Active Room Treatment (ART) by Dirac

[audiomaestro]

If someone had a Neumann KH multi-channel system calibrated with Neumann's MA-1, in a decently treated room, would Dirac ART still have worthwhile benefits?

 

[Frank207be]

Why 50Hz ? The datasheet says 27Hz at -3dB. I understood the rule was +10Hz above -3dB if properly powered. Recommend amp is 50-500W.
Did you tried with f low at 40hz ?

Scala Utopia Evo - 3-way floor-standing speaker | Focal

Scala Utopia Evo, 3-way floor-standing speaker

www.focal.com

That's the latest EVO model. I have the 2008 first edition wich does 24Hz at -6dB. But with a 50Hz f-low I want to play safe with these expensive speakers. I blew the midranges during a way too loud sweep 2 years ago and I don't want this to happen again.

 

[Fidji]

If someone had a Neumann KH multi-channel system calibrated with Neumann's MA-1, in a decently treated room, would Dirac ART still have worthwhile benefits?

If you are happy with what you have, don't touch it.

ART will most likely improve the bass section, though with some minor trade-offs—ideally, you want plenty of headroom on your subs. Depending on which Neumanns you have, if your L-C-R are at least KH310s, it can work; the 150s are just too small. If your room is already on the drier side above 150Hz, ART will perform even better.

I have heard three ART installs now, and they all suffered from the same issue. While ART works wonders for controlling room resonances and tightening bass decay—often making it much shorter than the average midrange decay—the overall soundfield energy feels off, almost tilted toward the midrange.

On the other hand, Dirac tends to sound worse above the ART working range. If you are mainly using it for Netflix or gaming, it might not matter much, but if you are into music, I would weigh the pros and cons carefully. If you don't need much correction above 500Hz anyway, you could just run ART and skip the midrange and treble corrections entirely.

 

[audiomaestro]

If you are happy with what you have, don't touch it.

ART will most likely improve the bass section, though with some minor trade-offs—ideally, you want plenty of headroom on your subs. Depending on which Neumanns you have, if your L-C-R are at least KH310s, it can work; the 150s are just too small. If your room is already on the drier side above 150Hz, ART will perform even better.

I have heard three ART installs now, and they all suffered from the same issue. While ART works wonders for controlling room resonances and tightening bass decay—often making it much shorter than the average midrange decay—the overall soundfield energy feels off, almost tilted toward the midrange.

On the other hand, Dirac tends to sound worse above the ART working range. If you are mainly using it for Netflix or gaming, it might not matter much, but if you are into music, I would weigh the pros and cons carefully. If you don't need much correction above 500Hz anyway, you could just run ART and skip the midrange and treble corrections entirely.

I have 2 Neumann KH 120 II's for my L/R and will be getting KH 80's for my C and L/R surrounds. I don't own a subwoofer. I will simply send the lower frequencies into the L/R mains. I have a 20sqm room and am about to add room treatment on the rear-wall, ceiling, and a perimeter bass trap. I have the MA-1 already, but I'm about to buy a receiver. I was planning to either get a Marantz Cinema 70s or a Denon X3800H. Was deciding if it is worthwhile to get the Denon for ART compatibility if I already have MA-1.

Music and low-latency gaming are priorites. I know the MA-1 only introduces 1ms of latency, while DIrac introduces a lot, so I wouln't use Dirac fo gaming, only for music and movies, if ever it was worthwhile.

 

[KenMasters]

Music and low-latency gaming are priorites. I know the MA-1 only introduces 1ms of latency, while DIrac introduces a lot, so I wouln't use Dirac fo gaming, only for music and movies, if ever it was worthwhile.

ART does introduce delay, but without subs it probably wouldn’t be all that much. Subtract the 6-12ms delay of your display and you might find yourself hard pressed to notice anything off.

 

[Fidji]

I have 2 Neumann KH 120 II's for my L/R and will be getting KH 80's for my C and L/R surrounds. I don't own a subwoofer. I will simply send the lower frequencies into the L/R mains. I have a 20sqm room and am about to add room treatment on the rear-wall, ceiling, and a perimeter bass trap. I have the MA-1 already, but I'm about to buy a receiver. I was planning to either get a Marantz Cinema 70s or a Denon X3800H. Was deciding if it is worthwhile to get the Denon for ART compatibility if I already have MA-1.

