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Is Audio Science Review going about it all wrong? Or partly wrong? Or all right?

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But my point is that distortion around 1% is audible and still does matter.
Allot the stuff your talking that are 1% are only that at 90 to 100db and same for much higher stuff. The Grado SR225e is like 5% in the treble yet nobody notices which is why i doubt the ER4XR is gimped by being 1% since allot don't even notice that, By my comparisons logic the ER4SR and other 0.2 - 0.6% headphones/speakers there already distortion free. I think its bit sillly that a poor measuring gear should be ignored because they pass a line that allot can't even tell or even back up without being subjective.

Also the ER4XR/SR is like <0.1% at 90 and 0.5% at 100db on treble area.
 

JohnYang1997

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When it comes to headphones, neutral is in the ear/brain (or HRTF) of the beholder.
It's true but unless they actually compared to flat studio monitors in treated room they are in the dark. The preference is trained/ affected, not all if have anything to do with hrtf difference.
 
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Funny how you and another have to ignore that allot the stuff is done at 90 - 100db, That grado is has peaks that reach 1.2% at 90db and 4.5% at 100db. A ER4XR is 0.7% at 90db, 1% at 100db.

At normal volumes that a grado is 0.55% while the ER4XR is 0.35%, Not to mention there a thing THD masking were few are cancelled out making it inaudible or the gear is revealing details that go noticed flaws included.

Good speakers and headphones should be below 1% in this range.
Yeah because the human ear is such a valuable tool, When its so easily fooled by the silliest things like warmth can induced by some distortion. Yet all those speakers and headphones can cleanly render a bass guitar which on its own is just 23% THD. I had the ER4XR before the SR i never once though ew 0.7 - 1% when listening to it, in fact it was cleaner than anything i had before it.

The ER4S had 0.6% THD yet enjoyed 20+ years of fame and heck that album you linked was probably mixed and mastered on a high THD speaker.
 

MRC01

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It's disingenuous to describe the sound of a bass guitar as 23% THD. If you mean the sum of all harmonics has 23% of the amplitude of the fundamental (12.8 dB lower), then it's incorrect to call it distortion. Those harmonics aren't distortion, they're the timbre of the instrument. Some acoustic instruments (like flute in its bottom octave) can have the 1st harmonic stronger than the fundamental. Shall we call it more than 100% distortion? Of course not. It is the natural live sound of the instrument, which by definition is completely free of distortion. Distortion would be any CHANGE in the frequencies from this natural sound, introduced during recording or playback.

That complex timbre of the natural instrument can mask THD added by recording & playback. Some instruments have a more pure tone with weaker naturally occurring harmonics (like flute in its top octave, and some female vocalists, especially with ancient music which has perfect intervals and no vibrato). These sounds can make it easier to hear distortion added by recording & playback. The opposite extreme can also work: complex natural sounds (like large acoustic ensembles) can trigger higher distortion levels from recording & playback, making that distortion easier to hear. Similar to a multi-tone test signal.

In short, distortion sensitivity depends quite a bit on the type of music. It would be much harder to hear in Led Zeppelin than in Eva Zaicik. And listener training also makes a big difference -- learning what distortion sounds like, how to identify it during critical listening.
 

amirm

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A lot of these distortion graphs are unreliable since they mix the distortion from the microphone with that of the headphone. Measurements mikes are rated to produce 1 to 3% distortion over their full SPL. I also find that the resonances caused by the cavities in the measurement gear increases the levels and with it, the amount of distortion created by the microphone.
 
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It's disingenuous to describe the sound of a bass guitar as 23% THD. If you mean the sum of all harmonics has 23% of the amplitude of the fundamental (12.8 dB lower), then it's incorrect to call it distortion. Those harmonics aren't distortion, they're the timbre of the instrument. Some acoustic instruments (like flute in its bottom octave) can have the 1st harmonic stronger than the fundamental. Shall we call it more than 100% distortion? Of course not. It is the natural live sound of the instrument, which by definition is completely free of distortion. Distortion would be any CHANGE in the frequencies from this natural sound, introduced during recording or playback.

That complex timbre of the natural instrument can mask THD added by recording & playback. Some instruments have a more pure tone with weaker naturally occurring harmonics (like flute in its top octave, and some female vocalists, especially with ancient music which has perfect intervals and no vibrato). These sounds can make it easier to hear distortion added by recording & playback. The opposite extreme can also work: complex natural sounds (like large acoustic ensembles) can trigger higher distortion levels from recording & playback, making that distortion easier to hear. Similar to a multi-tone test signal.

