Axiom Home Page Forums General Discussion Advice from Axiom Owners The science behind speaker break-in

When people talk about speaker break-in, they're referring to the actual speaker drivers physically changing over a period of time. I completely believe you when you say what you heard was NOT in your head. After all, you don't get used to rattling in the sense that you just can't hear it after a while.

However, this does not necessarily mean that the drivers physically changed, as the phenomenon of break-in requires. What probably happened is that over the course of six weeks, the net effect of vibration from the road and from using the speakers resulted in them being better coupled to the car. I have a feeling if you manually tightened the speakers in their mounts on day one you might have had better sound right away.

This is just my own theory, but since I reject the notion of speaker break-in, there must be a more logical (and provable) cause to the change you experienced.

agreed.. get you a phillips head and tighten the screws on the grills, and in the trunk on the speaker.. it will probably take care of the rattle you are hearing.

peter- i have been watching your child getting drunk now for a week.. where are the pics of him hitting on the ugly girls, and throwing up??

bigjohn

LOL. It'll be a few years yet. Right now, he's just busy working on his charm.

i have always thought that the first person to invent a nipple to fit on the end of a beer bottle would be a very rich man!!



bigjohn

If the reason is really about the screws not tightened enough, I don't think it will be fixed automatically after 6 weeks of driving. Vibration from the road will only make it worse by further loosen the screws.

I do not disagree to the brain "breaking-in" thoery and that makes perfect sense. However, that does not mean that audio equipments do not break in.

I did a several break-in test before. After I did an initial listening, I let the equipment run for a long time (more than 100 hours) without listening at all. Some components like preamp, power amp, and speakers do have a more significant break-in effect. Others like cables and interconnect are less significant, if any.

And I just tested a McIntosh MC252 poweramp last week. After the amplifier was first taken out of the box, bass was very weak and sometimes not noticeable. After powering up for 1 full week (sourcing from CD, and I was away from that house =), the bass came back.

Ok let's talk about science now. It is very obvious that mechanical parts require break-in (e.g. automobile). Most speakers produce sound by moving physical objects like cones. Characteristic of the substance will change after a long period of moving, and exposure to different environment. On the other hand, electical components like transistors and capacitors also take time to reach their optimal operational form.

Correct me if I am wrong.

Again, I'd like to know why these changes that you describe stop after it reaches what one might describe as the ideal point. Why do the cones not continue to become looser, providing a less satisfying experience, why don't the transistors and capacitors start degrading immediately to the point where you would hear the difference? Why don't computers (lots of transistors/capacitors) need/experience break in?

{tone of voice is inquisitive, not challenging or sarcastic}

Let me preface this by saying that I don't personally believe in break in.

However, speaker break in I could be led to believe in, if I were shown conclusive evidence. I think it's at least plausible that the drivers and driver mounts experience some structural alteration from prolonged movement. If you take a piece of printer paper, crinkle it into a tight ball and then carefully flatten it, the fibers are loosened. If you do this 20 times or more, you can end up with a sheet of paper that feels a lot more like a tissue than printer paper. Also, the degree to which the paper softens lessens with each succesive crumpling and flattening. So it's plausible that the physical degradation of a component follows some curve and results at a "steady state" of sorts beyond which that component will not degrade measurably.

On the side of purely electrical component break-in (amps, etc...) I don't think break in makes any sense what-so-ever. It is certainly true that the underlying molecular structure of metal is afected by heating and cooling cycles, as well as maintaining prolonged states at certain temperatures. But all of the temperatures at which such changes occur are well above the operating temperature of any standard household electronic device. Any audible change in an amplifier could only result from some significant inherent property change in one of its components.

The car analogy doesn't work because the physics involved in cars and speakers are fundamentally different. The parts of a car that break in mechanically do so primarily because of friction -- they physically rub against each other. A speaker driver does not experience that kind of friction. The driver cone flexes, sure, but it's not rubbing against anything.

In fact I did not say the changes will stop after any point. A friend of mine and myself can hear that the sound from our systems keeps changing over time.

At the end all components will get old and will definitely provide "a less satisfying experience". Old speakers need to be re-coned as rubber gets old and fragile. The attributes of resistors and capacitors will also change over a long time.

It's interesting to see how many people are actually against the break in theory. I think the most scientific way is to verify it yourself.


BTW, I bought my first computer more than 10 years ago. At that time the computer technician did help me breaking it in by powering it on for 2 days straight. =) I couldn't tell the difference by then anyway.

Oh, certainly surrounds rot, etc, but I think that's a biological or chemical process as opposed to a physical one.

I think the most scientific way is to have it tested independantly by separate laboratories.