Double stack ML subs?

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khenegar

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before u ditch ur cj preamp try using the anthem first as a preamp for awhile i thought my surround processor was good also it was replacing myARC LS27. didnt take me long to realize that i was missing something not having myARC LS27. CJ is not a slouch it’s good stuff.
 

barjohn

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I am starting to wonder about the accuracy of the Anthem ARC Genesis system. I have attached my measurement of my ML 800X subwoofer. Mind you my room is different and the sub is different and my placement is different; however, compare the 210 to my 800X. Our rooms are showing the same 200Hz mode and I am showing better performance than the 210 which makes no sense.
 

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IEnjoyOLED

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I am starting to wonder about the accuracy of the Anthem ARC Genesis system. I have attached my measurement of my ML 800X subwoofer. Mind you my room is different and the sub is different and my placement is different; however, compare the 210 to my 800X. Our rooms are showing the same 200Hz mode and I am showing better performance than the 210 which makes no sense.
The rooms are different and the placements are different. Why would you question the accuracy of ARC? The performance difference might “make no sense,” but I’m sure there’s an explanation that doesn’t require ineffective ARC.

Btw, I have an 800X, and I think it’s magically musical.
 

barjohn

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Would you expect an $800 subwoofer to outperform a $2K+ subwoofer at the bottom end? I wouldn't. Would you expect the room gain center frequency to be identical in two completely different rooms? Would you expect the same deep base boost value and center frequency with two different subs and rooms? Same tilt and tilt start frequency? Only the subwoofer crossover frequencies and the high pass frequency were different with the 800x at 21Hz with a min correction at 18Hz compared to the 210 at 25Hz and 21Hz respectively. Wouldn't you expect those values to be reversed? I am not saying it is wrong, just very suspicious and too much coincidence.
 

IEnjoyOLED

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We can agree to disagree, but I think you underestimate the effects of a room and overestimate the impact of more expensive gear.
 

barjohn

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Have you compared the response curve from REW to the response curve of a sub corrected with ARC Genesis? I have and they don't match even at ⅓ smoothing. Can someone else on here do the comparison? First measure a given sub with no correction using ARC Genesis and with REW and then do the same measurements after applying the ARC Genesis correction. I think it would be interesting to see how they compare. Of course this will raise the question which one is correct and to be trusted? Keep the sub in the same location so the room effects should be the same. Only measure from 500Hz down.
 

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I know exactly where to put a subwoofer in my room to destroy its response.

But in regards to comparing with/without ARC in REW, that's easy. I'll run that tonight. It "should" be pretty close to what I posted earlier.
 

ttocs

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So, the ARC and REW I previously posted was a before and after a new ARC run, not Off and On. The before was with ARC from a couple months ago and with the room setup differently. This is a ARC Off/On comparison. No smoothing, no other correction like PEQ, no Dirac.
L13A-ARC-ON-OFF.jpg
 

barjohn

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I assume this is an REW run comparison. How does this graph compare to the ARC Genesis generated graph. While it appears that the ARC correction is doing some correction, it appears to me to be minimal and does nothing for the major suck outs at 58Hz, 95Hz, 118Hz, 170Hz and 210Hz. Is this a measure of your sub woofers or the left 13A main speaker woofer?
 

ttocs

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I assume this is an REW run comparison. How does this graph compare to the ARC Genesis generated graph. While it appears that the ARC correction is doing some correction, it appears to me to be minimal and does nothing for the major suck outs at 58Hz, 95Hz, 118Hz, 170Hz and 210Hz. Is this a measure of your sub woofers or the left 13A main speaker woofer?
See the post on Page 1 for the ARC generated report.
This is only the 13A woofers.
ARC is pretty optimistic about what it thinks it will accomplish, so the predicted is not accurate.
 

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I like the ease of use of ARC Genesis but it makes me wonder whether Dirac or some other room correction would do a better job of reducing or eliminating those nulls.
 

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I have always been told that, in order of effectiveness, given a reasonable quality sub:
1. Sub placement and perhaps adding subs
2. Room treatment (bass traps)
3. EQ
9. Upgrade the sub
Also from what I’ve been told, since nulls are created through destructive interference, EQing them away is almost impossible.

I don’t know anything other than what I’ve been told, but it makes sense to me. The mileage I’ve gotten from room treatments far exceeds any I’ve gotten from upgrades (once past a minimum acceptable level).
 

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^ Exactly! And in that order. Placement is king.

Because I "want" to place my subs where they are in front, I've had to tweak the placement by moving my front stage left/right and change the spread to get the best I can out of it. It's a mix and match game.

Treatment only goes so far, so properly placing rear subs (in my situation) helps immensely.

