When a room sounds good, little treatment is necessary. Recording can be like treasure hunting; or more to the topic, like photography. When all the elements come together art is born. Many recording engineers search for the best space to record in. Some do it by architecture and arrangement; still, others keep everything mobile and try out different venues to see what works best. A majority of recordings contain a mixture of both ambient rooms and treated rooms. Some higher end studios possess both types of room for variety.
Since an ambient space is not something easy to achieve, we’ll concentrate on how to restore an ambient sound to a recording which has been captured in a treated room. A controlled room, as mentioned before, is quite void of natural reflection. The sound is heard directly from the source and not from the walls or other surfaces. This is done to keep phasing and other types of clarity issues out of the recording but it presents an unnatural sound when played back. Many vocalist’s have said, “that doesn’t sound like me” after hearing their voice recorded this way. By adding reverb to a sound we’re able to simulate the echo that a room normally provides. The very first reverb units were very large tension spring plate walls which would be placed next to the performer and the vibration of these plates would be recorded along with the performance. Plate reverb was used even in cinema recordings until technology was able to provide the world with smaller and more powerful units. The classic EMT or Lexicon units are examples of these older units which eventually got replaced by even better units like digital processors and impulse response software. No matter what category of reverb’s sound is preferable to you, the use of this effect is often the same.
One way is to run a sound directly through the unit, which often provides a wet to dry mix knob to allow the mix engineer to dial in the appropriate amount of echo for the track. This method is typical for individual track processing.
Aux send busses are useful across a mixer so that each instrument may be sent in its own amount to the reverb unit which provides an entirely wet version of the mix. This can then be brought back into the mix through an auxiliary return. Several types of reverb can be used at the same time on separate aux busses for room shaping ability. By letting some instruments have more of the shorter reflections while others keep long sustaining tails all-the-while keeping the same reflections throughout the mix, a more natural feel can be reached.