Measuring sound levels

[Martin Matěj]

Hello, I would like to ask which curve (dB-A, dB-B, dB-C or dB-Z) should I use to make a consistent measure of noises like elevator, high heel walking, Music band playing.

All the sounds will be happening behind old door and then behind new door.

I will be measuring through iphone app db meter pro.

Thanks

[BTM_Pix]

It depends what the purpose of the testing is and the source.

The 'A' weighting is the most commonly used as it is shaped by typical human hearing responses, hence why it is the one used in assessing risk of damage to hearing.

The 'C' weighting includes the lower frequencies not addressed in the 'A' weighting and a flatter response between 80Hz-3kHz to better reflect human hearing becoming more linear at louder sounds levels.

The 'Z' weighting is flat across all frequencies.

Due to the ubiquity of the 'A' weighting it will be a more universally accepted/relatable measurement (when the local authorities come round to measure noise they will use 'A' weighting for example) but 'C' might be more appropriate if the sound source is very loud or contains a lot of low frequency content.

So, as a very simplistic answer, if the purpose of this new door is to reduce the annoying noise coming from your musician neighbour across the hallway practising for his next gig, then if he's playing a xylophone I'd measure its effectiveness using 'A' weighted whereas using 'C' weighted would give you a better indication if he's a bass player.

https://pulsarinstruments.com/en/post/understanding-a-c-z-noise-frequency-weightings