Explanation Of Impulse Reverbs
The way impulse reverbs basically work is you send a short blast of white noise out into a room (such as a cathedral or a hallway.... or a bathroom... lol) and you use microphones to record the reverb sound from the room. Then the plugin uses the wave file of the “room sound” and puts that sound onto your track. You can create a very similiar sound to what you would get if you actually recorded in that room.... The quality of the reverb is largely dependent on the quality of the impulse wave file (and there are some great quality impulses out there!). Also, because the impulse programs work off wave files, you can create your own impulses of any room in your house/studio/etc. There are several websites dedicated to creating and sharing impulse responses, like the
Noise Vault Forums and there are a couple example impulses on the SIR website.
The plugin cannot create any reverb sounds without these impulse responses (wave files). So you will need to download some impulse files before you can use it. If you download a bunch of files, it may help to keep them organized by creating different folders for each set of impulses you download instead of putting them all into one folder.... Otherwise you may never be able to tell what what the impulse was from.
The unfortunate drawback to these plugins is they require a lot of processing power. Therefore, they have a large amount of latency (the delay added to the signal due to the time it takes for the plugin to process the signal) and are not able to be used in realtime or by programs without automatic latency compensation. There are fixes for this, the easiest of which is to use a plugin that delays the audio by a specific amount (like the Voxengo
Sample Delay or
Latency Delay), then set the amount to the same number of samples that the impulse reverb delays the signal, and load this plugin onto all of the other tracks in the program. There are other ways to fix it, but overall this ends up being more of a hassle than it's worth.
So unless you have a program that supports automatic latency compensation, then you're much better off using another reverb plugin that doesn't have high latency.
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