Not sure if it helps but at -10 MV and DEQ off i boost bass 4db in the AVR which gets me to -5.5 in AVR. I've also done the 4db boost just using the sub gain and leaving AVR at -9.5. The only difference i can notice is that doing it using the sub gain instead of AVR gives it a more robust sound.Im guessing its because the sub amp is doing more of the work that way.Hi,
First, I think it's a good call to believe that Audyssey can reduce your overall headroom somewhat, depending on how much it is pulling-up dips, compared to pulling down peaks. Audyssey attempts to compensate for that by allowing its software to pull-down peaks by up to 20db, but it can only pull-up dips by a maximum of 9db. Most rooms have both peaks and dips in the frequency response, so the loss of headroom from pulling-up dips, and the gain in headroom from pulling-down peaks, tends to even out. In your case, though, they may not even out, if you don't have many frequencies peaking to start with.
Second, although the graphs that you see aren't totally accurate (for instance, they only depict what Audyssey was trying to do, not what it actually did) they do indicate some issues that might be ameliorated with better subwoofer placement. Fortunately, fixing dips in the 40Hz to 80Hz range doesn't consume as much headroom, as fixing even lower dips would, but you might get better results if you experiment a bit more with sub placement and test the results with Audyssey calibrations.
Third, your volume level is pretty high. Combined with the sub boost you are using, you are putting a good bit of demand on your subs. Remember to keep your trim levels well in the negative range (say about -5) and use your sub gains to add most of your subwoofer boost, post-Audyssey. That will help to prevent clipping, which is a form of distortion, but one that might be harder to hear. Section II of the Guide explains gain/trim relationships in detail.
I definitely think that a couple of PSA V1510's would be a significant upgrade for the content and preferences you describe. The current line of PSA ported subs roll-off a little faster below 20Hz than some other subs do, but they are designed to have a lot of >25Hz SPL. I think that you would enjoy the upgrade, but remember that subwoofer placement is what causes the dips you are seeing in the before graph, and you would still want to maximize your pre-Audyssey response, even with the new subwoofers.
This is just something to experiment with. If you get serious about it, you might want to invest in a calibrated UMIK-1 and download REW. It's free, but takes a little time and effort to learn. You might, for instance, want to change the phase on one of your subs, in an effort to reduce cancellation currently occurring in the 40Hz to 80Hz range. But, I'm not sure that you will be able to do that successfully by ear, or just with an SPL meter. You can try though, by listening/measuring the volume of some test tones in that range, while adjusting the phase control on just one of your subs.
I think that trying to reduce the potentially large area of depression in your frequency response, between 40hz and 80Hz, will be helpful regardless of which subs you have, although the PSA subs will absolutely have a lot more native volume in that range than your Outlaw subs have.