You are one step away from taking part in the most inspiring community of musicians and songwriters.

Modules

Area Menu

New Articles
Are amphitheatres the original high pass filters? Graeme Young takes a look at amphitheatres, psycho-acoustics and digital signal processing to complete the link from ancient Greek ampitheaters thrrough to modern day recording and live performance. By Graeme Young
Recording a professional quality CD has always been the domain of recording studios. But the times they are a changing with professional quality recording becoming an affordable option within your own home. Just how affordable is it to achieve professional results? By Cheryl Hodge
Temperament affects the tuning of musical instruments. This article provides some background information on temperament and intonation and presents a formula used in the calculation of note positions. By Graeme Young
This article is an in-depth review of AmpliTube 3, from IK Multimedia. Building on the reputation of AmpliTube 2 this simulated amplifier environment modeling software has a lot to live up to. By John Moxey
Review of T-RackS 3 Deluxe Edition from IK MultiMedia By John Moxey

By John Moxey

Reverb - Background

Everything we hear is a combination of the sound travelling directly from the source to our ears and reflections of the sound from surfaces and objects in our environment. This means that a reflected wave has to travel further to reach our ears and so it arrives at our ears later than the direct sound, and from a different direction. Normally our brains decipher this information to obtain information about our environment, and our position within that environment.

An Anechoic Chamber is a special room that produces no reflections, due to both architectural design and the use of special acoustically absorbant materials. If you stand in an anechoic chamber and clap, the lack of reverb is strange, and somewhat unsettling. The human brain is not used to dealing with a reflectionless room. The lack of information about our environment is an uncomfortable sensation, especially when our eyes are telling the brain that our ears should be detecting some information.

Reverb, or more formally Reverberation, cannot be removed from a signal. So, unless you are deliberately trying to capture the natural sound of a particular room or hall on the recording, it is common for sound engineers to use close miking techniques to minimise the reflected sound and maximise the direct sound during recording. This allows the engineer to manage the reverb on the track by artificially applying reverb using either an analogue or digital effects unit.

Each environment has a characteristic reverb. For example a small room has a short reverb time, so much so that it is not always very noticeable. Conversely, a large hall has a long reverb time as it will take a significantly longer time for the reflections to die away. The absorbtion of the walls, floor and ceiling will colour the reverb as the absorbtion of different surfaces varies with frequency.

When a sound is emitted within a room, the reverb will be delayed by the time to the first reflected wave. This time is called the Pre-Delay. Next the reverb enters a phase called Early Reflections, as the first and clearest reflections of the initial sound reach the listener. Lastly the reverb enters a phase of Dense Reflections as the amplitude of the building number of reflections fades away as the energy of the sound is absorbed by the surface materials of the environment.

Each time the sound is reflected the surface that it collides with will absorb some of the sound energy, thus reducing the amplitude. But the frequency response of different surface materials means that each material will absorb a different amount of sound energy at different frequencies.

As mentioned, effects processors are used to artifically apply reverb to a source signal. These effects processors can be either analogue or digital effects units. Plate or Spring reverbs are commonly used in both domains, although both are simulated in the digital domain.

Discuss this article in our Music Forum.

About John Moxey

Author - John Moxey

John Moxey started Songstuff in 2000 and is an active songwriter and musician as well as a regular Songstuff author of music and music technology related articles and member of the site crew.

John started playing his first instrument (piano) in 1971, and has been writing songs since 1979. He began playing his now main instrument, the guitar, in 1982. In 1986 he finished training as a studio engineer and in 1997 obtained an Honours Degree in Electronics and Music from the University of Glasgow.

John now plays several other instruments including mandolin, violin, bagpipes, didgeridoo, bodhran, and vocals.

John has a broad range of performance experience from choirs and orchestras to pipe bands. He has sung for, played in and written for various bands, and produced songs across a number of genres.

John's Blog

John Moxey - Full Site Crew Profile

John Moxey Home Page

Contact John Moxey

Related Articles By This Author

AmpliTube 3 from IK Multimedia
T-RackS 3 Deluxe Edition
Ocean Way Drums from Sonic Reality
T-RackS 3 Standard Edition
AmpliTube Fender Review
AmpliTube Jimi Hendrix Review
Midi Sync
Music Note Fundamental Frequencies
Midi Message Format
Standard Filter Types
EQ Frequencies
Reverb
The Midi Interface
Home Recording
Noise Gates and Expanders
Equalization / Equalisation (EQ)
Compression