ARC (Anthem Room Correction) and PBK (Perfect Bass Kit) measurements and discussion

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sleepysurf

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I thought it might be interesting to view and discuss the results of ARC and/or PBK measurements for the newer ML speakers and subs that incorporate such capability.

It's interesting to see the variation in bass response depending on speaker/sub placement and room acoustics/geometry. The following graph is the ARC measurements for my Expressions from various seating positions...

ExpressionsARC.jpg

For years, I've struggled to overcome a 50-60 Hz bass null at the "sweet spot" with my (former) Summits, and now Expression 13A's. I'm still experimenting with the downloadable BF210 filter options to best integrate with the Expressions, but am fairly happy right now running the Expressions full range, and the subs dialed in as a stereo pair with the corresponding BF210 filters, as illustrated with this XTZ Room Analyzer measurement...

ML_Expressions_XTZ_FullRange (+ARC, +StereoSubs).jpg

It would be interesting to see other ARC/PBK graphs (also XTZ, REW, or OmniMic measurements) illustrating room effects and challenges!
 
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I am quite impressed with the Anthem arc 2 room correction. I found Arc 2 the only room correction i tried that didnt eq my system too bright. After running the simple pc Arc 2 program, bass bloat was gone and ringing (room modes ) were improved enough where bass traps were not really necessary anymore. I am using a Anthem avm-60 processor / preamp with dual subwoofers. I wish more room correction of this caliber was available for audiophile 2 channel systems, Anthem Arc 2 room correction really made a difference on my 2nd system.
 
Hi Alan, thanks for sharing this info. One question though: I sounds like you are running the Expressions full range + the Sub's? Isn't that resulting in doubled-up low-frequency?
Or is there an extra crossover I'm not seeing in your system layout?

What was the sequence of setup? ARC on the Expressions, followed by PBK for the subs? Singly or as a pair?
 
Hi Alan, thanks for sharing this info. One question though: I sounds like you are running the Expressions full range + the Sub's? Isn't that resulting in doubled-up low-frequency?
Or is there an extra crossover I'm not seeing in your system layout?

What was the sequence of setup? ARC on the Expressions, followed by PBK for the subs? Singly or as a pair?

I'm using the appropriate downloaded BF210 "EQ filter" for pairing with the Expression 13A's (running full range), and then manually "dialing in" the sub volume and phase for optimal integration. Most of this is still room dependant, but I've got minimal "bass overlap" at this point (lowest bass "house curve" manually tipped up slightly). Still have some final tweaking, but I'm probably 98% of where I want to be. Just listened to Jennifer Warnes/Rob Wasserman's Ballad of the Runaway Horse this morning, and it was sublime!

You're correct re the setup sequence... ARC for 13A's first (without subs), then PBK for each BF210 separately (since now running as stereo pair).

It would have been nice if I could run ARC for the entire setup, including subs, and have it automatically EQ each speaker. Perhaps the latest (or future) Anthem amp/processor will do that, but I don't have one. In the past (when I had the Summits) I tried an external crossover (I think it was a Marchand), but I wasn't happy with the result.
 
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Interesting so you split the output of the pre-amp to feed the mains and the subs, right?

I think ML missed an opportunity here on the new models, as they are equipped with pretty much all they need to support your use case. Just add an XLR 'Sub-out' to the Expressions, and enable a preset for the BalancedForce models, that way the ARC/PBK can be run once on the Expressions and it would integrate the sub, even selecting idealized crossover settings, as well as delay. Just plug the laptop into the sub after the measurements to have it download the new settings.

The incremental cost is minimal, as all the DSP is already on-board, and this level of vertical integration would result in even better outcomes for setups that leverage it. Maybe a feature to add on the mid-model change. Or even in an update to the DSP/Amp board and offer it as a retrofit.
 
I have no experience with the noted products but have experimented with DRC with my Sanders speakers.

I grabbed hold of an inexpensive Behringer DEQ2496 to see if I could improve upon the EQ in my room. I wasn’t really expecting much to be gained since a) my speakers are purposely made highly directional and so, thankfully, have very little high frequency (above 500 Hz) dispersion pattern errors b) the Behringer DCX2496 that I use to adjust midrange, midbass and deep bass EQ can, therefore, give me very good frequency response on its own. So, I figured I didn’t need a full blown DRC setup. Not so. Once I dialed in both of the Behringer’s, its taken things up a notch when I didn’t think anymore was possible. I am enjoying sound quality unlike anything I have ever heard before in my room.

I have been very impressed with the results I have achieved and am beyond glad I finally incorporated it into my setup. It takes some time to get a grasp of things but, once in play, it is very addictive.
 
The other additional feature I wish ARC (and other DSP/EQ programs) could automate would be phase/time alignment between mains and sub(s). Unfortunately, phase varies with frequency, and I doubt if there's a "standard" for how to do this. ARC (and my XTZ Room Analyzer Pro II) omits this measurement, so you need to manually set (I try to optimize it for the approximate crossover point).

Can REW measure phase? If so, I'll play around with that as well.
 
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Can REW measure phase? If so, I'll play around with that as well.

Yes, REW measures phase, and is very useful when tuning the mains to sub crossovers (slope, type, delay). The Waterfall views it shows are also helpful in 'seeing' the room modes, as long decays become visible in that graph.
 
Owned the 13a's since late July and only NOW applied the ARC software and PBK. Another forum member (michael) helped me via phone. Think I did it correct. Always had a little bass null at the main listening position. Whereas moving the seats back a bit closer to the back wall bass was better. I have dual powered servo subs that truly made a big difference BUT from talking to members and others I should be experiencing better bass from the ESL's by themselves. So thus the PBK and ARC.

