Confusion between Attenuation and Intesity change

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SUMMARY

The discussion clarifies the distinction between sound pressure level (SPL) and attenuation in the context of generating artificial insect songs. The user is tasked with achieving a sound level of 70 dB SPL using an attenuator that ranges from -90 dB to 0 dB. It is established that to play the song at 70 dB SPL, the user must measure the SPL and adjust the signal using the attenuator accordingly, rather than simply attenuating the signal by 70 dB. Resources such as the UNSW Physics website provide additional insights into decibel measurement and sound principles.

PREREQUISITES
  • Understanding of sound pressure level (SPL) measurement
  • Familiarity with audio signal processing and amplification
  • Knowledge of decibel (dB) scale and its applications
  • Basic principles of acoustics and sound wave behavior
NEXT STEPS
  • Research how to measure sound pressure level (SPL) accurately
  • Learn about the functionality and application of audio attenuators
  • Explore the relationship between sound intensity and decibel levels
  • Investigate the effects of distance on sound level perception
USEFUL FOR

Researchers in bioacoustics, audio engineers, and anyone involved in sound design or acoustic measurement will benefit from this discussion.

mitbhavsar
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Dear All,
I am basically from Bio background and doing research in Insect Physiology as Phd.
Currently I am given a task to generate artificial insect songs using a software.
I did it with 3 v Noise stimuli(1.5 peak to peak) and fed it to amplifier and I heard it on Amplifier.

So now the confusion starts..
I am also given one attenuator which attenuates with the range from -90 db to 0dB.
Now I am suppose to play my song at 70 dB SPL. Does this mean that I have to attenuate my signal at 70dB.?

I mean playing song at 70 dB SPL and attenuating song by 70dB..Are both same things?
PLease help me..
Thank you in Advance
 
Engineering news on Phys.org
The sound level in the air will depend on the transducer (loudspeaker, etc) you use to play the sound, and the distance between the transducer and the measurement position.

You need to measure the SPL, and use the attenuator to adjust it to 70dB.
 
Adding to AlephZero's measuring of the SPL,

http://www.animations.physics.unsw.edu.au/waves-sound/quantifying/ has some good information that may help.

e.g., these topics are from the What is a decibel? link.

Definition and examples
Sound files to show the size of a decibel
Standard reference levels ("absolute" sound level)
Logarithmic response, psychophysical measures, sones and phons
The filters used for dB(A) and dB(C)
Recording level and decibels (dBV and dBm)
Intensity, radiation and dB
Pressure, intensity and specific impedance
dBi and anisotropic radiation
Example problems using dB for amplifier gain, speaker power, hearing sensitivity etc.
Occupational health and safety and the law
Related pages
What is a logarithm? A brief introduction.
 

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