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Active Room Treatment (ART) by Dirac

I expect that ART calibration will be simpler with other AVRs/Processors. Interestingly, the author applied a sort of BBC dip at 1 kHz to the target curve.
Really curious how that looks like.

In the meantime I'm making my 7.4.6 system (hopefully) simpler to implement ART with 4x 15" woofers built into the riser (mechanically decoupled from the seat though to avoid resonances) so the surround and surround back speakers gain power handling and full range extension.
 
You know, civilized discussion requires engagement, not merely lodging a dumb insult and then sidestepping the points actually made.

What points? You come in talking smack about Neural X that isn't true, downplay the usefulness of more channels, particularly in DTS:X, which with DTS:X Pro uses all available speakers as if they were rendered and then imply there are only ten people worldwide with >11 channel Atmos. I didn't say you had to know them in person.

Perhaps. I have no knowledge about that, as movie sound IMO isn’t that important.

It's the primary function of Atmos. You bought an Atmos system mostly for music? I Iisten to a lot of Atmos music, but most people I know online mostly use it for movies. I use Logic 7 for stereo music upmixing. It's by far the best stereo music upmixer I've heard. I plug an MC-1 into the 7.1 inputs and have a DC-1 in my Carver system and a third one in my exercise room (5.1).

In any event, it’s out of the scope of what I wrote: “stereo upmixer.” Generally, movies have not been in stereo for some time.

Most movies on disc still include a Dolby Surround stereo track, particularly older movies that get a new Atmos track so you hear the original (only 70-80 years worth of movies there so no big deal). But a separate stereo mix usually sounds better than a down mix so many new movies still include a stereo one on disc.

If what I’ve heard translates to movies, that means it tries to put sound all over the place, so you always know you have all those speakers. I guess some people prefer that over the system disappearing?

Neural X can make a 5.1 or 7.1 soundtrack sound like it's in Atmos or X. It's less precise with stereo, but still maintains front to back mixing overhead unlike DSU with uses a stereo array. I heard a golf ball hit the front ceiling in a TV show with Neural X.

The question of speakers "disappearing" isn't really about '70s or '80s mono surround arrays, but whether they image anywhere the sounds are placed or just at the speakers. I'm running 19 more or less discrete speakers (plus four experimental floor effects speakers and optional Surround Height for Auro-3D for 25 total plus subs) and the sounds image where they are placed in the room in Atmos, not at a speaker unless that's where it's placed.

I use dialog lift so not even dialog comes from a center speaker, but from about 30% upwards in the middle of the screen (adjustable). The left/right mains are set to image match at 30% also for a consistent front sound stage across the screen.

Maybe. We’re also talking about small rooms, and of course practicality issues.

I don't think Top Middle or Front Wides are all that impractical in many rooms. I realize some homes like in the UK tend to be smaller on average and maybe rear surrounds are harder to fit but Top Middle is just between the Heights or Tops (I'm using Heighrs+Tops instead because there's a steel beam box in the center of the room and I want consistent overhead panning).

My room is 12.5 feet by 24.5 feet by 7.5 feet so not huge, but maybe longer than average since I squeeze three rows in plus ss#2 in addition to front wides at ear level and eight (Heights+Tops) across ceiling with optional Surround Height above the sides on the side walls. I have four floor speakers beside the L/R mains and side surrounds (extracted from out of phase signals between the mains and surrounds) so ambient reflections come from the floor like live ambient reflections.

Besides, if you’re just talking about movies, the “imaging” is pretty much what you see on the screen. As long as the sound is close, it’s generally fine. Even Atmos bouncers work pretty well in concert with visual cues.

That's where I disagree 100%. When the flying car in the 2nd Harry Potter movie is going around as Harry is waking up 10 minutes in, the car flies high around the room on the left side and then the camera angle changes and it swoops in from behind my left shoulder moves directly overhead above me and flies right into screen. It does match the screen, but it doesn't start on the screen.

Similarly, a few minutes later at Ron's house, the owl swoops in from the back of the room over my right shoulder and smacks right into the screen. You almost want to duck because it's like a hologram moving across the room.

Yello's album Point in Atmos does a similar effect with a buzzy synth sound going from the center speaker (part way up the screen) flies straight towards me and passes just over my head straight into the back of the room on the song Big Boys Blues. If it doesn't sound like a real object buzzing past your head and almost freaks you out with your eyes closed because it sounds so real, then your system needs more resolution via closely matched excellent imaging speakers.


