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What is a decibel? A Video Tutorial

dorirod

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Thanks for the video Amir! As an uninitiated, I appreciate all the laymen info.

Ray did a nice thing here . The Shoutometer | Audio Science Review (ASR) Forum It has some limits but the gist of it is to give perspective (air as medium probably wont work at these distances it will all be randomized anyway )

"Here's my handy ballpark reference going the other direction, when trying to "imagine" sound that is "softer" than another by some number of decibels."

I don't know if I can trust that guide after watching this video :)

P.S. When Walken's equipment doesn't get loud enough, does he ask for more 'bels?
 
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617

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Thanks for the video Amir! As an uninitiated, I appreciate all the laymen info.



"Here's my handy ballpark reference going the other direction, when trying to "imagine" sound that is "softer" than another by some number of decibels."

I don't know if I can trust that guide after watching this video :)

P.S. When Walken's equipment doesn't get loud enough, does he ask for more 'bels?
I recently made a visual illustration of the shoutometer, see attached image.

Most people really have no intuition about how damn quiet even -60db below a reference level is.
 

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Vovgan

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Chief, after watching your video the question remains unanswered: what is a decibel? And practically - how bad is a second harmonic hitting -90 dB?
 

617

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amirm

amirm

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Cool seeing the AP in action.
Yeh, the machine is camera shy. I promised it half of my proceeds from the video and he agreed to a few teasers like this.
 

Trouble Maker

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I think a critical thing to understand is SINAD is 'area under the curve', not just a peak. Some people might see a bunch of peaks just below let's say 120dB and think SINAD should be 12xdB but the SINAD is 11xdB or 10xdB and could be confused. Or even more critical to this example the AP loopback which has nothing above ~135dB but has SINAD of 122 Decibels. ;)

Thanks for the videos!
 

MetalDaze

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Even without all the screen grabs, really nice video! Clean & well articulated. The audio is smooth and clear :cool:

This is a great learning video & a good way to help less technical people grasp the reviews. Loans a lot of further credibility towards yourself & the forum.

Cheers!
 

Thomas savage

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FYI I used the wrong screen capture method which didn't catch the pop up dialogs. Was too lazy and unmotivated to re-record the whole thing to fix it. :) Will make sure that doesn't happen in the future videos.
Yes ! Yes yes this is what we need ..

Now what about ( how to make the most of amazon eq on android platforms ) .

" Learning from the beginning and why that should be fun "

If we want to effect change we need a focused and armed consumer.
 

Ajax

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I had requests to do tutorials on YouTube so I thought I do a quick one on Decibel. It is actually not what you think in that I don't really explain it. :) But rather, show the proper way and reasoning in a live demo using my Audio Precision software. So even though you may know what a dB is, you may want to watch the video to see the AP in action.


Hey Amir,

This type of "instruction" video, and your recent ones that dealt with unnecessary products, such as expensive cables, decrapifiers etc, is exactly what our hobby needs.

There are many that argue"what's the problem", people should be allowed to spend their money as they wish, no one's killing babies. However, people are being misled and spending a lot of money on gear that provides no benefit. The problem is that our hobby is viewed by the outside world as being stupidly expensive and full of crackpots causing our younger people to being turned off from getting good gear.

We all know that you can purchase an excellent system for a small room for less than US$500. All you need is wifi, a smart phone or computer, connected to gear such as a raspberry pi streamer, topping e30 DAC & JBL 305 or ADAM TV5 active speakers. I would argue this is in reach of most of the population except those in financial difficulties. Add a Tidal subscription for content and you are good to go.

The real problem is that there is so much BS being propagated that only those that frequent sites such as this have the knowledge to put together such a system.

It is really really really important that people in our community with a subjective bent understand the power of bias and how it affects their decision making. Whether it be expectation bias through mis leading commentary or their brain playing tricks on them when they listen "harder" to new gear.

This nonsense has gone on for far too long and you, together with Archimago, Mark Waldrup (Dr AIX), John Siau from Benchmark Media and a small number of others are leading the fight back to rational thinking using measurements and basic maths.

Thank you and well done!
 

Dzhaughn

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You should change the title to "What is a dB?" I hear that's cooler than saying "decibel."

I guess good DACS have SINAD of more than a decabel at 10 hectohertz. That's 1 full hectodB.
 

LTig

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You mean the bit where he says to use dB and not decibel? Unlike in the video title and description.
Yes - to say dB instead of decibel to fake the impression that one knows more than one really does.:D:D:D
 
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