From dealing with "culprit" ... Deadning [Sound Unit Setting Method]

This series is trying to convey the depth and fun of the car audio by unraveling the rules and precautions in the installation work of car audio products.Last time, I explained what "deadning" is.This time, I will introduce the contents of this work from this time.

"Deadning" has various theories and theory.So the content to be explained in the future is not absolute.I will introduce the matters that are said to be general, but the detailed thinking and way of thinking vary from shop to shop.

Now, as described in the previous article, "deadning" is the work of raising the acoustic condition inside the car door and replacing the door into a speaker.In other words, various problems that occur inside the door are less likely to occur.

By the way, the problem that occurs in the door is the "culprit".It is a "back pressure"."Back pressure" refers to sound energy emitted from the back of the speaker unit.This is in the door, or the outside of the door leaks and transmits, causing badness.

So, in "deadning", first of all, work is done in the place where the effects of this "culprit" extend to the largest.The place is an iron plate on the back of the speaker.A member for countermeasures will be posted here.

There are three parts that are often used.These are "sound absorbing materials", "diffusion materials", and "vibration control materials".

"Sound -sucking material" is a sponge -shaped member, which is aimed at pasting it on an iron plate on the back of the speaker and absorbing "back pressure".In short, it tries to reduce the energy of "back pressure".And the "diffusion material" is made of a material like a light and hard cork, and the surface is uneven.If you put it on the iron plate in the back of the speaker, the energy of the "back pressure" will be scattered, making it difficult for the "back pressure" to bounce to the speaker.

This is because when the "back pressure" bounces to the speaker, it hits the vibration plate of the speaker to inhibit the movement of the diaphragm.The "diffusion material" has the effect of relieving the stress.In addition, "sound absorbing material" also plays a role in reducing the bounce back of "back pressure".

The "vibration -controlled material" is made of butyl rubber and asphalt -based materials on the aluminum sheet, and the resonance of the iron plate is suppressed by placing it on the iron plate on the back of the speaker.The iron plate also makes a few sounds if vibrated.The sound muddy the sound emitted from the front side of the speaker.However, if you put a "vibration -controlled material", you can suppress the sound of iron plates.

That's it for this time.Next time, I will explain the contents of the work that will be performed later.looking forward to.