Music and low-latency gaming are priorites. I know the MA-1 only introduces 1ms of latency, while DIrac introduces a lot, so I wouln't use Dirac fo gaming, only for music and movies, if ever it was worthwhile.

Sir, get yourself some subs first. No need to get ART now, as there will be no bass to correct. And I would re-think KH80 for Center.

P.S> or you can consider some good quality soundbar.

 

[Oddball]

That's the latest EVO model. I have the 2008 first edition wich does 24Hz at -6dB. But with a 50Hz f-low I want to play safe with these expensive speakers. I blew the midranges during a way too loud sweep 2 years ago and I don't want this to happen again.

That is a wise decision. I tried my LCR to 30-150 hz as that is their in room F3 and have been running them as such in previous Audy setup without any problems at very high SPL. Made no difference in ART as ART was picking up subs to support in that range. So rolled back to safer 50-150hz. Have 4 subs so I guess ART had sufficient support and based on that experience it prefers subs in that range if they can perform well.

 

[Oddball]

I have heard three ART installs now, and they all suffered from the same issue. While ART works wonders for controlling room resonances and tightening bass decay—often making it much shorter than the average midrange decay—the overall soundfield energy feels off, almost tilted toward the midrange.

On the other hand, Dirac tends to sound worse above the ART working range. If you are mainly using it for Netflix or gaming, it might not matter much, but if you are into music, I would weigh the pros and cons carefully. If you don't need much correction above 500Hz anyway, you could just run ART and skip the midrange and treble corrections entirely.

Not sure I understand the first point - what midrange are your referring to? IMO soundfield energy was never better. And my problem remains longer decay in sub 40hz frequencies as that is harder to control.

Dirac admittedly should do some futher work on Dirac Live overall and especially in the area where ART hands it over to Dirac Live.

There is also a theory that ART will fire your subs a bit earlier in certain circumstances to make sure they don't make a mess in the rest of the range with increased decay. Some measurements support that. Audible? Well it depends. Even if the difference is 40ms, perhaps it would be worse if not 40ms off. 40ms would be pretty bad if talking about lip synch, but this is a bit different. All my ART graphs are really good as I have reasonable tolerance, and at the end I do tend to choose by ear, including the subs firing earlier or latter.

 

[Frank207be]

That is a wise decision. I tried my LCR to 30-150 hz as that is their in room F3 and have been running them as such in previous Audy setup without any problems at very high SPL. Made no difference in ART as ART was picking up subs to support in that range. So rolled back to safer 50-150hz. Have 4 subs so I guess ART had sufficient support and based on that experience it prefers subs in that range if they can perform well.

Today after the annual cable cleanup behind the TV wall it was time to perform new ART calibrations with the higher 200Hz LPF on my Crowns, one set of measurements for the front seats and one for the back row. Very time consuming with all settings in the not so intuitive Dirac Software but totally worth the effort.

As expected ART responded with a 150Hz F-support High for the subs. I also tried use 40Hz for the front speakers as suggested but only to support each other and the center speaker and it truned out OK. I was also able to upload ART filters to both preset 1 and 2. Preset 1 is used for the front seat for stereo listening and preset2 for the back seat and movies.

But OMG... The switch to 150Hz for all subs finally unleashed the full potential of my set. With the lower LPF and a high Harman boost I always felt that there was something missing. While the Focal Scala can pack a punch I guess that the 11" woofers were not up to the task of fixing all midbass issues in my room. Now that 100-150Hz "gap" is filled with undistorted bass from all corners of the room while keeping the 15Hz extension which is awesome! I watched the final scenes of Dune part 2 at reference level and had a grin from ear to ear

 

[Oddball]

Today after the annual cable cleanup behind the TV wall it was time to perform new ART calibrations with the higher 200Hz LPF on my Crowns, one set of measurements for the front seats and one for the back row. Very time consuming with all settings in the not so intuitive Dirac Software but totally worth the effort.

As expected ART responded with a 150Hz F-support High for the subs. I also tried use 40Hz for the front speakers as suggested but only to support each other and the center speaker and it truned out OK. I was also able to upload ART filters to both preset 1 and 2. Preset 1 is used for the front seat for stereo listening and preset2 for the back seat and movies.

