Makes sense to me and I can't tell what exactly @mark100 point is just yet. Mark, its like you are telling us how you feel about Phase, on a personal level.
Delay moves The start up Transient.
Phase moves Where exactly the Phase Angle is, at Start up.
By moving the Delay without changing phase, The phase angle at start up does not change but its relationship between redundant sources does and its just a matter of synchronizing between multiple sources.
These aspects are Frequency Dependent.
These aspects are Frequency Dependent.
everyone here understands this...
Still talking about phase? I thought it‘s quite simple. We have absolute phase. That is what is measured/heard at the receiving point in space. To know what the ‘relative’ phase at the source is, you have to correct for delay. Funny thing is: delay messes up phase relations between different frequencies. So while your source is so nicely behaved wrt phase behavior, the distance between it and your ears ruins this behavior (be it with a given function). You have to wonder why people talk about linear phase behavior of speakers all the time… they certainly cannot hear it in their listening chairs.
I have explained why you are incorrect, but as often the case with you, you just don't want to accept it. That's fine, I'll let you believe what you want. But the underlined part of the quote is incorrect since the mathematical relationship holds at any frequency, not a specific one.
No I think delay and phase are different.
Delay = fixed time. Nothing more.
Phase = a relative rotation of frequencies cyclical alignments. Nothing more.
I feel folks make understanding Phase complicated because they view Phase to be Absolute phase, which includes fixed time Delay.
I think Absolute Phase is a useless and confusing measurement. Delay needs to be removed for any type of usefulness.
And I think that understanding xovers and time alignments is more difficult than needs be,
until one sorts out the difference between fixed time Delay which is not frequency dependent, and Phase rotation which is frequency dependent.
Once that fundamental difference is clearly seen, I feel folks will see xovers and time alignments as much simpler than they thought.....hence why I keep ballyhooing this...
Yes, the math holds for any frequency across the spectrum.
My point has been that the math gives a frequency dependent "delay", and hence cannot be considered a true Delay (which I have tried to make clear I view as a single constant fixed time.)
We've had a discussion about Delay like this in the past.
https://www.diyaudio.com/community/...ompression-drivers.329235/page-7#post-5593199
We found agreement then i think ....once delay was defined as constant time.
They are different and similar. Its all based around positioning Cycles per Frequency
If a speaker is really linear phase it will not show any group-delay distortion. It will behave like that independantly of listening distance as long as we leave room acoustics out of the question.
Regarding the phase <-> delay interchangeability discussion: It is Important to use the actual phase for calculations and not just 0 to 360 degrees.
Regards
Charles
I think it's simple too 🙂
And yes, we must remove constant Delay from absolute phase to get to relative phase ( ie real phase).
I personally think/feel our ears and brain remove constant delay, such that we do hear the relative phase behaviour of the source speaker, after the sound has traveled to us.
An allpass filter can create a phase shift while the delay remains the same.
A delay can be created while the allpass phase remains the same.
A delay can be created while the allpass phase remains the same.
Hi Charles, yes for sure.....
....provided we remove constant Delay from the measurement, huh? 🙂
I'll continue to argue there is NO phase <-> delay interchangeability, till the cows come home.
(if shooting for a truly optimal solution)
And,........ if you stick to linear phase, you'll never need anything past 0 -360 degrees 😀
It's always easy to win an argument when you get to define the terms to suite your position. I'll stick with the mathematical definitions which do not require that delay be a constant. Under that definition phase and delay are synonymous.
That definition is pragmatically worthless....
care to tell me how you tune a speaker with it?
What is constant delay??? Are you talking minimum vs excess phase??? I don't remove any delay from my measurements unless you are talking about windowing and impulse response??
Rob 🙂
Hi Rob, constant delay is simply the fixed time between the stimulus signal and measurement.
It includes time-of-flight, and processing latency, etc.
In REW for instance, it would be time vs loopback.
When this constant delay is removed from a measurement, we see relative phase without all the time induced phase wraps.......
...that no one can easily make any sense of....
Hello Mark
OK in Clio choices are Normal Phase which includes all, Excess wrap's by themselves and Minimum/driver phase. You can see all 3 separately and use minimum for crossover design which is just the driver phase.
Rob 🙂
I'm considering this to be close enough to find out.
As measured at my listening spot using APL_TDA as the measurement tool.
This particular graph is optimized to show timing (includes normalization), should one want to see the frequency curve (non normalized) that belongs to that graph, there's an AFR button on the measurement program. It belongs to a suite of tools which also includes EQ etc. I just use the timing tool APL_TDA along with REW's tabs for measurements. You can run the demo to find out what it does: http://aplaudio.com/conc2/products/tda/
See here an example of a second order Troels Gravesen designed speaker in a studio-like environment (with a passive Haas kicker at 25 ms): https://www.diyaudio.com/community/...ions-and-analysis.273971/page-26#post-4581713
And also another graph from my own speakers back in 2016, which was quite different in setup, but not that much in timing. It's obvious from this comparison I'm in a real (living) room.
See here an example of a second order Troels Gravesen designed speaker in a studio-like environment (with a passive Haas kicker at 25 ms): https://www.diyaudio.com/community/...ions-and-analysis.273971/page-26#post-4581713
And also another graph from my own speakers back in 2016, which was quite different in setup, but not that much in timing. It's obvious from this comparison I'm in a real (living) room.