^
There is no appreciable difference in measured TS parameters beyond 2 hours preconditioning. For some drivers even less.
"Memory effect" is a controversial theme, I will let it to Dave to explain it.
There is no appreciable difference in measured TS parameters beyond 2 hours preconditioning. For some drivers even less.
"Memory effect" is a controversial theme, I will let it to Dave to explain it.
So, we have published T/S parameters...or we have small signal parameters, or large signal parameters, or we have non-broken-in , or we have broken-in, or we have memories, hoping they are good memories, or we have hot & humid days, or we have cold & dry days...
or we have, "Did I hurt your wittle feelings"?.............I see lots of of anthropomorphism.
------------------------------------------------------------------------------Rick....
or we have, "Did I hurt your wittle feelings"?.............I see lots of of anthropomorphism.
------------------------------------------------------------------------------Rick....
Last edited:
Memory effect mentioned by @planet10 has nothing to do with TS parameters measuring, but with something called "masking effect of inappropriate signal during driver burning-in, which has detrimental and eternal effect on sound quality during audiophile listening, experienced as veiling the fine music structure and catastrophic loss of details and micro-dynamics reduction". Something of this may be real, though. I am open-minded.
You are putting your haraphrased understanding of what i was saying in quotes implying that was what i said, it was not. Some of what you said might be meaningful, but it is largely word salad.
dave
dave
That is true, but if you brutalize the suspension of some drivers they will never reach their maximum potential.
dave
I was not haraphrasing you, and I apologize if you understand it was directed at you - not at all, it was not my intention. English is not my mother-tongue, so I may not expressed myself as I intended.
I just cited (in quotes) something which is circulating among the audiophiles.
Last edited:
What is the ideal way to burn-in drivers please?
Is it the same for tweeters, mids, woofers?
Music, sine wave, pink noise, white noise?
Start at low level and build up gradually? Or something else?
Perhaps you could explain what you mean. Surely the suspension has reached it's full flexibility or it hasn't?
Mostly work with full-ranges. On the break-in bench for 200-300 Hrs (2-3 weeks) at low level with FM.
dave
But what is the linearity (or whatever the design curve is) between zero and full flexibility. Did it get stretched in a specific way?
dave
Does that matter though? To reach full flexibility it will have had to pass through zero numerous times. It's an interesting idea but I don't see the mechanism, as I said the only references I could find to memory effect relate to prolonged periods of no movement. Have you any references you can show?
Then it's not what is referred to as memory effect? Masking effect doesn't seem appropriate either since it requires a masking signal surely?
^
The story about memory effect is: all moving parts (spider, surround, cone) during burning-in somehow "absorbs in the memory" the burning signal, so after burning-in it will interfere with music during listening, obscuring fine details. If that signal is, say, 70 Hz sinusoidal, then it will emerge during listening. That is the logic behind music signal only, very long time, low level, audiophile certified burning-in.
My engineering logic tells me that after very long time (100 - 200 hours) non-repeating music signal accumulated in the memory (if real) is identical to a pink noise, or in the engineering terms: sum of 200 hours random music is pure pink noise. So my recommendation for 2 hours pink noise signal.
The story about memory effect is: all moving parts (spider, surround, cone) during burning-in somehow "absorbs in the memory" the burning signal, so after burning-in it will interfere with music during listening, obscuring fine details. If that signal is, say, 70 Hz sinusoidal, then it will emerge during listening. That is the logic behind music signal only, very long time, low level, audiophile certified burning-in.
My engineering logic tells me that after very long time (100 - 200 hours) non-repeating music signal accumulated in the memory (if real) is identical to a pink noise, or in the engineering terms: sum of 200 hours random music is pure pink noise. So my recommendation for 2 hours pink noise signal.
Last edited:
I don't know much about the memory effect, but this sounds reasonable to me. Even I don't believe that a 100h period is necessary.
After SEAS and Scan-Speak in #17, the conditions for T/S parameters by JBL for 2226H:
Last edited:
With that technique it is not possible to reach Xmax (or, the break-in is limited to a very small proportion of suspension). During normal music listening it surely will hit Xmax, creating much stronger memory effect from the first real-life level music signal, annihilating previous 300-hour effort.
But with low-level music it is impossible to reach Xmax, so the full flexibility is not reached! That is why I recommend 2-hour pink noise with high enough amplitude to hit Xmax. It may be sensible to start the first 15 minutes with low level pink noise, though.
Linearity is easy to measure with Klippel system.
Yes, I don't understand the aversion to pink noise, it is used extensively in audio for good reason.
Small details are radiated by the cone at all positions of it's travel, so again, pink noise at Xmas appears perfect.
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.
dave