Active Room Treatment (ART) by Dirac

[Honken]

I have been beta testing ART

Can you disclose how? I'd be very interestd in trying this as well, I've given Dirac a try before and I wasn't very happy with the results compared to my manual REW EQ. But I've got an open mind and this sounds intriguing!

 

[TimoJ]

Can you disclose how? I'd be very interestd in trying this as well, I've given Dirac a try before and I wasn't very happy with the results compared to my manual REW EQ. But I've got an open mind and this sounds intriguing!

Limited beta tester group. Software is running on PC.

 

[Honken]

Thanks! I'll try to get in on that as well - using a PC as a source works for me.

 

[Dj7675]

While long, it has a lot of very good info. Thanks for posting. It does not sound trivial for manufacturers to implement. It will be interesting to watch and see how many manufacturers devote the resources for implementation.

 

[ooheadsoo]

(Posted this already to AVS but just in case someone is not following that forum I'll repost here.)

I have been beta testing ART. Starting from the first calibration, I noticed that something amazing is happening with bass notes...

Just before beta testing started, I had moved my system to a larger room, so I had not much experience how well DLBC works there. Subwoofer locations are not (yet...) optimized, they are just besides (closer to center) the main speakers. The room has no extra acoustic treatments.

The difference between DLBC and ART is huge. DLBC always seems to reduce bass and has these "out of phase" bass notes and room modes (if source material has lots of bass energy at that frequency) while with ART I get very exact and quick bass notes with almost pinpoint accuracy (of upper bass notes). Room modes are gone and bass output is not reduced at their frequency. Testing only with 2 channel music. Before this I got similar bass accuracy only with headphones.

In this new room DLBC actually sounded so bad vs. ART that I had to verify it was working correctly with the test software, Dirac verified it was.

I haven't noticed any weird effects or "cone of ART" where sound is noticeable different from the rest of the room. I just get much improved bass (and of course all the regular Dirac benefits). Bass seems to sound almost the same inside the whole speaker area. I'm using just one position for listening, so other locations are no interest for me, but I still have checked this.

My first setup was just 2.2 setup with Klipsch RP-280F mains and SVS SB-2000 subs. Then I tested with 3.2 setup with Klipsch RP-440C center. My current setup is 6.2 with 4x Polk Audio Signature S50e for surrounds and surround backs. HDMI limits channels to eight, so that is the maximum I can use.

I have also tested ART with just 2 channels (in a different room) and even with that it still handles room modes better than regular Dirac.

Any thoughts on latency for real time applications?

 

[TimoJ]

Any thoughts on latency for real time applications?

Not sure if you mean this, but PC (Windows) software adds about 120mS latency. But it probably is not yet optimized and I'm not sure if I'm using the lowest latency audio settings in Windows. Also, I think DSP based AVP/AVR should have lower latency.

 

[Gadgety]

The version that we are currently beta testing allows the user to decide about the frequency cutoff with a limit of 500 Hz.
And yes, the final name is Active Room Treatment as it's what it is and it's more understandable that it corrects the RT60
And no, I don't know if measurements were saved at CES.

I read an article by Mr Brannmark in AudioXPress on Dirac's spatial room correction. In it he referred to the MIMO paradigm used by Dirac to accomplish the co-optimization and control by multiple loudspeakers. In the piece he stated "...bass content of separate input channels is not re-routed to a single bass channel. It remains intact and is fed to separate (corrected and bass-extended) speakers." So bass is still processed as stereo. As far as I understand in DLBC bass is crossed over to mono below 80 Hz. Could you clarify how bass frequencies below and above 80 Hz are treated by Dirac ART?

 

[Gadgety]

(Posted this already to AVS but just in case someone is not following that forum I'll repost here.)

I have been beta testing ART. Starting from the first calibration, I noticed that something amazing is happening with bass notes...

Just before beta testing started, I had moved my system to a larger room, so I had not much experience how well DLBC works there. Subwoofer locations are not (yet...) optimized, they are just besides (closer to center) the main speakers. The room has no extra acoustic treatments.

The difference between DLBC and ART is huge. DLBC always seems to reduce bass and has these "out of phase" bass notes and room modes (if source material has lots of bass energy at that frequency) while with ART I get very exact and quick bass notes with almost pinpoint accuracy (of upper bass notes). Room modes are gone and bass output is not reduced at their frequency. Testing only with 2 channel music. Before this I got similar bass accuracy only with headphones.

In this new room DLBC actually sounded so bad vs. ART that I had to verify it was working correctly with the test software, Dirac verified it was.

I haven't noticed any weird effects or "cone of ART" where sound is noticeable different from the rest of the room. I just get much improved bass (and of course all the regular Dirac benefits). Bass seems to sound almost the same inside the whole speaker area. I'm using just one position for listening, so other locations are no interest for me, but I still have checked this.

My first setup was just 2.2 setup with Klipsch RP-280F mains and SVS SB-2000 subs. Then I tested with 3.2 setup with Klipsch RP-440C center. My current setup is 6.2 with 4x Polk Audio Signature S50e for surrounds and surround backs. HDMI limits channels to eight, so that is the maximum I can use.

