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My name is John and I'm addicted to measurement software

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JohnPM

JohnPM

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ARTA is a great package, nothing to regret there.
 

Ardacer

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It is. Rew is better. Arta was made by Ivo Mateljan. He lives in a city next to mine. :)
 

Bjorn

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Excellent work John! Much obliged.

I have an important request. Please include an easy way to choose 25 dB/decade aspect ratio of the graph. Why? Read Don's Keele comments below:

"1. This aspect ratio is specified in an international standard IEC263 Dated 1982. Actually three are specified: 10, 25, and 50 dB/decade!

Here are images from the standard:
standard.jpg


2. It prevents the manipulation of response data by changing the aspect ratio of a graph. Plotting response data on a compressed aspect ratio of 50 dB/decade or greater always makes the frequency response look better!

In interests of making comparisons of response data very easy, I always prefer to plot data on a 20 Hz to 20 kHz frequency scale with a 40 dB vertical range (usually 60 to 100 db SPL) and an aspect ratio of 25 dB/decade! I did this for all my Audio Magazine reviews!"

Example of a graph with 65 dB and second with 25 dB decade.

65 dB decade.png


IEC263.jpg
 
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JohnPM

JohnPM

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The graph limits can be set using the Limits button, but there isn't a way to control the aspect ratio of the graph - that's not straightforward given that the window within which the graph is presented is fully resizeable by the user. It might be something I could apply to graph image captures though, I'll look into that.
 

Bjorn

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The graph limits can be set using the Limits button, but there isn't a way to control the aspect ratio of the graph - that's not straightforward given that the window within which the graph is presented is fully resizeable by the user. It might be something I could apply to graph image captures though, I'll look into that.
Thanks John. Contact me if you need the paper that describes the IEC standard.
 

amirm

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I've added an option to the graph capture to apply the IEC263 25 dB/decade aspect ratio, it will be in the next beta release.
Wow, that is fast service!!!
 

DonH56

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Welcome to the World of John and REW... He is pretty amazing.
 

audioBliss

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May 7, 2019
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Sweden
Such an amazing contribution to the audio community! I've used REW for several years now and it has helped me tremendously to understand what speaker positions and acoustical treatment I need in my room. Thank you for also supporting Linux!
 
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