Av Acoustics
Are you getting the right Acoustics advice?
The article discusses the importance of using the right equipment, having the right knowledge, and making the right choice for acoustics materials for Acoustic solution. Acoustics a broad subject within itself, Ganesh Gurpur, Managing Director, GENCOM Asia, elaborates specifically on Acoustics for the closed environment. He has several training videos on YouTube discussing similar topics under the title ‘Why Acoustics?’
Ganesh Gurpur, Managing Director, GENCOM Asia, has over 26 years of experience in the field of Acoustics, AV, and Broadcast. He has worked in Audio R&D for almost a decade and has successfully completed major Acoustics Projects using Jocavi Acoustics Panels worldwide from Asia to Africa in the last two decades. GENCOM Asia is one of the leading solution providers for Acoustics, Audio Visual, Broadcast, Cinema, Digital Signage & Film technologies providing services throughout South East Asia and South Asia.
Imagine a person going to a nearby Hospital, when he is sick and assume that the doctor doesn’t have any equipment, but start operating on him with a kitchen knife, would it be acceptable?
The same holds good for your place when you are taking acoustics advice from a contractor. Are they equipped with the right equipment, right knowledge, and right acoustics materials to offer the right Acoustic solution?
Let me guide you through a short journey for about10 minutes in making you understand the basics of Acoustics that is right for your desired environment. Whether it is your Home Studio, TV Studio, Media Room, Auditorium, Cinema, Home Cinema, Lecture Hall, Conference Room or any place, do remember that there is a professional approach for a right acoustics solution, that meets the international standards, good aesthetics, and your budget.
INTRODUCTION
Acoustics is a wide subject with various applications and solutions. Here we would like to narrow down to acoustics for a closed environment.
Acoustics is a less known or ignored subject, usually left in the wrong hands of carpenters. Indeed, they do their best job in ultimately making your place look good for your EYES, but not for your EARS.
Are such installation backed up with professional acoustics measurements? NO! Right?
Do you know that even the so-called Consultants in the market in many countries worldwide, still follow the decades-old traditional method of stuffing the walls and ceiling with glass wool/ rock wool/ wooden studs/ perforated boards/ egg crate foam/ etc., Are these acoustic materials Eco-Friendly or Bio-Degradable or Flame Retardant?
Are such installations backed up with professional acoustics measurements? NO! Right?
ACOUSTICS – TWO ASPECTS
When we talk about Acoustics required for a closed environment, the hitherto adopted method followed by most of the consultants are only ONE. A team of carpenters is engaged with lots of carpentry materials to cover all the exposed surfaces and make it look pleasing to your EYES. As a customer, you never questioned the technical measurement to support their acoustics claim.
There are two aspects of Acoustics that need to be considered.
- Sound Proofing and
- Room Acoustics.
When would you need Sound Proofing?
It is quite simple. If you do not want any outside noise to be heard inside the room or the other way, then SOUND PROOFING is a must. In this case, all the walls, ceiling and at times even the floor need to be covered with Sound Proofing panels. The complexity of the design will be based on how much “dB-difference” you intend to achieve between inside and outside.
In most of the cases, when you have a decent room that doesn’t have the issue of Sound Isolation between inside and outside, then you do not have to spend for soundproofing.
Then what is Room Acoustics?
SSHHH! This is not a topic discussed by many consultants as they do not want to take the trouble of achieving something that they can’t even measure.
Let me give a simple analogy:
When you go to your new flats upon getting your keys along with your wife, you will observe that when you both talk, you observe lots of echoes right? This is because there are more reflected sounds that reach your ears with few microseconds of delays. When this is too high, we call that room as REVERBERANT ROOM.
Let us take the other extreme. Say the room is now fully covered with an absorbent material like foam on all walls, ceiling, etc., which many of the consultants’ advice or you do it yourself. In this case, you are totally avoiding any reflected sound and making it fully absorptive. In this case, the room now has become a DEAD ROOM.
So, neither a Reverberant room nor a Dead room is desired.
Which type of room is the right one? Unfortunately, you cannot guess and do something for the room to sound right for your application. One of the key technical parameters that are used is Reverberation Time, RT60.
Moreover, for Room Acoustics you do not have to cover all the walls and ceiling 100%. Based on the measurement, maybe 40% - 60% of the area only need to be covered. Most of the time you can fix such panels yourself and doesn’t require you to engage a team of carpenters.
CAUTION: Do not get fooled by someone measuring your room only with a Sound Level Meter saying they are providing you an Acoustics Solution. It is like a Doctor saying that he can do Open Heart Surgery using just two kitchen knives.
ACOUSTIC PARAMETERS & MEASUREMENT
For measuring RT60 and few other related acoustic parameters, one needs to use sophisticated Acoustics Equipment capable of measuring - RT60, Real Time Analyser (RTA), FFT, etc., Do you know that there are International Standards for Acoustics and specific measurement methods to follow, in making your Room sound right?
Any material in this world has a specific NRC (Noise Reduction Co-Efficient) value. Any sub-standard acoustic material with an NRC value doesn’t make it a good Acoustic Material. There are a few other parameters to be considered in choosing the right combination of different types of acoustic panels.
ACOUSTIC SIMULATION
There are Acoustic Simulation methods to simulate your room with your existing furniture and the right combination of Acoustics Panels.
Acoustic simulation needs to be done in using different types of below panel types in order to achieve the desired RT60 and other values.
The simulation methods are so close to accurate, that one can achieve the desired RT60 and confirm with acoustic measurement, post installation.
Below is an example of one of the Acoustics Simulation Report:
ACOUSTIC PANELS
Do not be deceived by the Acoustics grade partition boards available from leading brands that are used for Office partitions for large offices. They are not suitable for achieving the Right Acoustics for a closed environment.
A professional Acoustic Panel is usually developed using detailed analysis of material to get a specific set of properties suitable to achieve the desired parameter. Each acoustic panel should have a detailed specification sheet from the manufacturer.
Acoustic panels meant for SOUND PROOFING are specially designed for achieving specific values of Sound Isolation.
Acoustic panels for ROOM ACOUSTICS usually comprises Absorption panels, Diffusor panels, and Bass Traps. The combination of these panels can be determined only using Simulation method studies to arrive at the right count of these 3 types of panels to achieve the desired acoustic parameter.
FINALLY, WHAT IS ACOUSTIC SOLUTION?
Acoustics Solution is not just in using some Acoustic panels.
It is the right solution offered using acoustic panels that are developed using scientific studies and having a detailed technical specification, doing Acoustic simulation, doing on-site measurement – Pre & Post Installation.