Sound-Absorbing Wool and Vibration-Damping Felt (Sound-Absorbing and Vibration-Damping Materials)

As mentioned in other articles, the white wool and felt in the images are products made from recycled materials, while the black felt is a product processed from virgin polyester fibers.

The common names used by our supplier manufacturers are PET wool for the sound-absorbing wool and high-density PET felt for the white felt. The black felt is distinguished as special felt.
All products are made from safe materials from which no chemical volatile emissions are detected.
Of course, they meet the F☆☆☆☆ standard.

I have had users with pre-existing conditions such as allergies, atopic dermatitis, and asthma use these products, and there have never been any problems.
*I personally suffer from allergic dermatitis, and not only do I keep samples in my room, such as on my work desk, but I have also been tracking aging and degradation by installing them myself in my home office for about 30 years. There have been no issues at all.

Because these products are made of materials that do not produce dust when cut and do not cause itching, they are popular not only with DIY enthusiasts but also with professional contractors on-site.
I have stated in other articles that sound-absorbing materials, vibration-damping materials, wood, and wood products are often overlooked in the acoustic and soundproofing design of wooden music rooms.
In this article, I have focused on and further examined PET wool and felt, which are the primary products used at sites managed by soundproofing professionals.

Differences between PET felt and special felt

There is almost no difference in performance as a vibration-damping material. The only differences are color and unit price.
Although both are classified as "vibration-damping felt" by soundproofing professionals, PET felt is cheaper, so contractors overwhelmingly choose PET felt.
The problem is that among the manufacturers producing PET felt, there is only one company that can supply it at a low price, so the supply is unstable.
For this reason, it is only produced at the factory once a month, so if stock runs out, delivery times are significantly delayed. Furthermore, only one company for PET felt and one company for special felt have proven track records of practical use as vibration-damping materials.
Both companies are contracted manufacturers for soundproofing professionals.

Also, PET felt comes in a size of 6mm thick by 950mm x 1850mm, while special felt comes in 5mm and 7mm thicknesses and is delivered in box units at about 1/4 the size of PET felt. The installation procedures for both are the same.
By the way, products from other manufacturers were excluded after testing them when we first started because their vibration-damping performance against impact noise was low. *I have looked for products from other manufacturers for about 30 years, but I could not obtain the performance I was looking for, and the unit prices were quite high, so I could not adopt them.

Differences between PET wool and glass wool/rock wool

PET wool (sound-absorbing wool) does not produce dust when cut, whereas glass wool and rock wool produce dust and cause itching.
People with pre-existing conditions such as allergies or asthma cannot use them.
This is a major difference. If you are concerned about the health of users and residents, it is safer to choose PET wool without hesitation.

The sound absorption rate of PET wool is higher than that of glass wool in most frequency bands, but rock wool is better in the high-frequency range.
For this reason, the effect in the high-frequency range is covered by the combined use of sound insulation materials, so there is no problem with the overall soundproofing performance in wooden soundproof rooms.

Also, a feature of PET wool is that it does not degrade for over 30 years.
*The service life of glass wool and rock wool is generally about 15 to 20 years. Their sound-absorbing performance decreases over time.

This article is also a response to those who have the same pre-existing conditions as I do or to those who prioritize health concerns. I hope you find it helpful.
*The following image shows a wooden soundproof music room with sound-absorbing wool (PET wool) installed in the soundproof walls and under the floor. Vibration-damping felt (high-density PET felt) is used in the floor's soundproofing structure.