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New Dirac MIMO active room correction

Keened

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I'd love to see some stand alone products with this similar to what Audyssey had with their "pro kit". Same for Room Perfect for that matter. Processing power has always held back AVRs IMHO.
The issue is full fidelity multi-channel digital audio is painfully locked down by DRM. If they accept the limitations of HDCP (and HDMI in general) they can't make the (digital) audio available for outboard processing.
 

Everett T

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The issue is full fidelity multi-channel digital audio is painfully locked down by DRM. If they accept the limitations of HDCP (and HDMI in general) they can't make the (digital) audio available for outboard processing.
Passing the digital audio signal with full DRM wouldn't be an issue, it's currently done on a multitude of products, albeit not common with most consumer gear, ie AVRs.
 

Krobar

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The issue is full fidelity multi-channel digital audio is painfully locked down by DRM. If they accept the limitations of HDCP (and HDMI in general) they can't make the (digital) audio available for outboard processing.

Not true in most cases. Output of 24/48 multichannel PCM is allowed with HDCP, this is why unprotected digital Dante and AES outputs are allowed on Storm, JBL Synth and Datasat etc.
 

Dani123

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Since most speakers, even smaller bookshelves, can do 80Hz at reasonable SPL, and the room transition frequency is often at a frequency much higher than that, especially in smaller rooms, I expect that full-range speakers all around should be nice to have, but not must have for the operation of DIRAC MIMO. Small speakers can fix issues between their -3db freq and room frequency, up to a certain SPL.
+1 !.
Tons of problems are (SBIR etc...) are at 80hz-150hz and above.
also - what about room gain from rear/ on wall speakers that goes to garbage( good thing) in DL algoritem? it is possiable that DLART- can reuse that for "anti" sound.
it is not uncomoon to measure 10-20 dB of room room gain at one octave below the F3 anacoic response.
 
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kemmler3D

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I wonder if Amir would be willing to do some in-room measurements (multiple positions, even) when this is more widely available. If this algorithm works as well as they say, it should approach game-changer level, and it would be nice to get an unvarnished view of the performance.
 

Everett T

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I wonder if Amir would be willing to do some in-room measurements (multiple positions, even) when this is more widely available. If this algorithm works as well as they say, it should approach game-changer level, and it would be nice to get an unvarnished view of the performance.
I'd imagine we will get plenty of people doing this, especially the early adopters.
 

Impossible

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Have I got this right, this has 2 benefits ?
1: cancells unwanted sound/noise from the room
2: enables speakers to be run full range

For the 2nd one, isn't bass none directional, so isn't crossover to subs enabling this. Given timing, phase and amplitude is correct.
 

dlaloum

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Have I got this right, this has 2 benefits ?
1: cancells unwanted sound/noise from the room
2: enables speakers to be run full range

For the 2nd one, isn't bass none directional, so isn't crossover to subs enabling this. Given timing, phase and amplitude is correct.

I don't think so...

1) is cancelling unwanted sounds, as in resonances and reflections of the original sound within the room (hence it isn't noise cancellation in the sense of attempting to cancel noise from other sources, outside road sounds, AC sounds etc...) - this is particularly used as a means to eliminate bass nodes within the room, as these are generated by the bass being reflected back and forth between the walls and surfaces.
2) It is capable of using and integrating ALL available speakers within the limitations of their individual frequency response capabilities... hence a bookshelf/satellite speaker with a crossover at 150Hz would contribute nothing (as current ART is limited to below 150Hz)
A more typical larger bookshelf with response down to 60Hz, will contribute to the frequencies it can provide (ie: 60Hz to 150Hz)
A full range speaker will therefore be able to contribute further down the frequency spectrum, to both the base sound and the active room treatment.

Other things to note - for the room treatment to be effective, it is likely that the SPL's required for the treatment are substantially lower than the main signal (you need to attenuate the undersirable aspects, you probably don't need to try to completely eliminate them - so you aren't trying to put out equal SPL's in cancellation - if you attenuate the undesirable sounds by 10db, they will effectively more or less disappear from the picture)... hence a speaker limited to say 60Hz (typical large-ish bookshelf) - but with a gentle long tailed roll off, (typical of sealed designs) will be down 3db at 60Hz... but might well have usable performance at say -6db @30Hz and possibly even further down... whereas something with a typical ported bass response might achieve its 60Hz, but thereafter have a very very steep rolloff, with effectively nothing there at 30Hz... this kind of speaker would have minimal contribution below 60Hz where the other type of design might be almost as effective as a full range speaker.

Hence, if Dirac ART, can deliver on the promise it has in theory, it would potentially lead to a dramatic change in speaker choices... people would then opt for speakers which in the traditional +/-3db frequency range, are more limited, but have a gentler more extended roll off in the bass (a return to sealed rather than ported designs?) - and of course, full range speakers would be even better (and a full range speaker with -3db, in a sealed design, might well have usable performance down at 15Hz !!)

So there is the potential for dramatic shifts in speaker preferences based on how well the speakers match with the requirements of Active Room Treatment.
 

Axo1989

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I don't think so...

1) is cancelling unwanted sounds, as in resonances and reflections of the original sound within the room (hence it isn't noise cancellation in the sense of attempting to cancel noise from other sources, outside road sounds, AC sounds etc...) - this is particularly used as a means to eliminate bass nodes within the room, as these are generated by the bass being reflected back and forth between the walls and surfaces.
2) It is capable of using and integrating ALL available speakers within the limitations of their individual frequency response capabilities... hence a bookshelf/satellite speaker with a crossover at 150Hz would contribute nothing (as current ART is limited to below 150Hz)
A more typical larger bookshelf with response down to 60Hz, will contribute to the frequencies it can provide (ie: 60Hz to 150Hz)
A full range speaker will therefore be able to contribute further down the frequency spectrum, to both the base sound and the active room treatment.

