Audyssey might have suggested that you leave it on 0 degree (that's usually the default), but there isn't much reason (I think there is, but it's complicated..) to start with 180 either. If you had it set to 0 degree when running Audyssey, then you do NOT change it to 180 after. Likewise if you had it at 180, after running Audyssey, leave it there, do NOT change it to 0. My preference, follow instructions to the letter first, so 0 degree for me, always.
Here's the logic:
- You made adjustments to your subs, call that setting A, then you run Audyssey, so Audyssey creates filters based on the way the sub performed with setting A (the adj setting on the sub panel).
- Now you change the sub setting, so now you have sub setting B.
How can you expect Audyssey's filter to work well, that was created under sub setting A condition and now you changed it to setting B? By chance it could be better, but that would be random, by chance right?
Yes you can make slight incremental adjustment such as changing it from 0 to 20 degrees, or from 180 to 160 degrees if you then run Audyssey to check the results, but it is better to use the App because then you can save the original filter set, and can always go back, again, as long as you save the curve each time you edit with the App. I must have about 6 to 10 curves saved on my tablet, more on my desktop PC.
Note: If you use the App to make changes to the target curve, Audyssey will modify the filters accordingly so thing don't get messed up. If you make physical changes to the sub such as ports open/close, phase and levels etc., Audyssey will lose control, and in extreme case, you may as well turn it off.
I understand HSU suggested you can try different port and EQ setting after Audyssey, that's fine for people who don't have the luxury to use Audyssey and/or Editor App, and REW. In that case the user has to take such trial and error approach. You have the App, REW, so you don't need to follow HSU's. You still could, as long as the changes made are easily reversible, such as plugging unplugging ports, and as long as you use REW to compare the results and pick the one you prefer, by your ears, and eyes. You can also do the same with phase and levels if your HSU adj are made digitally, so you can again, always go back, if you record the original settings. If such changes are done via knobs, then it is better to leave them alone or you will lose track with your changes.
Simple rule: Run Audyssey according to instructions, follow it to the letter, then fine tune with the Editor App+Ratbuddyssey, run REW to compare results, save the best target curve, then you can start playing with different things to see if you can make further improvements.
I have spent countless hours on getting my bass flat (say within +/- 1 to 2 dB) down to 20 Hz, and sound good to me, with and without Audyssey, with and without minidsp 4XHD/REW. So I am not qualified to tell you not to go full blown anal about it, heck you have 3, 4 subs right, I only have 5
, but I am trying help you not do it/learn it the hard way I did..if you in fact cannot leave things alone and like to play..
(Just sit back and enjoy now could be your best option too!!)
I think Pogre and William are doing the same, sharing their own experience, though we may have some slight disagreements on how to get it done.