...My engineering logic tells me that...
Use your engineering logic to imagine how all those fibres in a spider are 1st arranged, stiffened, and then how does that complex structure age. Can you stretch fibres from where they are supposed to be? What we don’t know about that really quite complex mechanical structure to make a gross gues slike hitting it with a whole bunch of signal that over time is uniform.
That uniform signal (including level), can, i suppose, stretch the fibres in ways they were not meant to be stretched particualrily if the designer wanted the stiffening and the fibres to slowly reach maximum flexibility. That strecth would be a memory.
Think deeper. You are only thinking on a macroscopic level, forgetting that chaos happens at all levels.
I pay attention to ehat the designer says he intended.
dave
With that technique it is not possible to reach Xmax
We do not want to reach Xmax until well after the spider has had time to get ready to be strecthe dthat far.
If you break in only for maximum stretch to get the extents of the T/S and kill that driver’s ability to reproduce very small detail. I am after quality, bit quantity.
Just like an engine, you usually don’t take a brand new car and se ewhat happens when you rev it over the redline? It might still work, but will it reach its maximum potential?
dave
So does the pink noise, which is the most chaotic signal possible, far more chaotic than your recommend low-level music.You are only thinking on a macroscopic level, forgetting that chaos happens at all levels.
Just like an engine, you usually don’t take a brand new car and se ewhat happens when you rev it over the redline?
It may be sensible to start the first 15 minutes with low level pink noise, though.
Is that statement supported with some Klippel measurements of linearity?My schooling in memory came from a superb/skilled spider designer who stated that some of his spiders were designed to take 1500 hrs to break in properly. Not the norm, but what guys like this know far exceeds what we can imagine.
So does the pink noise, which is the most chaotic signal possible, far more chaotic than your recommend low-level music.
A chaotic signal with a fairly uniform frequency distribution but for it to do the job in 2 hours, it is the high initial levels that whipe out all the subtlety. If you started at very low levels and slowly. ramped up in level for many many hours might approach the same levelk of randomness in level & content but the designers do not what you to use it.
dave
I didn't find it before. Please post such measurements.Probably if you dig deep enuff.
... but for it to do the job in 2 hours, it is the high initial levels that whipe out all the subtlety.
It may be sensible to start the first 15 minutes with low level pink noise, though.
Not the norm, but what guys like this know far exceeds what we can imagine.
Maybe, maybe not, I wouldn't like to say 🙂
That uniform signal (including level), can, i suppose, stretch the fibres in ways they were not meant to be stretched particualrily if the designer wanted the stiffening and the fibres to slowly reach maximum flexibility. That strecth would be a memory.
I can see how it would be reasonable to increase the level over time, I still don't see there's a problem with pink noise though.
What if you hit a pothole first time out, will the suspension no longer ever be able to deal with small surface ripples? 😉Just like an engine, you usually don’t take a brand new car and se ewhat happens when you rev it over the redline? It might still work, but will it reach its maximum potential?
I didn't find it before. Please post such measurements.
If you haven't found it, I doubt very much it exists.
I see what seems to be an interest in avoiding dwelling on one particular level of the excursion.
Isn't the old rule of thumb regarding softening up any material, to go slowly at first to add heat, and to avoid creating creases or micro level rips and tears? (All of which would happen at some particular location, if that isn't the definition of memory.) Wouldn't a low frequency sine represent the most gentle approach?
Isn't the old rule of thumb regarding softening up any material, to go slowly at first to add heat, and to avoid creating creases or micro level rips and tears? (All of which would happen at some particular location, if that isn't the definition of memory.) Wouldn't a low frequency sine represent the most gentle approach?
Isn't the old rule of thumb regarding softening up any material, to go slowly at first to add heat, and to avoid creating creases or micro level rips and tears?
Well said.
dave
That is what I do. Less noisy when at full excursion. But it only works on the suspension, not on the breakup modes of the cone. When designing on those a bandwidth-shaped pink noise is better.Wouldn't a low frequency sine represent the most gentle approach?
I like pink noise better. And I suppose a full-level sweep could bring out resonances in an intensity never reached with normal music. I've seen wrinkled paper cones in my life... But no other arguments come to my mind now.
I think pink noise is better than a sine wave sweep so the speaker doesn't forget how to do quick directional changes at all points of it's journey. 😉
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