Other things to note - for the room treatment to be effective, it is likely that the SPL's required for the treatment are substantially lower than the main signal (you need to attenuate the undersirable aspects, you probably don't need to try to completely eliminate them - so you aren't trying to put out equal SPL's in cancellation - if you attenuate the undesirable sounds by 10db, they will effectively more or less disappear from the picture)... hence a speaker limited to say 60Hz (typical large-ish bookshelf) - but with a gentle long tailed roll off, (typical of sealed designs) will be down 3db at 60Hz... but might well have usable performance at say -6db @30Hz and possibly even further down... whereas something with a typical ported bass response might achieve its 60Hz, but thereafter have a very very steep rolloff, with effectively nothing there at 30Hz... this kind of speaker would have minimal contribution below 60Hz where the other type of design might be almost as effective as a full range speaker.

Hence, if Dirac ART, can deliver on the promise it has in theory, it would potentially lead to a dramatic change in speaker choices... people would then opt for speakers which in the traditional +/-3db frequency range, are more limited, but have a gentler more extended roll off in the bass (a return to sealed rather than ported designs?) - and of course, full range speakers would be even better (and a full range speaker with -3db, in a sealed design, might well have usable performance down at 15Hz !!)

So there is the potential for dramatic shifts in speaker preferences based on how well the speakers match with the requirements of Active Room Treatment.

Interesting train of thought. Magico becomes the state of the ART.
 

dlaloum

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Interesting train of thought. Magico becomes the state of the ART.
The Magico's have always been nice...

But there are a number of sometimes neglected brands that make sealed speakers which might find themselves back in the limelight... NHT, KLH...
Also some elderly designs like the famous LS3/5a by various manufacturers...

Right now sealed speakers are the exception - and you need to search them out....
I'm hoping that this will change, as I am a long term fan of that type of bass.... by observation rather than intent... the speakers I have liked over the years...since circa 1984... have almost all been sealed designs (and electrostatics, but that is a whole other thing)
 
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Axo1989

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The Magico's have always been nice...

But there are a number of sometimes neglected brands that make sealed speakers which might find themselves back in the limelight... NHT, KLH...
Also some elderly designs like the famous LS3/5a by various manufacturers...

Right now sealed speakers are the exception - and you need to search them out....
I'm hoping that this will change, as I am a long term fan of that type of bass.... by observation rather than intent... the speakers I have liked over the years...since circa 1984... have almost all been sealed designs (and electrostatics, but that is a whole other thing)

Yes, the first sealed full-range that came to mind. I hope there are more than a few others.
 

dlaloum

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Yes, the first sealed full-range that came to mind. I hope there are more than a few others.
There would be some excellent options available cheap that were made in the 1980's... but they may need some TLC... (woofer surrounds... etc...)

The Boston Acoustics A60/70/100/150/200/400 come to mind specifically (from personal experience), also a whole bunch of AR models (they were the leading light behind acoustic suspension for years!)
 

HarmonicTHD

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You can always plug ported full range speaker. Kef even delivers the foam plugs with its speakers for example.
 

Dj7675

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Have I got this right, this has 2 benefits ?
1: cancells unwanted sound/noise from the room
2: enables speakers to be run full range

For the 2nd one, isn't bass none directional, so isn't crossover to subs enabling this. Given timing, phase and amplitude is correct.
There is quite a bit of good info out there on ART to get a good understanding of what and how it is working...

What I find interesting is unlike the usual sub integration methods, you do not set crossovers for speaker groups, pairs etc.
Also, you do not need full range speakers to make it work. One of the demos they did had traditional surround speakers. However I do think it makes sense the closer to full range they are the better the affect will be.
To me it is a fundamentally different way of solving low frequency issues. Should be really interesting how things develp over the next year and what brands implement it.
 

dlaloum

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You can always plug ported full range speaker. Kef even delivers the foam plugs with its speakers for example.
A "plugged" ported speaker, and a true sealed design (where air compression provides additional support for the woofer) are quite different things.

I don't believe a plugged ported speaker behaves the same way as a traditional sealed / acoustic suspension design - the woofer driver design (particularly its suspension) is quite different...
 

ppataki

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There is quite a bit of good info out there on ART to get a good understanding of what and how it is working...

What I find interesting is unlike the usual sub integration methods, you do not set crossovers for speaker groups, pairs etc.
Also, you do not need full range speakers to make it work. One of the demos they did had traditional surround speakers. However I do think it makes sense the closer to full range they are the better the affect will be.
To me it is a fundamentally different way of solving low frequency issues. Should be really interesting how things develp over the next year and what brands implement it.
Just FYI sharing this here too:


I will spend a bit more time with the concept in the coming weeks
I hope that the real Dirac ART will even be better and that it will be available on a PC.... fingers crossed!

Right now sealed speakers are the exception - and you need to search them out....
I'm hoping that this will change, as I am a long term fan of that type of bass.... by observation rather than intent... the speakers I have liked over the years...since circa 1984... have almost all been sealed designs (and electrostatics, but that is a whole other thing)
I fully agree and I am all for sealed speakers too (much lower group delay, much better integration with the room, way better low end response if DSP-d properly due to the 12dB/octave low-end slope, etc. etc.)
I have been designing/building sealed full-range speakers in the last 2-3 years, all of them are shared here on ASR :)
 

Blanch

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Fully agree, I just wanted to comment exactly the same

Actually what we see in that video is called Dirac Unison (see their presentation attached) and it has been there for quite some time in the Volvo XC90....
Dirac have been making promises to make this available for home audio for many years now.....
Do any other cars have this?
 
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