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New excellent mitchco article on speakers and dsp

bunkbail

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That Tekton Ulfberht measured excellently after DSP! That speaker and NAD M33 (Purifi + Dirac!) is my dream combo for my future HiFi setup.
 
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PierreV

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That Tekton Ulfberht measured excellently after DSP! That speaker and NAD M33 (Purifi + Dirac!) is my dream combo for my future HiFi setup.

I like the speakers as well. I am going to lay low for a while I think given that I have to many of them already (Giya/Focal/Kef/Tannoy etc...) but those huge boxes are quite something indeed (and, relatively speaking, quite affordable). One must feel psychologically primed to be hammered when sitting in front of those beasts. And they seem to measure very well when DSPed as a bonus.
 

Absolute

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Excellent article! Thank you for taking the time @mitchco!

I like the speakers as well. I am going to lay low for a while I think given that I have to many of them already (Giya/Focal/Kef/Tannoy etc...) but those huge boxes are quite something indeed (and, relatively speaking, quite affordable). One must feel psychologically primed to be hammered when sitting in front of those beasts. And they seem to measure very well when DSPed as a bonus.
Everything measures good in a single point after heavy correction, even Klipsch! Here's an example of the uber-shit Klipsch RP-160M with no EQ, only manual EQ with Minidsp and then Audiolense;

Audiolense vs mindsp vs no eq.jpg



The question is, does this tell us much? All it takes for it to look good is a reverse filter of the measured response in the exact mic position.
In my opinion there's more to it than that, but no question that Audiolense can significantly improve on sound quality.
 

hardisj

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That is a really well-written and helpful article. Even to myself. I found his example of step response extremely useful and probably will even reference it on my site with future reviews so people can understand the 'ideal' step response.

Great job @mitchco !
 

SECA_alan

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It's an outstanding article, beautifully explained. Thank you, @mitchco !

I have a lot to learn, and a step learning curve to climb...
 

HooStat

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It is a great article which I need to read a lot more closely. I wonder whether and how much DSP affects directivity response? I know people become concerned about using DSP at higher frequencies, perhaps for this reason. I find myself a bit confused on the extent to which DSP can introduce problems.
 

Thomas savage

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North_Sky

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I am a proud learner and reader and music lover of some of the best audio forums and music accompaniment, including AudiophileStyle. ...Mitchco and company.
And here of course because people matter ...

* I started a thread especially because of that article, so it's nice to see others who also appreciate mitchco's awesome audio contributions to audio addicts of the highest caliber...up above the clouds, high in the atmosphere beyond the blue skies.

Hey, if you can't sing say it in words.
 

mitchco

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Excellent article! Thank you for taking the time @mitchco!


Everything measures good in a single point after heavy correction, even Klipsch! Here's an example of the uber-shit Klipsch RP-160M with no EQ, only manual EQ with Minidsp and then Audiolense;

View attachment 73572


The question is, does this tell us much? All it takes for it to look good is a reverse filter of the measured response in the exact mic position.
In my opinion there's more to it than that, but no question that Audiolense can significantly improve on sound quality.

Hi @Absolute, thanks and agreed. There indeed is (much) more to it than that, as you already know. Audiolense and Acourate use proprietary analysis and correction psychoacoustic filtering that other DSP products simply don't have. For the analysis side, one can see an example where in the bass, the dips are not completely filled in (it is not a complete reverse filter design, on purpose) and for the midrange and treble, the analysis sits very high in the comb filter and follows the envelope. This is based off of the excellent research JJ developed. This is not to mention getting into user settable frequency dependent windowing and other analysis/correction design aspects that are only available in the aforementioned DSP software.

In my opinion, the true measure of the success of room eq is how well it measures off axis around the listening position. This is where we see DSP solutions with either a limited number of correction filter taps and/or no time domain correction down low fall apart. As I have shown elsewhere and in my book, SOTA DSP solutions will cover a much larger sweetspot than other DSP solutions with the limitations mentioned. In my case, I get virtually identical frequency and time domain response across a 6ft x 2ft area that represents my couch in a 9ft equilateral triangle. I can listen anywhere on the couch with virtually no tonal shift and the bass remains even and solid no matter where I sit.

Wrt to the chart, 5 dB per div scale might bring out more detail with a 15 Hz to 200 Hz horizontal scale plus a legend. Maybe some time domain measurements too. Just teasing :)

I hope you are enjoying the music!
 

mitchco

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I am a proud learner and reader and music lover of some of the best audio forums and music accompaniment, including AudiophileStyle. ...Mitchco and company.
And here of course because people matter ...

* I started a thread especially because of that article, so it's nice to see others who also appreciate mitchco's awesome audio contributions to audio addicts of the highest caliber...up above the clouds, high in the atmosphere beyond the blue skies.

Hey, if you can't sing say it in words.

Thanks North_Sky, I appreciate your support from early on. I hope you are well.
 

spacevector

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For the analysis side, one can see an example where in the bass, the dips are not completely filled in (it is not a complete reverse filter design, on purpose) and for the midrange and treble, the analysis sits very high in the comb filter and follows the envelope. This is based off of the excellent research JJ developed.
Wait, Windows Vista has room correction?!?

Excerpt from the link:
James (JJ) Johnston began the presentation with some basic acoustic and psychoacoustic issues regarding room correction. He described the acoustic characteristics of a room, then some of the problems. If you want to correct the room-speaker combination for good imaging and timbre, exactly what do you correct and how? Long-term or short-term frequency response, or some combination? What about interchannel matching?
....
Serge Smirnov then described how this room correction procedure is implemented in the Windows Vista operating system.
 
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