Narrowband Rt – 60-time measurements that are measured in smaller bands of energy will differ greatly depending on the frequency band being measured.ĭetermining the best reverberation times for a room are highly subjective. You can have RT60 times that can be measured in one octave, 1/3 octave, 1/6 octave, etc. RT60 times can also include measurements that can range across the total human hearing band and also at octave bands. The RT60 times that you usually see in the literature, are represented with one number. In fact, it is the time it takes for the direct energy from our sound source within the room to decay at least 60 dB. It is usually helpful to know what range of frequencies are being described by a reverberation time measurement. Typically, the reverb time measured in narrow bands will differ depending on the frequency band being measured. Reverberation time is frequently stated as a single value, however, it can be measured as a wideband signal (20 Hz to 20kHz) or more precisely in narrow bands (one octave, 1/3 octave, 1/6 octave, etc.). RT60 is the time required for reflections of a direct sound to decay 60 dB. It takes into consideration early reflections and “early reflection reverb”. The RT60 time label is the time interval measured of this direct versus reflected dance of energy. Speaking in direct versus reflected energy, it is the interval of time between the direct energy from the source and the last audible reflected wave or ray. Reverberation time is technically the time interval recorded between the original sound with its associated amplitude and the time interval it takes for that sound to not be heard. How long this sound energy takes to get below audible thresholds for human hearing is termed reverb or reverberation times.

These reflections gain in strength and produce echos.

This phenomenon is now called echo and results from reflection accumulation and the material the room surfaces are made of and size of the room. It is more persistent because you can still hear small versions of the original sound source long after that source has quite given off energy. When we have too many reflections that “load” in the room we notice that some reflections when added together cause the sound to be more persistent. We can drastically increase reverberation times through reflections and that increase type of distortion can blur and smear our music and voice. What happens when we get too many reflections within a certain room dimension?. Reflections from the side walls across our listening or monitoring position can cause time delayed sound signatures that we must try and hear clearly through. Primary reflections from side walls interfere with the direct or straight line sound from our loudspeakers. We also know that ref Definition: lections contribute to room modes, SBIE speaker boundary interference effect, comb filtering and lack of the correct amount and type of reflections can contribute to poor room diffusion. Its this balance of direct and reflected energy that we must manage with proper absorption and diffusion treatment. Early reflections strike our ears close to the time signature of the direct sound. They each contain energy that must cause some cumulative effect within our small rooms of today. There are millions of reflections that occur within our small rooms. Each reflection contains energy that can propel it onto the next room boundary surface. Reflections can occur between all walls along with floors and ceilings. What are the reflections? What are early reflections reverb? Reflections are sound energy that strikes any room boundary surface and then strikes another surface and so on until the reflection losses energy and is reduced to below audibility. We have updated this blog content to reflect new advancements in thinking and treating on 11/21/19. What are the differences between early reflections vs reverb (reverberation)? Are reflections part of reverberations? Do high reverberation times in a room mean that there are many reflections that are contributing to the high reverberation times? Are reverberation times within our rooms only influenced by reflections or are there other room distortion that can come into play? Let’s look at the definitions of both reflections and reverberation and see if we can shed some light on the questions raised above

Early reflection definition