I tried Arc2 for about year some time back.  Never worked for me and my mixes were worse.  Not bashing, I am glad it works for others.  For me, I just had to take the time to learn my room and speakers and I am glad I did.  I was able to go into a friends studio at his house, listen to two or three reference tracks, learn his room and help him with a problem mix.   I am glad I learned "how" to learn a room.  Can't take room correction everywhere with ya.  Just my opinion.  In other news (not sure if it's transferable) but I have an Arc2 system for sale!  Cheap!

dmbaer

ULTRABRA
What does it mean when there is still a dip in the corrected curve - is that frequency still going to be a problem?  Why doesn't it flatten it out there too?

One important thing to be aware of is this.  The line shows level adjustments.  As I understand it, ARC also makes phase adjustments that, at low frequencies, can have a significant effect.  There is no visible feedback on this.  My displayed adjustments look contrary to the level adjustments that happen as I switch between enabled and disabled state.  I'm pretty sure this is because of the not-shown phase adjustments.

If you listen to ARC2's output out of context (e.g. through headphones) you can hear the phase adjustments it makes very clearly. It will make a mono track sound stereo, although not in a good way. The low end widens right out.  

Thanks for the replies.
 
I'm still a bit unsure though ... if I still have that dip at around 75hz, then ok, its an improvement on previous, but its still not near flat, so how can I still trust what I'm hearing?   Do I need to find another room?  
 
I did the room test twice, the 2nd time much more carefully, and the result was similar - in fact the more careful reading was worse, but the curves were similar shape.  

but it is possible to disable the automatic roll-off point detection by selecting Full Bass Range Correction mode.

 

Yes, I did select the Full Bass Range Correction - although its not a roll off that's the issue, its a dip at the specific frequency 75hz.

Not to be facetious , but how does commercial material sound through it with the settings that ARC has chosen?
Would test it by playing some familiar commercial material through your system that you know the sound of.
Also it wont hurt to just go ahead an mix some material on it, as it is and see where the material lands sonic wise on playback outside your room.

Just how much correction is the ARC system having to make?  I have a similar dip, but this is because around the frequency of where the dip is, the room is changing between massive bass attenuation (absorption) and a massive bass boost (room modes); it is simply not possible for filters (and whatever time-domain correction the plugin is also performing) to perfectly correct the frequency balance due to the massive swing in room response around the frequency in question; the filters will interfere with each other.  So, like many things, it is a compromise.
 
Here's my ARC2 curves:
 

 
Before I started using ARC2, I made my own frequency-domain only correction, using a stack of 3x parametric EQ's and a channel tool, as follows:
 

 
This wasn't perfect, especially around the lower frequencies, but my point is that any attempt on my part to correct the frequency response around that area any further lead to the various filters interacting with each other to totally ruin the sound, so I had to compromise and achieve the best response I could.
 
Honestly, the small dip around 75Hz in ARC2 is still a huge improvement compared to how the room sounded before and is easily corrected for mentally.

I've had ARC2 for several years which has helped me learn my own speakers better.  I find the most useful feature of ARC2 is the simulations of various speakers.  This has helped immensely, especially the car stereo, boombox, and laptop emulations.  I now have confidence that my mixes will sound good on those speakers in real life.  The ARC2 in conjunction with my VRM box have changed nearly every aspect of my productions, and much time has been saved by not having to "test drive" my mixes on other systems so much.

I haven't used ARC in years (bought it long time ago) as it does not seem to do any good if you are familiar with your speakers and your (hopefully acoustically treated) room. If not, ARC will not save you either.
 
Just for the fun of it I gave it another go this summer and I did not like what it turned my reference tracks into ... anyone wants it? don't know if it's transferable but I won't use.

ston
Just how much correction is the ARC system having to make?  I have a similar dip, but this is because around the frequency of where the dip is, the room is changing between massive bass attenuation (absorption) and a massive bass boost (room modes); it is simply not possible for filters (and whatever time-domain correction the plugin is also performing) to perfectly correct the frequency balance due to the massive swing in room response around the frequency in question; the filters will interfere with each other.  So, like many things, it is a compromise.
 
Here's my ARC2 curves:
 

 
Honestly, the small dip around 75Hz in ARC2 is still a huge improvement compared to how the room sounded before and is easily corrected for mentally.

Mine looks quite similar to yours, except the orange curve dip is well below the -12 line, and the white line on the left is dipping to the first white line on the graph (-3db?) and on the right side to the 2nd white graph line (-6db?).