But OMG... The switch to 150Hz for all subs finally unleashed the full potential of my set. With the lower LPF and a high Harman boost I always felt that there was something missing. While the Focal Scala can pack a punch I guess that the 11" woofers were not up to the task of fixing all midbass issues in my room. Now that 100-150Hz "gap" is filled with undistorted bass from all corners of the room while keeping the 15Hz extension which is awesome! I watched the final scenes of Dune part 2 at reference level and had a grin from ear to ear

This seems to suggest that ART indeed prefers the subs. Although not sure why it lets them linger so high as 100-150hz. I guess will have to try as I roll them of starting at 80 hz and being 15 or more dB down by 150hz. You have a really powerful system and at least in my experience subs over 100hz are not really needed if you can support with other speakers with smaller and more flexible drivers.

 

[audiomaestro]

Sir, get yourself some subs first. No need to get ART now, as there will be no bass to correct. And I would re-think KH80 for Center.

P.S> or you can consider some good quality soundbar.

Noted regarding ART.

My room is solid poured concrete, there's no drywall, and I'm getting a lot of bass energy from the KH 120 II's. I never felt I was lacking bass. Every time I think about it not having a sub, I consider adding a Neumann KH 750, but when I actually sit down and start listening to music I always change my mind. Maybe I'm not thinking about it from the right perspective, though.

Why would I re-think the KH 80 as a center? I'm not disputing I'm just genuinely curious. My listening seat is just 6ft away if that matters. I will also correct it with MA-1.

 

[Frank207be]

This seems to suggest that ART indeed prefers the subs. Although not sure why it lets them linger so high as 100-150hz. I guess will have to try as I roll them of starting at 80 hz and being 15 or more dB down by 150hz. You have a really powerful system and at least in my experience subs over 100hz are not really needed if you can support with other speakers with smaller and more flexible drivers.

IMO relying on 4 subs is the safest bet as support capability of the D&M units is limited. With my A1H and the 7.4.6 layout I've used 93 out of 94:

Group	Front	Center	Surround	Surround back	Top Front	Top Mid	Top rear	4x Subwoofer
1 / Front	40-150							20-150 Infra
2 / Center	40-150	40-150						20-150
3 / Surround			80-150	80-150				20-150
4 / Surround Back			80-150	80-150				20-150
5 / Top Front					80-150	80-150		20-150
6 / Top Mid					80-150	80-150		20-150
7 / Top Back				80-150		80-150	80-150	20-150
8/ 4x Subwoofer								20-150 infra

My surround speakers only have 6.5" and 8" woofers so they lack the energy to fill that 80Hz-150Hz gap with the front speakers at elevated volume. But I find it quite odd that the system also sounds more natural and authoritative with all boost curves even at moderate playback.

Bottom line is that I'm very pleased with the actual result and I won't be touching the Dirac software for a long time to come. Yesterday it was very buggy with countless network interruptions

 

[kawauso]

I have 2 Neumann KH 120 II's for my L/R and will be getting KH 80's for my C and L/R surrounds. I don't own a subwoofer. I will simply send the lower frequencies into the L/R mains. I have a 20sqm room and am about to add room treatment on the rear-wall, ceiling, and a perimeter bass trap. I have the MA-1 already, but I'm about to buy a receiver. I was planning to either get a Marantz Cinema 70s or a Denon X3800H. Was deciding if it is worthwhile to get the Denon for ART compatibility if I already have MA-1.

Music and low-latency gaming are priorites. I know the MA-1 only introduces 1ms of latency, while DIrac introduces a lot, so I wouln't use Dirac fo gaming, only for music and movies, if ever it was worthwhile.

Please try to get ART if you can. Adding more subwoofers can be done whenever you feel like it. As for gaming latency, it doesn’t bother me.

This seems to suggest that ART indeed prefers the subs. Although not sure why it lets them linger so high as 100-150hz. I guess will have to try as I roll them of starting at 80 hz and being 15 or more dB down by 150hz. You have a really powerful system and at least in my experience subs over 100hz are not really needed if you can support with other speakers with smaller and more flexible drivers.

In kawauso’s experience, using subwoofers to provide support at higher frequencies is more effective than relying solely on full-range speakers. Even JTR subwoofers seem to handle support duties solidly up to around 150 Hz.

 

[Mort]

I never felt I was lacking bass.

I didn't feel that either until I heard the right tracks with big subs.

