsatisfied with my home stereo. Besides, the only person that hears live drums is a drummer, drum close mic setups are probably the least like reality at least in regard to hihat and snare, and the bleed through which is normally removed. What is lovely is when an engineer captures cymbals well with overheads. I only have a few recordings that sound right as far as those aspects are concerned, either listening with headphones or speakers.
So.the sceptic in me believes, perhaps in error, that most of the perception is due to recording setup
I.e. When its recorded well, it sounds more correct; but on the majority of drum recordings ot can't improve
Anything. The old garbage in garbage out analogy.
Just my two cents
Perhaps those good recordings were mastered with transient perfect monitors? Pure speculation there, but possible...it seems many just use the usual powered monitors- maybe that's why they don't excel?
So I remain a sceptic that it is so Night and Day, or Id be very unsatisfied with my home stereo. Besides, the only person that hears live drums is a drummer, drum close mic setups are probably the least like reality at least in regard to hihat and snare, and the bleed through which is normally removed. What is lovely is when an engineer captures cymbals well with overheads. I only have a few recordings that sound right as far as those aspects are concerned, either listening with headphones or speakers.
So.the sceptic in me believes, perhaps in error, that most of the perception is due to recording setup
I.e. When its recorded well, it sounds more correct; but on the majority of drum recordings ot can't improve
Anything. The old garbage in garbage out analogy.
Just my two cents
Perhaps those good recordings were mastered with transient perfect monitors? Pure speculation there, but possible...it seems many just use the usual powered monitors- maybe that's why they don't excel?
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but...moving vaguely back OT
I would imagine and assert also, that a good step response isn't altogether due to wide bandwidth drivers, and phase alignment.
As long as mechanical breakups are sufficiently attenuated and phase is aligned too, I see no reason why less wide band drivers could be distinguished from wider bandwidth drivers filtered with lower orders. The sticking point is the larger phase shift involved with better stop band rejection. It would seem, with DSP that this is almost a moot point.
In my case, IF I have successfully eliminated breakups in the crossover, I would expect to see a ramped attack envelope from the woofer output, and then the maxima at around 0.5ms where the cycle delay from 4th order phase rotation delays the tweeter output, before HF output kicks in (I think I have that the right way around)
I really need to get a mic and REW and try it. The topic has piqued my curiosity for sure.
I would imagine and assert also, that a good step response isn't altogether due to wide bandwidth drivers, and phase alignment.
As long as mechanical breakups are sufficiently attenuated and phase is aligned too, I see no reason why less wide band drivers could be distinguished from wider bandwidth drivers filtered with lower orders. The sticking point is the larger phase shift involved with better stop band rejection. It would seem, with DSP that this is almost a moot point.
In my case, IF I have successfully eliminated breakups in the crossover, I would expect to see a ramped attack envelope from the woofer output, and then the maxima at around 0.5ms where the cycle delay from 4th order phase rotation delays the tweeter output, before HF output kicks in (I think I have that the right way around)
I really need to get a mic and REW and try it. The topic has piqued my curiosity for sure.
I just built a XO test bed to play with all these cool concepts. It's described here:
http://www.diyaudio.com/forums/multi-way/88135-filler-driver-ala-b-o-3.html#post4378443
http://www.diyaudio.com/forums/multi-way/88135-filler-driver-ala-b-o-3.html#post4378443
This 3-way Troels thread discusses solutions for:
1) 4" true-midrange as the key driver
2) 0.75" - 1" dome tweeter
3) 8" or 10" woofer
4) physical TM alignment vs. Xover tricks
5) how crossover phase shift affects sound quality
There are a few physically small NdFeB 0.75" -1" dome tweeters which integrate a very shallow waveguide which both provides time delay and directivity control. Tymphany BC25SC06-04 1"
There are a few "no-mounting" dome tweeters which can be inserted behind a shaped front baffle which provides time delay and directivity control. Tymphany OX20SC00-04 3/4" Fabric Dome Tweeter
DSP can easily correct driver time alignment but… The latest tech Kii speaker uses a DXT tweeter because even top DSP technology cannot control a tweeter’s directivity.
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