How do you break in your new / recone woofers?

[sebackman]

Hello,

I did some search but did not really find much info.

I have a set re-coned JBL 1400PRO and I just wondered how you break in your woofers?

These are seemingly brand new 1400PRO cones in K2 1400Nd baskets. I think the baskets are the same so that should be fine, however they are very stiff.

I also have a pair of LE1400H with new edges and is there a need to break them in with new foam edges. If so what would you recommend?

Kind regards and thank you
//RoB

[Ducatista47]

I am fairly certain a series of suggestions will follow citing what passes for orthodox figures. Hours, days, weeks, using break in CDs or files, or loud classical music, etc.

I go with JBL, which did research on the subject years ago. A generous time frame was one minute. The actual results were that if there is such a thing as cone driver break in, it happens in the first half second playing music. I don't remember where I might have saved the file of the paper; it was a long time ago and it was very easy to remember the conclusions. I don't make it a habit of arguing with JBL engineers or their test cells. FWIW I don't doubt anything Harry Nyquist at Bell Labs came up with either.

Now let the audiophile advice commence.

[DavidF]

Hello,

I did some search but did not really find much info.

I have a set re-coned JBL 1400PRO and I just wondered how you break in your woofers?

These are seemingly brand new 1400PRO cones in K2 1400Nd baskets. I think the baskets are the same so that should be fine, however they are very stiff.

I also have a pair of LE1400H with new edges and is there a need to break them in with new foam edges. If so what would you recommend?

Kind regards and thank you
//RoB

I just put them in the cabinets and start listening to music. Others may have a different approach such as placing the cabinets face-to-face and wiring one speaker cabinet out of phase from the other (cancels out much of the output). Then play a test signal CD on auto repeat for a day at a moderate amp output. For me that's just too much trouble.

[gasfan]

I recently refoamed the 122As in my L65s. I used them exclusively and it was at about the 3 month mark that I thought how great the bottom end is. Great definition and extension.

[Wagner]

Hello,

I did some search but did not really find much info.

I have a set re-coned JBL 1400PRO and I just wondered how you break in your woofers?

These are seemingly brand new 1400PRO cones in K2 1400Nd baskets. I think the baskets are the same so that should be fine, however they are very stiff.

I also have a pair of LE1400H with new edges and is there a need to break them in with new foam edges. If so what would you recommend?

Kind regards and thank you
//RoB
Just use them, same as you would/did the first time around
Break in is a mechanical thing (the compliance loosening up) and there is no universal answer
Actually, there is no answer at all as the ambient temperature in one room will change the answer (time required) for another room with a different ambient temperature just to cite one example of what a useless term it is (meaningless)

All of this being based on the assumption that the new outer compliance/cone kit/foam is even physically capable of re-creating what the originals did compliance wise; in other words, depending on the part, it's installation etc etc etc they may NEVER "break in" and meet a factory/engineering specification, especially if the parts are aftermarket, but even then "break in" is nothing to worry over as I guarantee that the foam edges on a genuine JBL cone kit will be different in some way from the same part number manufactured 30 years ago

After you play them a while you will absolutely hear when they open up and you will know that that is the moment that the new outer compliance reached an optimal state

Make note of when that happens and there you will have your answer of how long it takes to "break in" new cone kits/foam surrounds/outer compliance

Running lots of LF stuff will obviously help speed the process up

This post is sort of rambly and for that I am sorry; what I am trying to say is just use them and they'll open up and you'll hear it and you'll be fine and you'll be done.
There is no optimum "break in" methodology as there can be no actual target that we are trying to "break them in to".............once you start flexing outer compliance surrounds with music you have begun a process that will never stop until the next compliance failure..................like the shock absorber on an automobile

Just play them

[1audiohack]

Same as Wagner, I just play them.

I am not mean to them at first and that is likely due to the life long belief that all things mechanical arrive at their engineered sweet spot after a certain amount of time, revolutions, heat cycles or what ever. I never saw the need to hurry that along with my drivers.

My two bits and it might not be worth that. :)

Barry.