In short, distortion sensitivity depends quite a bit on the type of music. It would be much harder to hear in Led Zeppelin than in Eva Zaicik. And listener training also makes a big difference -- learning what distortion sounds like, how to identify it during critical listening.
This video demonstrates pretty clearly that not all distortion sounds alike.
 

MRC01

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A lot of these distortion graphs are unreliable since they mix the distortion from the microphone with that of the headphone. Measurements mikes are rated to produce 1 to 3% distortion over their full SPL. ...
That's true. When I run Room EQ Wizard frequency sweeps, I can see the difference in distortion measurements using different mics. The Rode NT1A shows lower distortion than the UMIK-1, but less flat FR.
 

Blumlein 88

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That's true. When I run Room EQ Wizard frequency sweeps, I can see the difference in distortion measurements using different mics. The Rode NT1A shows lower distortion than the UMIK-1, but less flat FR.
I can show you have to put together a cal file that REW would use for the NT1A. You'll not be able to fix the lower 200 hz altogether, but the rest of it can be evened out.

Here is a calibrated Umik (red) vs a calibrated cardioid Shure KSM32(green). Not a perfect match, but much closer.

1563920853097.png
 
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MRC01

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I can show you have to put together a cal file that REW would use for the NT1A. ...
I hacked a custom calibration file for the NT1A by starting with Rode's product info graph, then tweaking to match the response to the UMIK-1 which has a factory calibration. Is that what you did too? It ain't perfect, but good within a couple of dB, which is all I really need.
 

Blumlein 88

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I hacked a custom calibration file for the NT1A by starting with Rode's product info graph, then tweaking to match the response to the UMIK-1 which has a factory calibration. Is that what you did too? It ain't perfect, but good within a couple of dB, which is all I really need.
Yes, but there is an easy way vs just eyeballing if that is what you are doing.

https://automeris.io/WebPlotDigitizer/

Here is a good tutorial.

Web plot digitizer lets you drop images of graphs into it and spit out among other things a .csv file which REW will use. Play around with it some, and you'll get the hang of it. Export the result as .csv when done with the browser based version. I've done this with many microphones, and surprisingly those published graphs appear to be accurate. You can let it automatically place dots on the graph lines, parse out the color and it will do it fairly automatically. The biggie is setting the axis precisely and in logarithmic form.

TIP: if you can only find a black and white version, some photo editing software to air brush the curving graph a different color is enough this software will select the sample points correctly.

Once you have used it a bit, won't take long to grab a FR graph and spit out a cal file for your microphone.
 
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Blumlein 88

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One other tip. Almost any microphone plot can be found at www.recordinghacks.com
Like this one for the NT1A
1563928887339.png
 

Blumlein 88

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Since it takes a little while to figure the software out. I just used the above image and did it for you. I'm attaching a .csv file for the Rode you can use with REW. @MRC01
 

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Snarfie

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I have a superlux ecm999. I suppose to let it measurd to get an custom correction file.
 
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Blumlein 88

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I have a superlux ecm999. I suppose to let it measurd to get an custom correction file.
Well this microphone doesn't need too much correction. I found two different plots. They didn't vary by much from each other so if this one isn't perfect it shouldn't be too far off. This one was said to be a free field measurement in one location. The other from a pistonic microphone calibrator. Usually the graphs you see are from pistonic calibrators.
Superlux ECM 999.png
 

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Wombat

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The number of products out there is overwhelming. ASR can only test a small sample of them. Which ones to test? Try starting at the low-priced end and work up to and find products with adequate, or more, performance and let buyers decide beyond that. Avoid spending money to dissuade bigger spenders from spending too much - they probably aren't interested spending at more plebian levels , anyhow.

What I am saying is that don't waste money on testing expensive products when cheaper ones will do the job. The manufacturers should be doing that.
 
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Snarfie

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Well this microphone doesn't need too much correction. I found two different plots. They didn't vary by much from each other so if this one isn't perfect it shouldn't be too far off. This one was said to be a free field measurement in one location. The other from a pistonic microphone calibrator. Usually the graphs you see are from pistonic calibrators.
View attachment 29948
Thanx for sure i will give it a try. I will post the new measurments graphs with and without the calibration file.
 
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JohnYang1997

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There is nt1 2014 version. But no measurements of those microphone except from rode themselves. Form rode it's much flatter than nt1a.
 
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