That is correct. I know personally exactly one household with an immersive system: ours. Admittedly suburbanites may know more such people. But immersive is a small niche in the world, unfortunately small in my view.

It's certainly more than ten people worldwide with >11.1 systems.


HTP-1 was never as a tenth as bad as Emo to start

I don't know about that. If your system won't reboot without a USB stick it's pretty bad. It's even worse that customers had to fix it. Newer Emotiva units are still buggy, but functional so I'm not seeing a huge difference between the early complaints. Either way, both had major issues and neither has delivered all the features promised.

never needed a separate computer box dongle for Dirac, and the early issues that did exist were remediated.

Most people use a laptop to configure DIRAC as far as I know. How's that not a dongle? The extra box is only connected during programming.

The big and potentially disqualifying HTP-1 glitch (the doom loop issue) was resolved largely by one very smart and generous user (+testers)

Yes, years later when it appeared Monoprice had abandoned the unit. They then reappeared, sent out some ART betas and were never heard from again. No actual working ART for regular users and still no DTS:X Pro SIX YEARS LATER!
 
You bought an Atmos system mostly for music? I

I’m going to ignore most of the off-topic blather. But two things…

No. I designed an immersive system solely for native and upmixed music as a foreground activity. Anything else is a peripheral concern. While thanks to Apple Music I’m listening to more Atmos content than ever, my core library is still 2 ch upmixed with Auro.

And you know what? ART will be used pretty much exclusively when it matters for music as well. At least I hope so, on my two HTP-1s or their successors. I have less hope for the Arcam AV41 driving a 2-channel system with 5 subs and DLBC, alas.

Yes, years later when it appeared Monoprice had abandoned the unit. They then reappeared, sent out some ART betas and were never heard from again. No actual working ART for regular users and still no DTS:X Pro SIX YEARS LATER!
That’s quite cold-hearted. Three minor things happened during this period: the pandemic, the DAC factory fire…and this device’s internal champion fought off cancer. Priorities, man.

Oh, also one of the key tech folks left MDS. Less tragic on a global scale but certainly a rough transition for a device built around MDS boards.
 
I’m going to ignore most of the off-topic blather. But two things…

No. I designed an immersive system solely for native and upmixed music as a foreground activity. Anything else is a peripheral concern. While thanks to Apple Music I’m listening to more Atmos content than ever, my core library is still 2 ch upmixed with Auro.

And you know what? ART will be used pretty much exclusively when it matters for music as well. At least I hope so, on my two HTP-1s or their successors. I have less hope for the Arcam AV41 driving a 2-channel system with 5 subs and DLBC, alas.


That’s quite cold-hearted. Three minor things happened during this period: the pandemic, the DAC factory fire…and this device’s internal champion fought off cancer. Priorities, man.

Oh, also one of the key tech folks left MDS. Less tragic on a global scale but certainly a rough transition for a device built around MDS boards.
Blather eh? I'm going to ignore you period. It's clear you don't even know what immersion means as you've obviously never experienced it.
 
Really curious how that looks like.

In the meantime I'm making my 7.4.6 system (hopefully) simpler to implement ART with 4x 15" woofers built into the riser (mechanically decoupled from the seat though to avoid resonances) so the surround and surround back speakers gain power handling and full range extension.
Piace the subs each one in the middle of the 4 Walls for best absolute performance
 
Piace the subs each one in the middle of the 4 Walls for best absolute performance
Is it really as easy as that in every room? What about DBA?
 
Here is what I said 1,111 posts and 111 weeks ago, when the thread was 1 week old:-
So, no measurements from nobody nowhere yet?
Does anybody recall any, without you or I having to sift through it? Measurements by ASR members.

thanks
 
Here is what I said 1,111 posts and 111 weeks ago, when the thread was 1 week old:-

Does anybody recall any, without you or I having to sift through it? Measurements by ASR members.

thanks
 
Thanks, but uh-oh. IMO that is much too big a change in frequency response.
 
Is it really as easy as that in every room? What about DBA?

Exactly! I indeed would love to implement a DBA if I had the room.