 

[kawauso]

Why 50Hz ? The datasheet says 27Hz at -3dB. I understood the rule was +10Hz above -3dB if properly powered. Recommend amp is 50-500W.
Did you tried with f low at 40hz ?

Scala Utopia Evo - 3-way floor-standing speaker | Focal

Scala Utopia Evo, 3-way floor-standing speaker

www.focal.com

With my S9900, I can use them down to 30 Hz, but in ART I have set the support range to start from 50 Hz. I do not notice any difference in sound quality, and starting from 50 Hz improves headroom, so that is why I use this setting.

IMO relying on 4 subs is the safest bet as support capability of the D&M units is limited. With my A1H and the 7.4.6 layout I've used 93 out of 94:

Group	Front	Center	Surround	Surround back	Top Front	Top Mid	Top rear	4x Subwoofer
1 / Front	40-150							20-150 Infra
2 / Center	40-150	40-150						20-150
3 / Surround			80-150	80-150				20-150
4 / Surround Back			80-150	80-150				20-150
5 / Top Front					80-150	80-150		20-150
6 / Top Mid					80-150	80-150		20-150
7 / Top Back				80-150		80-150	80-150	20-150
8/ 4x Subwoofer								20-150 infra

My surround speakers only have 6.5" and 8" woofers so they lack the energy to fill that 80Hz-150Hz gap with the front speakers at elevated volume. But I find it quite odd that the system also sounds more natural and authoritative with all boost curves even at moderate playback.

Bottom line is that I'm very pleased with the actual result and I won't be touching the Dirac software for a long time to come. Yesterday it was very buggy with countless network interruptions

Frank207be, that’s great to hear that you have finalized your ART settings. So you set the Crown’s LPF to 200 Hz and redid the calibration, right? My passive subwoofers also have a 200 Hz, 48 dB/oct LPF applied via miniDSP.

 

[kawauso]

I have 2 Neumann KH 120 II's for my L/R and will be getting KH 80's for my C and L/R surrounds. I don't own a subwoofer. I will simply send the lower frequencies into the L/R mains. I have a 20sqm room and am about to add room treatment on the rear-wall, ceiling, and a perimeter bass trap. I have the MA-1 already, but I'm about to buy a receiver. I was planning to either get a Marantz Cinema 70s or a Denon X3800H. Was deciding if it is worthwhile to get the Denon for ART compatibility if I already have MA-1.

Music and low-latency gaming are priorites. I know the MA-1 only introduces 1ms of latency, while DIrac introduces a lot, so I wouln't use Dirac fo gaming, only for music and movies, if ever it was worthwhile.

Please watch this interview video. In a small setup using only two 4-inch speakers, they said it sounded like it had the punchy bass of 6-inch speakers.

When I was experimenting with ART on and off in a minimal configuration, I had a similar experience. With Dirac ART on, my S9900 in 2-channel sounded comparable in bass impact to a 2.1-channel setup (S9900 + HSU 15-inch) with ART off (using Dirac Room Correction).

 

[Frank207be]

With my S9900, I can use them down to 30 Hz, but in ART I have set the support range to start from 50 Hz. I do not notice any difference in sound quality, and starting from 50 Hz improves headroom, so that is why I use this setting.


Frank207be, that’s great to hear that you have finalized your ART settings. So you set the Crown’s LPF to 200 Hz and redid the calibration, right? My passive subwoofers also have a 200 Hz, 48 dB/oct LPF applied via miniDSP.

Thanks Kawauso Everything indeed depends on required headroom and 50Hz is always a safe choice when you want to play undistorted reference level.

200Hz certainly seems to be a good choice for ART subwoofers. The Crown amps have a 24dB/oct LPF Linkwitz-Riley filter and changing the LPF indeed required new measurements.

Just a quick note about my passive DIY subwoofers. They are sealed for the lowest possible group delay and are equipped with large PA woofers with low Qts, low Le, high BL and decent X-Max to get the most accurate low, mid and upper bass. The enclosures are sized to get the best possible compromise between power handling, excursion and extension and so far they haven't dissappoined.

 

[Fidji]

Not sure I understand the first point - what midrange are your referring to? IMO soundfield energy was never better. And my problem remains longer decay in sub 40hz frequencies as that is harder to control.

Dirac admittedly should do some futher work on Dirac Live overall and especially in the area where ART hands it over to Dirac Live.