With regard to ARC vs other calibration, each ML product can be corrected as best as possible unto itself. In my case, each of six subs, and each 13A, are individually calibrated, then, Dirac sees only each channel, which in my case means multiple subs per channel, so they are calibrated by Dirac as a group. This will not be the case if it's only one subwoofer per channel, in which case you will need DLBC (Dirac Live Bass Control) to calibrate EACH sub, then ALL subs/speakers as groups.
 

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ARC (and others) don't do much boosting to correct nulls. They (appropriately) focus on taming the peaks. Nulls are best dealt with by changing sub(s) placement in room, listening position, and acoustic treatment (if feasible). In my case, the corner stacked subs are actually better than my prior separate placement of them behind my couch/listening position. I'll post more ARC and XTZ Room Measurements in a week or so.
 

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Here's what Dirac did with ARC enabled the Left 13A. Most of the nulls were improved upon if only a little bit, mostly by making them narrower.

Again, no subwoofers are in play, just the 13A. No smoothing. Teal=ARC Only, Red=ARC + Dirac.
210820-01-DiracOverArc-L.jpg
 

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I do wonder if with some of the more advanced systems you can make accommodations for the dipolar nature of the panel. Anybody have any thoughts or information on that?
The Trinnov can deal with it thanks to the specialized 3D Mic and of course, their advanced DRC. See this quote from a Maggie user: Trinnov Altitude

But note the caveats (which I strongly endorse) regarding minimum rear-reflection delays and / or attenuation.
In general, for multichannel immersive audio (Auro / Atmos) or for movies, a ML ESL setup should have minimal reflected energy from the rear of the panels. Maybe some diffusion for the rear surrounds, but all others need a good 18dB or better attenuation of reflected rear energy. Also >24dB reduction in side-wall reflections to maintain an accurate soundstage.

Multichannel setup is *very* different than 2ch, where the reflected energy is used to create a wide soundstage (at the cost of the head-in-a-vise artifact).

As for other DRC's, they can work well enough if rooms are well-treated, but agree that in a 'normal' reflective room, they can royally screw up the mids and highs from any dipole speaker. But then, even without DRC, the sound of a dipole in untreated rooms, or placed too close to the wall behind (causing massive comb-filtering) are so inaccurate to start with, a physical fix is the only option.
 

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Here's what Dirac did with ARC enabled the Left 13A. Most of the nulls were improved upon if only a little bit, mostly by making them narrower.
That looks about as good as it gets considering the nulls are all due to room modes.
This is why combining well-located subs with mains and paying close attention to levels/delays before DRC can be effective at mitigating the nulls from the mains in the low-end.

Adding Mid-Bass Modules allows filling in room modes / lack of 'dynamics' from dipole speakers in the range the MBMs cover. It's been one of the best additions in the last 8 years (after the big room treatment deployment). Requires the right tools and knowledge to deploy, but man, amazing results.
 

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I have always been told that, in order of effectiveness, given a reasonable quality sub:
1. Sub placement and perhaps adding subs
2. Room treatment (bass traps)
3. EQ
9. Upgrade the sub
Also from what I’ve been told, since nulls are created through destructive interference, EQing them away is almost impossible.
Yep, that's the order, and you'll be surprised at just how many bass traps might be required.

As Scott's example with his 13A's show, those nulls are uncorrectable (via DRC) room modes. Actually impressed Dirac narrowed the notches.

I'm always surprised by just how good the media room low-end is, even with minimal acoustic treatments (no bass traps) in a room that is practically a cube (worst shape ever for low-end modes), thanks to 4 well-placed subs. And no fancy miniDSP integration either (yet), just Audyssey SubHT providing independent delays / levels for front vs. rear subs.
And those are the low-end Dynamo 300, I can't imagine what 4 800x or 1000x (largest that would fit) could do. But we don't watch action movies at reference in there.
 

GW1800

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Totally agree with Shawn.
I’m a Anthem user in my media room with 13’s and Decent i’s but long time user of PBK with my 2-212’s with my CLX’s in the music room. I have tried numerous times to calibrate my 212’s with ARC as it came available. Have not been that impressed with it and have now reverted to just use the outdated PBK calibration.
I’m waiting on my AVM-90 but will probably calibrate the 13’s with PBK then do ARC. I do know this latest version of ARC is much improved particularly in the bass but to my ear not up to PBK. but still prefer the older PBK for subs and my 13’s.
I also totally agree the new mic is much more impressive then the old and I would guess more accurate which is a head scratcher why I like the PBK.
I’ve told my son many times just because something is older does not automatically make it worse when something new comes along. I think this is one of these instances.
 
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