I'm constantly upgrading the AV set in my L-shape living room and the final plan is hiding all speakers so they fit seamlessly into our interior. I also hope that ART will do it's magic with 4 subs and 7 fullrange bed layer speakers.
 
Thanks, but uh-oh. IMO that is much too big a change in frequency response.
What?

I haven't been paying attention to the conversation, so I've really no idea what you're implying. ART fixes timing issues (reflections etc), which improves the frequency response. Did you read at least a page or 2 after the post I quoted? Because that's when I looked at the users mdat files and then gave my interpretation of the timing improvements, see https://www.audiosciencereview.com/...oom-treatment-art-by-dirac.40743/post-1724116
 
I am 'implying' that the listener might be responding mainly to the change in FR and increased SPL when ART is switched on, which could have been delivered with other means such as EQ. Uh-oh, that means we aren't listening only to the reduction in decay time.
 
Not sure if worth discussing ART beta, but my limited experience with it was that it reduced the SPL? Aka lower decay times and tighter bass so some SPL just went away compared to whatever we would call traditional methods. I am also still trying to understand if ART will use the full range speakers in the bed channel for anything else than cancelation?

I think Trinnov wave-forming is a good example of a different approach, but still the one that requires more hardware that most people would want to deploy?
 
the listener might be responding mainly to the ... increased SPL when ART is switched on
Nah. Most subs should be "flat" in the sense that their output should conform to the box tuning and filter slopes etc. The reason they don't measure that way in-room is because of the reflections making either peaks or nulls. ART is cancelling those reflections, which means it should be pulling down the peaks, and "raising" the nulls (not by SPL boost), and bringing everything in to alignment timing wise (hence a uniform waterfall, if that's what you're looking at).

You gotta understand that the frequency response you see in graphs like REW is based upon an "impulse", which is a "moment", not a sustained tone. Have you ever wondered what happens when you either measure or convolve a continuous tone? I did back in August 2023 (posted in other threads on here), but here's a screenshot of some screenshots;
Untitled.png
Look at the way all those tones "resolve" long term. Some go hard and then cancel themselves (eg 100Hz), whilst others are weak and slow to build up (eg 80Hz), and then there's 90Hz and 110Hz doing their impression of a roller-coaster. None of them raise quick and then hold steady, which is what you want.
(110 or 120Hz might have the best IR's of that bad bunch, and when you look at the decay graph you can also see that they have relatively good distance between red-to and blue-btm lines, which is indicative of the rate of decay).

But pay attention to the green markups I just added to 100Hz and 130Hz. Their sustained SPL is about equal at about "0.5", which is -6dB from memory (half power). But then look at the "reported SPL" on the decay graph, which in no way can you claim that 100Hz is in the ballpark of 130Hz, yet over a sustained tone they are. All of those tones start at 0.3ms, and are "stable" by 0.6ms. That's suggesting that 0.3ms of "sustained tone" is all it takes to "obliterate" the SPL curve you were expecting. I listen to heavy metal, and 200bpm is probably pretty average (a quick google suggests Slayer did that, and they have retired due to old age). Thats 200beats/60secs=0.3 beats/second. That tells me that just listening to a double-kick alone is enough to saturate my room, and then there's guitar(s) and bass and vocals and who knows what else over the top (slipknots got 9 bad members. they make noise!). What SPL am I getting then?

And if you need more convincing of "timing tricks", look at where cursor is. It's at ~64Hz, which is ~130/2 Hz. So 60Hz is not far from 64Hz, and comparing 60Hz sustained SPL to 130Hz, it's only a little stronger. But when you look at it's "reported SPL", it's meant to be at least 10dB lower.

And if you need more evidence, check out what happened when I sound deadened the whole wall - https://www.audiosciencereview.com/...ent-with-fluffy-insulation.49616/post-1782257 It's the same room as the above screenshot, yet it sounds so much better, thanks to the timing improvements.

PS - search my posts for "honk" or "honking", because that's how I described a regular problem in the past. Now I know that the "honking" is because of a sustained note on/near a peaking room mode, with the end result being a tone that is probably 20dB higher than it should be. I think it was a video from Earl Geddes that I watched (maybe the interview with Erin), and he said some stuff about loud sounds "shrouding" nearby tones. I think it's the other side of the same coin, in that peaking room modes can get real loud, and because of that we can't hear the nearby tones. So the music doesn't sound right, and you get tinnitus.
 
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