There is also a theory that ART will fire your subs a bit earlier in certain circumstances to make sure they don't make a mess in the rest of the range with increased decay. Some measurements support that. Audible? Well it depends. Even if the difference is 40ms, perhaps it would be worse if not 40ms off. 40ms would be pretty bad if talking about lip synch, but this is a bit different. All my ART graphs are really good as I have reasonable tolerance, and at the end I do tend to choose by ear, including the subs firing earlier or latter.

This is from MDAT ART file, that somebody posted here [or on AVSforum - impressive stuff and room acoustics better than 90% of rooms out there..
But if you look closely there is visible mismatch between ART and above ART frequencies - EDT looks completely different, like fivefold. Energy of bass fundamentals is long gone, there are still harmonics flying around for next half second. It makes LFE feel shallow, even when there is objectively high SPL signal there.

This correlates to my listening experience - while all the systems were clearly capable and bass was clean, punchy and tight, with lot of addictive qualities, there was something off - sheer weight and size were just not there - I have my reference tracks and clips and e.g. with fast panning bass heavy scenes in Top Gun or F1 you did not get this hit of air pressure that should be there. It reminded me of those “audiophile” 2 way speakers with mid bass bloom, designed for first impression.

What you actually want id linear increase of decay times below 100Hz, it can be freely double at 20Hz, once you remove ringing and resonances. My target is to be at 0.5-0.6s at 20Hz [which is below first room mode so no standing waves, just pressure build up]. Is a thing called Bass Ratio and it is how best classical concert venues are build - it creates envelopment and size.

Just for comparison - this is my room, with waveforming [dotted] vs ART [bold]

 

[Oddball]

In kawauso’s experience, using subwoofers to provide support at higher frequencies is more effective than relying solely on full-range speakers. Even JTR subwoofers seem to handle support duties solidly up to around 150 Hz.

As I note - will give it a try. Still have that fear from Audy that subs over 100hz will be a bit muddy, but then this is ART.

With LFE rolling of at 120hz and hopefully even before in good mixes, I can't see a theoretical reason why I would need to stretch the subs to 150hz though. Have two towers with twin 8"s and 4 passive 8" radiators each and 6 sealed 10" drivers for surrounds. They can all go very loud at 100-150hz range and with low distortion. It also seems that most subs would start to distort a bit more after 100hz - perhaps not JTR, but mine definitely seem to do so.

Burst measurements are probably not doing the justice and if subs are playing low in 100-150hz range distortion would likely be low and acceptable, but on principle basis I would think that dual 8"s or 10" drivers would be better suited for that range. If you start with 10hz, 100hz is 3 octaves and change up. A different ball game. But not first time I would be wrong so feel free to dismiss my comments that are, well, a but subjective.

Obviously, with smaller speakers, you might still want subs to support in that range.

Arendal 1723 has lower distortion on burst measurements but also rising from 80hz up.

 

[kawauso]

As I note - will give it a try. Still have that fear from Audy that subs over 100hz will be a bit muddy, but then this is ART.

With LFE rolling of at 120hz and hopefully even before in good mixes, I can't see a theoretical reason why I would need to stretch the subs to 150hz though. Have two towers with twin 8"s and 4 passive 8" radiators each and 6 sealed 10" drivers for surrounds. They can all go very loud at 100-150hz range and with low distortion. It also seems that most subs would start to distort a bit more after 100hz - perhaps not JTR, but mine definitely seem to do so.

Burst measurements are probably not doing the justice and if subs are playing low in 100-150hz range distortion would likely be low and acceptable, but on principle basis I would think that dual 8"s or 10" drivers would be better suited for that range. If you start with 10hz, 100hz is 3 octaves and change up. A different ball game. But not first time I would be wrong so feel free to dismiss my comments that are, well, a but subjective.

Obviously, with smaller speakers, you might still want subs to support in that range.

View attachment 512168

Arendal 1723 has lower distortion on burst measurements but also rising from 80hz up.

Subwoofers are not particularly good at higher frequencies, but distortion is generally low enough that I don’t think it is a major concern. If you set the upper support limit to 150 Hz, ART will use them appropriately. (By default, I believe the subwoofer support range is set to 20–150 Hz.)

If ART determines that other support speakers are more suitable, the subs simply won’t be used much in that range.
Although LFE rolls off at 120 Hz, ART’s use of subwoofers is not limited to LFE.