Cool - that was something I was trying to figure out. I didn't want the crossover active with the 990 already handling bass management, but I found no way to disable the crossover (scrolling up past 199 seemed like a possible method, but it just rolled back around on me). I'll give the reset trick a try.

Make sure your not trying to boost a null... and even if not a null, 2-3Db boost could be ok but no more than that… I don’t remember the "formula" but for every xDb boost, your sub will have to work x amount of time harder to compensate and it can be very stressful for your sub... Good thing you knew about that stuff and didn't trust the auto setup (your poor sub would have taken a big hit)...

disabling the crossover for the sms is in the manual but again it is very obscure. i was tipped off about it by the guys at outlaw tech.

i actually didn't know about how damaging the boost could be until i was told about it. but i wasn't trying to boost areas of my sub output where my sub didn't have any

Sure enough, I found mention in the manual of both the "RESET" trick for disabling the crossover and of the ability to adjust each EQ channel to the desired frequency. It appears that the Velodyne DD sub manual has a few extra screen shots along with nearly the same text compared to the SMS-1 manual.

Does this mean that the auto EQ could possibily fill in nulls to a dangerous degree? I have some serious nullage in my room . I just got this today and I am going to set it up tomorrow.

If a particular dip in your FR doesn't respond to EQ attempts, it's most probably a room induce null. Nulls tend to be sharp and deep. Some people locate their sub where there are fewer nulls and then only cut the peaks... There is nothing wrong with boosting (IN MODERATION) when you are sure it's not a null. You can't overcome severe nulls with EQ, period. Just watch out for cone overdrive, loss of headroom, and amp clipping...

OK but the SMS won't try to fill that in automatically to get a flat response? I am just concerned because I am kind of new at this whole EQ thing that I won't catch it if it does. I was reading the manual last night and my head spun.

Someone else will have to jump in and reply since I don't own an SMS and I'm not familiar with the algorithm it might use in the automatic mode...

The SMS's automatic software most likely leaves the EQ's at their default frequencies (that would massively simplify the number of variables being addressed), so if a null hit at one of those EQ frequencies it would probably increase the EQ to the max. The danger that exists with manual EQ is that you can stack two EQ channels at the same point and push both to the limit to address such a null - at which point the sub's driver is being asked to operate at 12dB higher output at that point than the baseline, which could be considered similar to asking the sub to run 12dB "hot" (something that could be painful to a driver when you throw some deep bass at it).

My brain is still not graspng this. I am sure that it is simpler than I am making it. I am going to give Steve a call.