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Introducing Directiva - An ASR open source platform speaker project

TimVG

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I don’t think a microphone can tell what is direct sound and what is reflections like the human brain does. So there is no point in maintaining direct sound imo. We’re hearing the sum that is arriving at the microphone anyway.

All I can say is it certainly does matter - at least in the testing for personal sake I have performed in the past.

Tests were also performed by a couple of forum members in the past, and both in the first test by @thewas, and the second by @ctrl the speaker with the flattest direct sound (Revel F52 & Grimm LS1) was generally preffered with regards to coming closest to the recording itself. Link to the 2nd test because it also involved a KEF Reference 3 which arguably has the smoothest in-room response out of any of those speakers.


This is also my own preference in terms of speaker design. An as neutral direct sound as possible, within a large listening window, with reflections to match (with emphasis on the horizontal reflections). So this means constant (or close to) directivity over a large bandwidth. Basically as you move off-axis, the sound should simply become more quiet, but remain the same in terms of timbre - that is just my personal opinion of course.
 
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Newman

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I don’t think a microphone can tell what is direct sound and what is reflections like the human brain does. So there is no point in maintaining direct sound imo. We’re hearing the sum that is arriving at the microphone anyway.
???
It is tested and proven that flat direct sound FR is the #1 determinant of speaker preference.
 

abdo123

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All I can say is it certainly does matter - at least in the testing for personal sake I have performed in the past.

Tests were also performed by a couple of forum members in the past, and both in the first test by @thewas, and the second by @ctrl the speaker with the flattest direct sound (Revel F52 & Grimm LS1) was generally preffered with regards to coming closest to the recording itself. Link to the 2nd test because it also involved a KEF Reference 3 which arguably has the smoothest in-room response out of any of those speakers.


This is also my own preference in terms of speaker design. An as neutral direct sound as possible, within a large listening window, with reflections to match (with emphasis on the horizontal reflections). So this means constant (or close to) directivity over a large bandwidth. Basically as you move off-axis, the sound should simply become more quiet, but remain the same in terms of timbre - that is just my personal opinion of course.

I'm not denying or arguing against any of this, but at the end of the day the microphone will record the sum that is arriving at it and that sum will be what we actually hear when the recording is being played back.

These tests that you mentioned did not have EQ at all, so obviously the speaker with the best default tuning will be most preferred.
 

TimVG

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I'm not denying or arguing against any of this, but at the end of the day the microphone will record the sum that is arriving at it and that sum will be what we actually hear when the recording is being played back.

These tests that you mentioned did not have EQ at all, so obviously the speaker with the best default tuning will be most preferred.

By that definition however in the 2nd test, the KEF Reference 3 should have won featuring the best in-room response. In the end the Grimm LS1 (which had a flatter direct sound) was the winner, despite still having a dip in the overall soundpower (as any non-concentric multiway loudspeaker).
 

abdo123

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By that definition however in the 2nd test, the KEF Reference 3 should have won featuring the best in-room response. In the end the Grimm LS1 (which had a flatter direct sound) was the winner, despite still having a dip in the overall soundpower (as any non-concentric multiway loudspeaker).

Okay i am quite intrigued now.

Do you think the fact that it's a binaural recording it preserves some of the pshycoacoustics you would hear in-room successfully? The Grimm LS1 extends lower in frequency response, which we know is even a bigger proponent of speaker preference than on-axis linearity. But that extra extension is mainly below 40 Hz where there is barely any content in mainstream music.

Looking at it more closely now, the Grimm LS1 has quite the treble lift on axis, making it's ER / PIR have quite the flat slope, so perhaps what the microphone picked up in that instance was indeed flatter than the other speakers which was preferred more when played back on headphones.
 

TimVG

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Do you think the fact that it's a binaural recording it preserves some of the pshycoacoustics you would hear in-room successfully?

I cannot say for sure, but there appears to be a correlation - the only thing I've concluded with certainty so far is there is no such thing as a universal 'target' curve - simulated or measured.

Looking at it more closely now, the Grimm LS1 has quite the treble lift on axis, making it's ER / PIR have quite the flat slope, so perhaps what the microphone picked up in that instance was indeed flatter than the other speakers which was preferred more when played back on headphones.

I'm not sure how the LS1 were positioned in that test, but there is a setting which intends for the speakers beams to cross in front of the listener to reduce the sidewall reflections.

1655988171790.png


I do remain by my initial point however: The test by Erin is a good effort, and a good test by itself, I would however have like to seen the 'target' be based on the anechoic data, the direct sound, instead of an in-room target curve.
 
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