Can portable vocal booth block outside noise? This video show how efficient our contestants in reducing noise from a vacuum cleaner:
We made this side by side comparative review of the major portable vocal booths on the market: VOMO, ISOVOX and PortBooth Pro from Harlan Hogan.
The sound source is Vacuum Cleaner.
The measurements done by sound meter and also by direct recording by microphone and then comparing the waveform from each recording side by side.
All tests were done in triplicates in soundproof and acoustically treated studio. The results are:
Even though the portable vocal booth are not designed to be soundproof, because they are partially open. Still they did reduce the outside noise.
VOMO and ISOVOX performed very close and did pretty well for a portable vocal booth. Both reduced the outside noise by about 7-8 dB. There was difference in the frequency distribution: Isovox had a tighter amplitude level and VOMO had a little wider spread within the same overall parameters. We think this is related to the material the booths are made of: ISOVOX has rigid solid walls and therefore probably reflects as well as absorbs a range of frequencies. VOMO has only absorption layer, so it would absorb more of the high frequency and “let in” more of the low frequencies. This is why the sound waveform was more rugged, than for ISOVOX.
Portabooth Pro was completely ineffective in reducing outside noise. On the contrary the noise was about 2dB higher in the booth compare to the control. You can still hear the difference, that is probably because Acoustic foam was absorbing some of the high frequencies.
Why would the dB level in the Portabooth test was higher than the control?
Assuming that the Noise source was consistent in all tests, it is possible that the hard shell of the Portabooth that is actually has concave shape may reflect the sound waves and focus them on the microphone.
VOMO – your Portable Voice Over Recording Studio provides ample interior space for audio recording voice over or singing. Allows you to work with your favorite microphone in your favorite location.