ARC2, levels and trim control

We have worked to make the level difference between the corrected and
uncorrected audio minimal. However, the level difference will vary depending
on the frequency content and level of the program material. To further
minimize this difference and match corrected and uncorrected audio levels
(thus being able to fully appreciate the difference between the “before” and
“after”), use this trim knob. It has a range from -6 to +6 dB, and it should
be set so that the perceived loudness is the same for both the corrected and uncorrected audio.
Once the comparison has finished, please bring back the TRIM knob to its default position (0 dB) to avoid unwanted clipping of the signal.
 

batsbrew
then, when i output or bouncedown, i turn arc off, put the 'ARC' bus output to NONE, and re-route the master back to the main outputs of the audio card.

Danny Danzi
Sharke, here's how I do my stuff. It doesn't totally address your problem, but it works for me.
 
I use a master bus in each project. That bus is set to my main soundcard outs 1/2 during an export.
 
I create 2-3 buses that have an instance of ARC with the speaker correction I need.
 
My master bus outs during mixing will be sent to the ARC correction of my choice so I can hear the right monitors in an instant.
 
This comes up as a template for me. Before I saved it as a template, I ran test tones through the ARC buses with each different correction going on. Instead of messing with the trim on ARC, I adjusted the bus ARC was on in Sonar. I'm not sure how accurate that meter in the plug is and to be honest, I really don't care as I never look at it or even open the plug. What I do watch is my Sonar bus meters and make sure there is no clipping or weird sounds going on. 
 
When I'm read to export, I just set my master bus out to my main soundcard 1/2 and never worry about ARC. I usually play an entire pass of a mix through my master bus without ARC just to see what my final output levels are. I'm usually a little under -3 dB so I'm in good shape.
 
The test tone noise I used was inside my PSP Xenon limiter. It has some handy metering and tools in it so I used them to see how things were looking.
 
So to answer your question....
 
"Does this mean that as long as I have the trim control set to unity, I shouldn't worry about the effect that ARC2 has on levels when I'm mixing? In other words, when I eventually turn ARC2 off for the export, the levels I've arrived at with ARC2 on will still be correct?"
 
In my experience, I have NEVER gotten the same levels with ARC on or off. They are always different even at unity.
 
I pay no attention to the ARC trim and adjust the bus ARC is on. That's what I set using the Xenon test tones. This way I don't ever open ARC. The same is true with ARC 1 for me...which is my preferred weapon of choice over ARC 2. Hope some of this helps.
 
-Danny