Honestly it sounded the same LOL. So maybe something went wrong. Although it took all the measurements etc...and uploaded the responses. At first it was a tad less BASS. Weird. So I played around a bit with the Gain. Settled on +4. I think my room sux. :)

Anyone else use the ARC and didn't hear any improvements?
 
Hello,

I have a Descent i and Anthem pre/pro with ARC-1. Here is my ARC measurement for the sub channel. Note this is an average of 5 measured positions (the MLP is a lot worse). I have a peak at 65, 35 and the response tanks at 30 Hz. I would like to even it out and go lower, not louder (I have to keep gain below 4)! Do you think switching to dual BF 210 would help?

ARC_Descenti_front_left_center.jpg

Cheers,
Stefan
 
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You're correct re the setup sequence... ARC for 13A's first (without subs), then PBK for each BF210 separately (since now running as stereo pair).

It would have been nice if I could run ARC for the entire setup, including subs, and have it automatically EQ each speaker. Perhaps the latest (or future) Anthem amp/processor will do that, but I don't have one. In the past (when I had the Summits) I tried an external crossover (I think it was a Marchand), but I wasn't happy with the result.

So I have some 13a's coming to replace my Summit X's all the rest the same including 2 Descent i's and Anthem AVM60. I'm thinking that I should run the PBK on the 13's first then run the Anthem software for all my 7.2.2 setup including the 13's. It that right? In the past since I had the Summits X's nothing had the correction built into the speaker but now that the 13a's are coming I do.
 
Hello,

I have a Descent i and Anthem pre/pro with ARC-1. Here is my ARC measurement for the sub channel. Note this is an average of 5 measured positions (the MLP is a lot worse). I have a peak at 65, 35 and the response tanks at 30 Hz. I would like to even it out and go lower, not louder (I have to keep gain below 4)! Do you think switching to dual BF 210 would help?

View attachment 19526

Cheers,
Stefan

Switching to dual subs should enable smoother bass, as you can balance out some of the room modes with the right placement. Also, if you move your current Descent around, you might find a way of avoiding the null / peak at the MLP.
But multiple subs can give pretty good bass. I use 4 ML Dynamo 300's in a tiny (10' x 12' x 9') almost cube shaped (worst for bass) media room and the response is very smooth. In my HT I added a second sub centered on the back wall (existing one was centered on the front wall) and that substantially improved the balance, especially at the MLP.
 
So I have some 13a's coming to replace my Summit X's all the rest the same including 2 Descent i's and Anthem AVM60. I'm thinking that I should run the PBK on the 13's first then run the Anthem software for all my 7.2.2 setup including the 13's. It that right? In the past since I had the Summits X's nothing had the correction built into the speaker but now that the 13a's are coming I do.

Yes, run the PBK on the 13a's first, then run ARC on the Anthem.

I do the same thing (sort of), as I do a calibration (all manual using a REW measurement rig) inputting settings on the DriveRack 4800 Speaker Processor with minor EQ in the bass included. Then run Audyssey Pro for the Marantz AV8802A processor for the full 5.2.4 setup.
 
Switching to dual subs should enable smoother bass, as you can balance out some of the room modes with the right placement. Also, if you move your current Descent around, you might find a way of avoiding the null / peak at the MLP.

Thanks. I have a mode at 35 Hz no matter where I put the sub plus 65 Hz (in all speakers including sub).

I am considering moving the Descent to my 2-channel room because it looks nice and getting a pair of Dynamo 1500 for the HT to try and get more bass below 30 Hz. Dealer suggests I try Paradigm Ultracube 12 first.
 
Borrowed a second sub from the dealer and proved that it does smooth out my response if I set it 90 degrees out of phase. It also extends bass below 30Hz and above 80Hz!

Both subs are at the front of the room below the screen.

ARC_Descenti_front_left+Ultracube_front_right.jpg

Now must decide if I should get one BF 212 or dual 210's to have matching subs. Dealer does not recommend getting Dynamo 15" subs.
 
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Borrowed a second sub from the dealer and proved that it does smooth out my response if I set it 90 degrees out of phase. It also extends bass below 30Hz and above 80Hz!

Both subs are at the front of the room below the screen.


Now must decide if I should get one BF 212 or dual 210's to have matching subs. Dealer does not recommend getting Dynamo 15" subs.

I'd go for dual 210's, as you'll have more placement options and greater overall output than single 212.
 
I'm ordering two new ML subs (1500X) and wondering if I need to buy the PBK if I already have an ARC kit.

Can an Anthem ARC mic be used with ML's PBK software?

I know that an ARC mic can be used with Paradigm's PBK software (by renaming the .cal file) but I'm guessing the ML software is different. I can't test it out because I need to provide an ML serial number just to download the software!
 
I'm ordering two new ML subs (1500X) and wondering if I need to buy the PBK if I already have an ARC kit.

Can an Anthem ARC mic be used with ML's PBK software?

I know that an ARC mic can be used with Paradigm's PBK software (by renaming the .cal file) but I'm guessing the ML software is different. I can't test it out because I need to provide an ML serial number just to download the software!

I'm able to use my ARC Mic (from kit for ML Expressions) with the PBK software for my BalancedForce subs (downloaded using ARC Mic serial number, so includes proper Cal file). I presume it will work for you as well. What happens when you plug in the ARC Mic serial number on the ML PBK download page?
 
The ML page says it is expecting a number in the format 5xxxxx. My ARC mic number is 1xxxxx... Tried but it won't accept it.

I went ahead and ordered the kit since I was placing an order for the subs and saved on shipping getting everything together.
 
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