I have also tested ART with just 2 channels (in a different room) and even with that it still handles room modes better than regular Dirac.

Could you post measurements?

 

[ElectricKoolAid]

While long, it has a lot of very good info. Thanks for posting. It does not sound trivial for manufacturers to implement. It will be interesting to watch and see how many manufacturers devote the resources for implementation.

It will be interesting, my guess is that MAYBE JBL/Harman will - though there have been reports on AVS that they are not planning to support it for some reason. Also maybe Monoprice with the HTP-1 (if it ever becomes available again and receives any updates, which so far has not happened for years). I'd love to see Emotiva implement it in their upcoming GP4 processors but have very, very low expectations that that will happen since DLBC isn't even available yet.

 

[TimoJ]

Could you post measurements?

Dirac wishes that measurements are posted only after next beta software update, it should arrive this month. AVS forums' Dirac thread will probably have measurements first.

 

[Gadgety]

Thank you for the reply, and the AVS heads up.

 

[abdo123]

Dirac wishes that measurements are posted only after next beta software update, it should arrive this month. AVS forums' Dirac thread will probably have measurements first.

Honestly it's kinda messy how this announcement is rolling. No measurements, No ready to use devices, no announcement of when ready to use devices will be available .etc

Like they canceled the CES announcement from last year so I excepted things to go smoother than this.

 

[oldtexasdog]

I have no empirical evidence but I implemented a DriveRack PA2 in my system to actively correct a room with bad acoustics. It has done very well I feel, better than Audessey in my opinion. I have not tried Dirac though.

 

[ooheadsoo]

Honestly it's kinda trashy how this announcement is rolling. No measurements, No ready to use devices, no announcement of when ready to use devices will be available .etc

Like they canceled the CES announcement from last year so I excepted things to go smoother than this.

I don't see anything "trashy". They had an exceptionally well received live demo, and are not making any promises they can't keep. Nothing wrong with that, and certainly better than cancelling another showing or staying silent.

 

[Gadgety]

Limited beta tester group. Software is running on PC.

Since you are using the ART part you can probably clarify the degree to which it processes bass as mono and stereo. In the videos from CES I sort of gathered that the main speakers output can be supported by other speakers but it still maintains the main speakers output. Bass is not sent to LFE mono exclusively. From previous information my understanding DLBC bass is crossed over to mono below 80 Hz. Having first hand experience could you clarify to what extent the bass frequencies are processed as mono or stereo by Dirac ART?

 

[TimoJ]

Since you are using the ART part you can probably clarify the degree to which it processes bass as mono and stereo. In the videos from CES I sort of gathered that the main speakers output can be supported by other speakers but it still maintains the main speakers output. Bass is not sent to LFE mono exclusively. From previous information my understanding DLBC bass is crossed over to mono below 80 Hz. Having first hand experience could you clarify to what extent the bass frequencies are processed as mono or stereo by Dirac ART?

I actually haven't checked/measured this, need to do some testing with REW signal generator. But I think this type technical details are still under NDA until Dirac talks about them. But with just listening stereo music (even in pretty close range of a main speaker) it sounds like only the main speakers output bass and not the subs (but the subs are still very active).

 

[Gadgety]

I actually haven't checked/measured this, need to do some testing with REW signal generator. But I think this type technical details are still under NDA until Dirac talks about them. But with just listening stereo music (even in pretty close range of a main speaker) it sounds like only the main speakers output bass and not the subs (but the subs are still very active).

Thank you for the reply. I don't know that it would be through the in room measurements necessarily but rather guess it could be seen in the settings? Earlier you stated "ART handles bass routing and filtering differently." DL Bass Control that you compared to ART is mono as far as I can tell from the following excerpt from a Dirac document "...bass controlled range which is common to all channels... higher frequencies are unique to...group." FLAK from Dirac earlier in this thread stated "...the correction applies at higher frequencies also... currently the beta tester can assign a 500 Hz limit." At this frequency sound it more sensitive to stereo signals, and certainly possible to localize. Perhaps the paradigm is different as in maintaining signal integrity, and stereo is mid+side in a mix, where mid is kind of mono anyway, so perhaps the distinction doesn't matter. The measurement window is longer, and the processing must be far more complex, that is for sure. That NDA seems a little vague.

 

[tknx]

Any clue where this is going to fit in the price spectrum? Like ubiquitous, only top end receivers ($2K+), specialized OTT processors ($5K), stratosphere like Trinnov ($10K+)

 

[hmt]

Well ATM only Storm offers it. So more like stratosphere.
Other brand did not commit themselves until now. That's the problem with dirac from the start: Not enough AVRs available with the recent tech and also nly the expensive ones. Now we have sort of affordable AVRs with basic Dirac but DLBC ist still limited to only some AVRs. I guess the problem is that it does not really fir in the business model of many manufacturers to offer more functionality for a fee that that was promised. They want to sell you new AVRs instead.

 

[tknx]

I am hoping it becomes a volume licensing play... I'd be willing to buy a premium AVR for this feature, but probably no more.