Breaking in new speakers -BROWN NOISE

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The real requirements as mentioned are to stretch the suspension. You want to move the driver to it's limits without applying a lot of heat to the VC and risking damage. As several have said, playing a tone at Fs is the ideal way. You keep current low while being able to drive the woofer farther. The only problem is that you can still hear it and it can be quite loud. I typically do a 10hz tone for break-in on most all woofers which is below audible limits. Free air, it won't take a lot of power to move the driver to excursion limits. 90% of break-in occurs within about the first minute or so of pushing a driver to it's suspension limits.

As an interesting note, ideally you want a driver that doesn't change much over time. Some materials change much more. A cloth surround with phenolic resin will change more than a foam surround and a rubber/santoprene surround will change even less over time. Typical phenolic resin on spiders breaks down over time. The old method for getting a stiff spider is to add a lot of resin to the cloth. Over time that resin will break down more and more. Eventually you're left with just the stiffness of the cloth alone.

I've been working a lot to find better methods for this. Right now I choose three different base stiffness cloths depending on the end result I want for compliance. When the resin breaks down over time, the cloths left are still different stiffness. While this seems very simple and common sense, many still use one cloth with three different amounts of phenolic resin but in the end they all end up the same.

Another thing I've been working on is different treatment to the cloth. Phenolic resin really just sits on the surface of most cloths. Some soaks in, but to get more stiffness it just gets piled on the outside. By nature it isn't very flexible which is why it breaks down. I've been working with various other methods for coating/soaking the cloth. Much more flexible coatings that will not change over time are available but don't fit standard processes at this point. Much better materials are also available such as non-woven cloths that are not going to have the variation of woven materials. In order to use these materials though will take a lot of experimentation and the spiders won't be formed in the standard ways. That means I need to also design equipment to make the spiders before this becomes a reality.

John
 
Actually, breaking in speakers is a fact, the materials used for spiders and surrounds will go through subtle changes with use. What most of us technical types don't give much credence to, are the claims that things like interconnects and speaker wire need to be broken in. So as far as I'm concerned, mechanical things may need breaking in, but non-mechanical things don't. As far as claims that using one type of signal over another is a better way to do it, well I think it will happen quicker with signals that mechanically exercise the drivers more, but just normal use will also do the job.

Mike

That is true and Vance Dickason also ran tests that showed it does not impact the design of the cabinet. However, while it may not impact the design using T/S parameters, I would suspect that it doesn't hurt to run music through them.

My experience is subjective, but my brand new Beymas did seem to change audibly after a number of hours of use. I did not seem to notice that with my new woofers.
 
Thank you!


Question: One day we will all have 40 Oz. speakers that go from sub 50Hz to 20 K within +/- 2 dB. A pair of them is sitting on my desk right now.

Any pictures? Any info?

Not yet for the general public. I need to get additional IP-protection first and then find a producer.

Since production for your own use is not covered by patents, it is my intention to give in due course all information needed for DIY on this site. Actually, I forgot to mention it in those 40 Oz. active amplification is included :)
 
Not yet for the general public. I need to get additional IP-protection first and then find a producer.

Since production for your own use is not covered by patents, it is my intention to give in due course all information needed for DIY on this site. Actually, I forgot to mention it in those 40 Oz. active amplification is included :)

The ultimate desk top speaker system? Light weight = small speakers and active amplification = perfect desk top or TV speakers.

Thankfully they are not in production yet, I have to get all my other projects done first. The traditional living room now houses the HT setup so I get stuck at a desk in the corner or out in the garage to listen to music. Will we have an idea what it is by the end of the year? :cool:
 
That is true and Vance Dickason also ran tests that showed it does not impact the design of the cabinet. However, while it may not impact the design using T/S parameters, I would suspect that it doesn't hurt to run music through them.

My experience is subjective, but my brand new Beymas did seem to change audibly after a number of hours of use. I did not seem to notice that with my new woofers.

In pro audio it is mandatory to break in new drivers when you replace the blown ones in a complete system. Otherwise they do not match and tuning just doesn't work right.

Having measured new drivers and ones being sold as used, the T/S parameters do not seem to change much on some and a lot on others! Were they wrong to begin? Probably not as they all came from the same manufacturers batch. More likely how much use they got in their first life.
 
The ultimate desk top speaker system? Light weight = small speakers and active amplification = perfect desk top or TV speakers.

Thankfully they are not in production yet, I have to get all my other projects done first. The traditional living room now houses the HT setup so I get stuck at a desk in the corner or out in the garage to listen to music. Will we have an idea what it is by the end of the year? :cool:

I really hope so; before the end of the year would be great. Forgot to mention the prototypes play really loud too, >100 dB at 1 meter, both speakers playing on desk top.

I the meanwhile, I am thinking about opening a post on active filtering without the use of DSP. The good Mr. Linkwitz and his site inspired me to start building active xovers with compensations for driver and enclosure.

Succes with your own projects!
 
In pro audio it is mandatory to break in new drivers when you replace the blown ones in a complete system. Otherwise they do not match and tuning just doesn't work right.

Having measured new drivers and ones being sold as used, the T/S parameters do not seem to change much on some and a lot on others! Were they wrong to begin? Probably not as they all came from the same manufacturers batch. More likely how much use they got in their first life.

In pro audio, drivers may get hot enough over prolonged periods to partly demagnetize the ferrite. This really screws up the T/S parameters.
 
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