reverberation tricks at music mastering servicesWhen creating quality commercial sound, professional engineers and producers often use at least one of the four techniques described in this article or their different combinations. In spite of the obviousness of all these tricks, hardly anybody can guess of their existence and use them in their mixes. And how wrong they are!
1. Double reverberation
This approach doesn’t often take place in pop music ixing mastering online in comparison with traditional use of the reverberation connected through the send processing technique. The gist of the send processing is the creation of a separate AUX channel with an effect. You can apply a dosed audio signal to this channel from the basic one which is being processed.
In this case the reverberator is connected to the insert of the send processing channel. The correlation of the wet and dry signals is adjusted in its settings in the way that there is only the wet signal in the send output and it isn’t mixed with the original signal.
The gist of double reverberation is sending the signal already partly processed by reverberation on the send processing channel. For this reason, the reverberator with very short attenuation time (up to 1 second) is placed into the insert of the processing signal. Afterwards according to the classic schedule the audio track is sent on the send processing channel with the reverberator which, for instance, creates a room effect.
2. Viral reverberation
This effect was named in this way as the gist of its operation looks like viral expansion. What does it after all consist of? Suppose, we have some connected tracks, for instance, bass, snare drum and overhead microphone tracks which pick up sounds of all hats and the common sound of a drum kit.
After we have sent, for example, only a snare drum track to the send processing reverberation, at a certain correlation level of dry and wet signals we start hearing the reverberation on the other audio tracks as well. On having sent only one channel to the send processing, in this way we enrich the entire kit with a volume of some room. This trick is based on psychoacoustic peculiarities of our perception.
When damping the drum track processed by a reverberator, we deprive the other instruments which this viral reverberation has affected of the supposed volume as well. 

reverberation tricks at songs mastering3. Spatial arrangement
Professional engineers use reverberation not only to give the volume to a sound, but also to move it off or nearer to a listener. A clumsy example of it is the use of some sort of scaling preset like “cave”. The long fading tail of the reverberation creates an illusion of the distance of the sound processed by this reverberation.
It goes without saying that such processing can significantly mud a mix as it takes a good deal of space at vocal mixing tips. That’s why it should be used only in key points and in limited quantity. 
Thanks to the reverberation effect you can move the sound away and closer with the help of attenuation of high frequency and pre-delay time settings. 
When high frequency attenuation happens fast, the sound seems to be farther as the air absorbs high frequencies a lot faster than low and middle. If you don’t suppress high frequencies, sound source distance effect won’t happen, and it can be heard just as a special effect.
Pre-delay time is the time which lasts from the burst of a clean sound to the beginning of the similar burst processed by a reverberator. Otherwise speaking, it is one of the factors which on mixing build up the distance to the imaginary surface reflecting the sound.
Consequently, when pre-delay time lasts long, the processed sound seems to be in a volume space but at the same time closer to a listener. When the pre-delay time is little or zero, the sound seems to be far in a volume space. 
4. Processed reverberation
All the manipulations with the sound processed by reverberation belong to great deal of tricks of this kind.
One of the most remarkable effects is reversed reverberation. To get it, it is necessary to reverse the original sound, to process it with the reverberation picked up beforehand and reverse it backwards. After such processing the reverb tail won’t fade away after the burst of a sound, but, on the contrary, it will keep rising before it.
Other techniques include reverberated signal processed by different effects. For instance, you can connect a phaser or an octaver to the insert of the send processing channel. Therefore, professionals get a clear original sound and the reverb tail processed by special effects afterwards.
On the whole, there are a vast number of techniques for use of reverberation. Only 4 methods of them have been listed out in this article. I advise you to keep experimenting with reverberation constantly to find permanently new and new kinds which you can get as a result of effect processing.