Well done Richard. Reminds me of being at college, using dB to define filter slopes. I can't do that now!

I may have actually learnt something tonight. let's see if I remember it in the morning.

Thank you, your video showed me a couple of new valuable perspectives on dBs! Only so far ALL videos about decibels continue to be misleading because their authors choose "the correct subject for decibel" - in this case "Power". At least you mentioned in the end that dBs for Voltage are quite different. But what if I come here to learn about dB SPL? Or perhaps more exotic dBFS or something even more rare - different explanations talk about one but not another, and then we want to learn how amplifier power relates to SPL... :)

@richardlangner

7 ай бұрын

Decibels ALWAYS refer to power! SPL transducers output a voltage, and the video shows how to work out power from measuring this voltage.

@SDX9000

7 ай бұрын

@@richardlangner I agree that dB SPL is comparable to dB Voltage, only it is not a all obvious for me or people who are looking for explanations of decibels. If you say decibels are ALWAYS referring to power then are you implying that calculation with dB SPL or dB Voltage can not be done without recalculation into power? It is a nice lifehack, only not intuitive for someone who only uses dB in the context of SPL. :)

@richardlangner

7 ай бұрын

Decibels are relative power. Remember that power is voltage V x V x I (voltage squared times current). To square a number using logs, you simply multiply by 2, hence we use 20 log instead of 10 log when working with voltage. If your setup doesn't change between measurements you can use voltage measurements and calibrate the SPL scale using 20 log. No need to recalculate power. I'm glad to are interested enough to ask the question - I hope I have answered it.

@SDX9000

7 ай бұрын

@@richardlangner According to this approach: sengpielaudio.com/calculator-db-data.htm are two types of quantities expressed in dB. So depending on perspective, dB is not always about power. But I certainly like your approach - I wrote down for myself your explanation that "dB value of Voltage multiplier is exactly 2x (double) the dB value of Power." - haven't seen it this clearly before. I do have difficulty finding reference for "power = voltage squared times current" - this may be one more of the confusing parts about decibels, when in other contexts "P = U x I".

Thank you

@richardlangner

Жыл бұрын

You're welcome

where is the simple bit?

@eternaldoorman5228

11 ай бұрын

🤣