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Hi,
My friend Rodrigo Lopes did a lot of research, testing and developed a new Microphone Recording Technique.

It is the Lopes Stero Micing Technique.

I don't know if it is allowed to post a download link here, but we would like to spread and share this subject worlwide.

RapidShare: Easy Filehosting

You may contact him for doubts and suggestions.

Nice 2009, to all!

http://rapidshare.com/files/175023095/Lopes_Stereo_Micing .pdf.html

Comments

Alécio Costa Fri, 12/19/2008 - 19:47

Sure!

It is a 90kb pdf file.

New: Lopes Stereo Miking Technique
The Lopes Stereo Miking technique captures a mixture of both fields, near and far, with a well balanced combination of the direct and the reflected sound.

Of course, a good sounding room is necessary to make it work correctly. It tries to minimize the problems coming from phase differences and the lack of deffinition in the center image, when playing the recording back through a pair of monitors.

In the Lopes Stereo Technique, the distance between the outer edges of the sound source (d) is measured, and then divided by 2 . In the example below, we have a drum set with snare, Hi Hat, 2 toms, 1 Floor Tom and 2 cymbals.

(continues)

anonymous Sat, 12/20/2008 - 11:15

First off, that is some great research, and logical thinking. I like what you are trying to do. I do have some questions as some things are a little unclear to me. People who are willing to experiment and find new ways to do things keep recording alive.

Just some critical analysis on what you are saying. It seems that you have put a lot of work into this, so please correct my logical errors when reading this.

1. When talking about the Mid Side pair, you say that the sonic image is “less defined” can you elaborate on that?

2. On spaced pairs you say that “They tend to have a hole in the sonic image”

If an AB pair is setup correctly there is not a hole in the image. If the microphones are four feet apart for every three feet from the source then the response is completely even across the front. For example, if you have a choir that spans 20 feet from left to right, and the microphones are placed at either end 15 feet in front of the front row, the front row will have a even response from all vocalists. To capture the back rows evenly raise the microphones keeping the distance to the front row mouths, and aim them at the back row. This will give an even response of the entire ensemble. I have done the math, and used this in practice. It works.

3. “The 3 to 1 proportion between the two microphones and the nearest part of the sound source is maintained, minimizing the problems caused by phase cancellation” I don't follow you here. If there is a difference in distance there will be phase cancellation. The frequency at which it will occur is nS/d where “S” is the speed of sound, “d” is the distance, and “n” is an odd number.

4. “This causes the center to be captured at a 6dB loss compared to the edge”
Sound level dissipates as 1/d^2,

left sound center right sound
Left 1 1/4 1/9

Right 1/9 1/4 1

total 1 1/9 1/2 1 1/9

The center is just less than half the volume of the sides. So this is inferior to a regular AB or XY setup? The center of the source normally has the focal point. In your example this would be the kick and snare. These are half the volume of the auxiliary sound?

Because the microphones are facing each other I would expect to see more phase cancellation. Any reflected sound from a side wall will be traveling in opposite directions relative to the diaphragms of the microphones.