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The EchoErase© Silent Stand

Create a do-it-yourself EchoErase Silent Stand and position it in a room with these instructions.

To start, you need multi-absorbers. Why?

For every octave lower in pitch sound goes, sound absorbing material needs to double in thickness to absorb it—the lower frequencies of the human voice require material nearly two feet thick to be effective.

These thicker materials (like pillows) absorb ALL frequencies, down to the lowest frequency they are thick enough to absorb. Materials 18″ thick or greater (like three stacked pillows) are called multi-absorbers.

You need multi-absorbers behind your mic to absorb some of your voice before it can echo, and more behind your head where the mic is “listening”.

#1 Error: Thinking “I’ll figure out where to put my script later”. You’ll need to see your gain indicator next to your script—commonly, the lights on your preamp. So design your studio around where the mic and preamp go—ideally, next to each other on a copy stand.

Most of the best mics for voiceover are directional. These mics create their directionality and proximity effect (you sound warmer when you are closer) by utilizing sound signals from the back of the microphone.

Therefore, if you put baffling material on the back of your microphone—and you should—you may want to leave 1/2-1 inch of room for sound to reach the back of the microphone directly. Don’t leave much more room, though! For side-address microphone designs, you can wrap two loops of plastic tubing around the mic to leave an air gap on the back.

The main thing you will notice if having material covering the back of the mic with no air space is you will sound less “boomy” when getting very close, which can be desirable. Absorbing some of the sound of your voice and absorbing some of the echoes before they reach the mic is beneficial—and material on the back of the mic is the best way to do that, because it brings sound absorbing material very close to your mouth (your voice is the primary source of undesirable reverb and flutter).

“Directional” means rejecting some off-axis sound (stay in front of the mic. Proximity effect is a kind of side effect of directionality that decreases low-frequency rejection when you get closer, compared to being farther away.

Directional polar patterns (cardiod, supercardioid, hypercardioid or figure-8), manipulate the phase differences between the front and back of the diaphragm, either through vents on the back (common on single-diaphragm mics), or in a two-or more diaphragm design, by combining the signals from a front diaphragm with a back diaphragm out-of-phase.

The most important thing you can do to improve your home studio acoustic baffling: Absorb your voice before it can echo. Absorb as close to the mic as you can. You need to absorb the sound of your voice because of two types of echoes: flutter and room modes.

The problem with room mode echoes

The smaller the space, the more room mode echoes become a problem. Click below to hear a voice recorded and played back in a room, then played back and re-recorded in the room over and over until the words become unintelligible, replaced by the characteristic frequencies (room modes) of the room itself. This is demonstration of how sound we hear can mask the source of sound in inside spaces with parallel hard surfaces (e.g. floor and ceiling).

YouTube Video Example

BEST CLOSET TYPES:

Type 1A or 1B: Wide or double-door reach-in closet

Type 2: Typical walk-in closet

Type 3: Walk-in closet larger than 7’x7′

PROBLEM DOOR TYPES:

Type 4: Narrow door, reach-in closet

Type 5: Corner door, walk-in closet

Click any picture to enlarge:

The ideal space is deep enough that you can place the mic directly under the door frame, and the doors are wide enough that you can stand inside and wave your arms around a bit without hitting things. Some double door reach-in closets are too shallow, and so you can’t back in as far as is ideal. This means the mic will pick up echoes (“reflections”) from the wall around the outside of the door, and you will benefit from absorbing some of those echoes with pillows around the door frame, as shown below.

Type 1A: REACH-in Wide Closet

Stand nearly under door frame:

Type 2: WALK-in Closet, regular door

Stand inside, pillow inside door frame:

Type 4: Shallow Closet • Narrow Door

Stand outside, pillows around door:

 

Type 1B: Shallow Closet • Wide Doors

Stand outside. (1) Remove doors, or

(2) Hang absorbent material on doors:

Pillows on
Copy Stand:

Convert a second copy stand into a stand for the pillows (vs hanging or PVC stand).
Click any picture to enlarge:

Pillows tilted back to make seeing over easier:

Overstack pillows before tying together:

• Stabilize stand from tilting with duct tape on back
• Be sure to be able to move hands around underneath closest edge
• Do not rely on built-in tightening adjustment

Pillows on
PVC Stand:

Hang/Mount Pillows:

Pop Filter On Arm

Click any picture to enlarge: