What is a soundproof wall?

What is an Acoustic Wall?

Understanding Basic Acoustic Wall Systems to Trandar Hitech Wall Solutions for Every Space

: An acoustic wall is designed to reduce sound transmission between two spaces by applying principles of mass, decoupling, and sealing. Acoustic wall performance is measured by STC (Sound Transmission Class). The higher the rating, the better the sound insulation. However, STC measures the entire wall system, not just an individual material property. An example of a prefabricated acoustic wall system in Thailand is Trandar Hitech Wall under the TSIS (Trandar Sound Insulation System), which ranges from STC 43 to STC 77. Different application areas, such as bedrooms, meeting rooms, hotels, or studios, require specific STC ratings and tailored system designs.

What is an Acoustic Wall? The Basics

Before diving into specialized solutions, let's understand acoustic walls in simple terms.

An acoustic wall (Soundproof Wall / Sound Insulation Wall) is designed to reduce the amount of sound traveling from one side to the other, whether it's speech, music, machinery noise, or impact sound. There are three core working principles:

1. Add Mass — Materials with higher weight and density reflect sound waves better than thin and lightweight materials.

2. Decoupling — Designing walls with cavities or separating framing studs helps cut off the path through which sound travels via solid structures (Structure-Borne Sound).

3. Complete Sealing — Sound can slip through small gaps much easier than expected. Therefore, joints, wall edges, electrical outlets, or pipe penetrations are all points that must be properly sealed.

An important misconception that many people have is choosing just a single "soundproofing material" and expecting system-wide results. In reality, Sound Transmission Class (STC) is a result of the entire wall system, ranging from surface boards, framing, internal insulation, to joint sealing—not just the property of any single material alone.

What is Trandar Hitech Wall?

Trandar Hitech Wall is a prefabricated acoustic wall system from Trandar Acoustics, designed to meet the demands for sound insulation, fire resistance, thermal insulation, and moisture resistance in a single system without relying on conventional drywall gypsum boards.

This system integrates technology from 3 main components:

• Trandar Zoundboard — A wallboard with embedded Damping Compound that helps absorb sound vibration energy before it passes through.

• Heplar Pro framing — Wall framing systems designed for secure integration with the system and to reduce structural sound transmission.

• dBphon insulation — Acoustic insulation installed within wall cavities, helping to absorb sound traveling through internal air gaps.

When all 3 components are assembled together under the TSIS (Trandar Sound Insulation System), it delivers sound-insulating walls with STC ratings ranging from 43 to 77, covering all application requirements from general privacy to studio-grade acoustic performance.

Which areas should each TSIS system be used for (classified by application)?

The key rule for choosing the right acoustic wall is to start with the space requirements rather than always selecting the highest STC rating, as each area has different acoustic challenges and performance expectations. Below is a guide classified by space usage characteristics.

• Residential and General Areas

General Room, Bedroom, Library The main objective is privacy and undisturbed relaxation from adjacent room noise. An STC 45-50 rating is usually sufficient to make normal conversation from next door barely audible. For libraries where quietness is essential for concentration, interior sound-absorbing panels may be added to reduce reverberation within the room.

• Meeting and Working Area Group

Meeting Room, Office, Classroom, Multipurpose Room The main objective is to prevent meeting content or work discussions from leaking outside the room. The appropriate STC rating depends on information sensitivity. General team meeting rooms are around STC 40-45, while executive offices or sensitive data rooms should consider STC 50-55 and above. For classrooms and multipurpose rooms requiring both privacy and clear speech intelligibility, interior sound absorption should be integrated with soundproof walls rather than relying on sound insulation alone.

• Comprehensive System Area Group

Hotel Hotel acoustic walls represent the most complex application because guest privacy depends on more than just the partition walls. The entire system must be considered, including walls, doors (which should be acoustic doors), ceilings extended to the structural slab to block sound paths from above, as well as high-risk points such as electrical outlets or utility chases. A TSIS rating of STC 55-58 is typically used as the standard for hotel guestroom partitions, combined with Trandar Hitech Ceiling to seal off sound paths above the ceiling.

• Bidirectional Sound Control Area Group

Home Theater, Studio, Music Room These areas require soundproofing walls for two-way noise control simultaneously: preventing outside noise from disturbing viewing/recording, and keeping bass or loud sounds inside from leaking out to disturb neighboring areas. Low-frequency sounds (bass) penetrate walls much more easily than high-frequency sounds, even if the wall already has a high STC rating. Therefore, these areas typically require the highest level of TSIS systems. For example, in an actual studio installation, the TSIS77 d215 system was used, offering up to 77 dB of sound insulation with a wall thickness of only 215 mm.

• Large-scale structure and impact noise areas

Auditorium, Gymnasium / Indoor Stadium These spaces often face issues with both indoor reverberation in large rooms and structure-borne sound, such as jumping noises or balls hitting the floor. Choosing a soundproofing wall system therefore requires special consideration of decoupling, alongside sound-absorbing panels to control indoor reverberation.

• Industrial and machinery areas

Engine Room Engine rooms involve both continuous loud noise and high heat. Choosing a wall system requires looking beyond just the STC rating. A key advantage of Trandar Hitech Wall soundproofing systems that meets this need is fire-retardant, thermal insulation, and moisture-resistant properties within a single system, with STC ratings typically in the high range of TSIS systems to control machinery noise from disturbing nearby areas.

No single soundproofing wall is "the best" for every space, as each has different goals, ranging from bedroom privacy to bass control in home theaters. Trandar Hitech Wall, with TSIS systems covering STC 43-77, is designed to match the specific requirements of each space rather than simply choosing the highest rating.

If you are still unsure which system to start with for your space, chat with the Trandar Acoustics team and share your room details. Our team is happy to help analyze and recommend the most suitable system specifically tailored to your needs.