Had a pair of accuton for many years, bought the same drivers to build another pair of speakers and they sounded vastly different in the beginning, it took a long time for them to sound the same as the old drivers.
Don't listen to those who claim that it need to be measured to be proven.
Don't listen to those who claim that it need to be measured to be proven.
The break in of suspension components can be, and has been, measured.
The question is, can the hypothesised break in of metal/ceramic cones be measured?
Nobody here (including me) dispute break-in effect of the driver suspension (spider + surround) - that is well known fact.
The remaining question is whether there is a break-in effect in metal/ceramic cones? Nobody here presented scientific evidence about that. Evidence may be purely subjective by ears, or objective by measurements - but only when it is done on the same driver, before and after brake-in, following scientific method. How can we find where the measured/heard difference come from - suspension or cone break-in? Please restrain from anecdotal "evidence".
In my professional work I have witnessed many broken metal cones/domes, but those were accidents/failures from massive overdriving, not "normal brake-in" effects from normal usage. Jordan-Watts metal-cone modules can prove that - they are the same now, as they were 60 years ago.
OK, but where the difference come from - suspension or cone break-in?
We all agree - there is measurable and subjective difference coming from suspension break-in. But what about cone break-in?
Of course it can be measured.
But The thing that really matters in the end, is, can_you_hear it?
The notion that the materials used used in a speaker would defy physics and be absolutely resistant to material changes, by useage and time, is nothing but a very bad joke, at best 🙂
And thats Fully Regardless of material used in the speaker.
But The thing that really matters in the end, is, can_you_hear it?
The notion that the materials used used in a speaker would defy physics and be absolutely resistant to material changes, by useage and time, is nothing but a very bad joke, at best 🙂
And thats Fully Regardless of material used in the speaker.
OK, so you_heard_metal_cone_break-in. So far so good.
Now, please present double-blind, level-matched, before and after cone break-in, subjective test. Pretty please?
Otherwise, metal_cone_break-in_you_heard is purely anecdotal and completely useless.
Now, please present double-blind, level-matched, before and after cone break-in, subjective test. Pretty please?
Otherwise, metal_cone_break-in_you_heard is purely anecdotal and completely useless.
Well…🙂
First Start here: Give me the evidence that i actually have claimed that i have heard that. 🙂
First Start here: Give me the evidence that i actually have claimed that i have heard that. 🙂
Sonce, I am sure he doesn’t care to spend the time (and expense to do properly) to execute a test, to he just wants to enjoy his hifi.
May i add to your demands. The test needs to be done in a temperature/pressure/humidity controlled anechoic chamber.
dave
May i add to your demands. The test needs to be done in a temperature/pressure/humidity controlled anechoic chamber.
dave
But in that case OP question can not be answered!
Nonsense! It can be done in any studio/hall with good acoustic. All proper studios/halls should have temperature control. Likewise, humidity is easily controlled also. As for the air/atmospheric pressure, there are plenty of days with the same pressure, and barometers are not that expensive.
Well?
A reduction in driver suspension mechanical compliance may not have as large an effect on the sound as one might expect.
I read that the performance of the loudspeaker is dominated by the smaller compliance of the volume of air within the enclosure.
While operating normally, an already broken in driver can see a further, temporary compliance drop, perhaps due to the suspension warming up.
Maybe an undampened metal cone is more susceptible to smaller changes (due to "burn" in/"break" in/temperature change) of compliance that a surround provides to terminate cone resonances, when compared to cones made from other materials.
Ah yes, the burn-in, break-in, settle-in, optimized crowd...the ones that will say...how do you define "nasal sound", I'd start will a calibrated microphone & a "pre" and "post" broken in drivers. Proponents of this fantasy would have one test this theory in a temperature, pressure, humidity controlled anechoic chamber...no doubt, THEIR listening of "the obvious" was not performed under such rigid conditions. Why should I jump thru these hoops when you do not?
The only "break-in" that is happening is an individuals perception of change. Stick to the measurable facts & don't bother with any ones "I swear, I heard it"....to those, I'd say, prove it.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
The only "break-in" that is happening is an individuals perception of change. Stick to the measurable facts & don't bother with any ones "I swear, I heard it"....to those, I'd say, prove it.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
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I am not much of a believer in speaker break-in. The metal cone will not play as much of a factor.
If you look at a driver and do some measurements with a rule you will find that much of the effective cone area includes the surround material.
Also the spider plus the surround make up the suspension. The stiffness of the suspension is subject to warmup and temperature to a much larger extent than break-in.
For grins do a TS/P measurement frequency sweep cold and again after twenty minuets of warm-up in a warm room and note the change in the TS/P values.
Thanks DT
If you look at a driver and do some measurements with a rule you will find that much of the effective cone area includes the surround material.
Also the spider plus the surround make up the suspension. The stiffness of the suspension is subject to warmup and temperature to a much larger extent than break-in.
For grins do a TS/P measurement frequency sweep cold and again after twenty minuets of warm-up in a warm room and note the change in the TS/P values.
Thanks DT
Let's assume for the sake of argument that a metal cone driver is affected by break-in. How much time and what kind of signal at what level is required before any significant change can be observed you think?
How many microns thin is it? What diameter? What shape? My CHN-50's are somewhere between aluminium cans and food-grade foil. The Alpair 5.3s are probably about the same, except that I haven't had any need to repair them yet. With enough time, I could probably convert SPL into PSI or pascals. You'd probably only want a small fraction of a newton of air load.
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Also, notice what happens at different frequencies. Why does the cone excursion diminish with decreased wavelength? It's not just the cone changing direction more often and therefore moving a smaller distance. It's also the air becoming a lot stiffer. There is less time for the compression forces to propagate away, and if you apply an acoustic lens like a wave-guide or horn or something like that, the opposing forces increase even more, so the cone hardly moves at all, so at some point it's all flex and no 'pistonic' motion to speak of.