While the body of my objectives with incorporating two different style subs over their own respective frequencies has been answered, im still at a loss for how to optimize the delay across ALL the speakers. right now I have two XXX18's in the corners of my theater under the screen, and then two JBL 4648a's under the screen for midbass. the XXX18's will run from 40hz down and the JBL's from 40 or 50hz up to 120hz. My AVR has xt32 so there are TWO sub test tones and then a combined. my question here is, should I make audyssey see the left XXX18 and the left 4648a as a "single" speaker and the right pair as the other, or should I have audyssey see the jbls as a single speaker and the XXX18's on the outside as another speaker. It would seem to me that to get the best phase/delay out of the double sub test that the former would be optimal, since the RE's are the furthest away from each other, but I dont know if it is even a big deal or not. Here is my post over in the DIY section 
any pointers here would be appreciated.
any pointers here would be appreciated.Quote:
Hey dudes, while AVS was down I went to HTS to get some ideas on the next logical step in the progression of wiring and incorporating these two sub systems, while some of what is in this post is repeat from what has been said here, give er a browse and lemme know which option you think fits best for my situation. The 40hz cross is already decided on, the placement as well, all up front. slopes for the XO's (thx LTD), just need to figure the best way to make it all work in concert. The only suggestion ive gotten over there is to do option 1 (easiest) and REW then audyssey, then REW again to see what im starting out with. here is what I wrote:
Quote:
My objective is to incorporate the two subs by using the RE's for the 5-40hz material by putting a 4th order lowpass at 40hz and letting them run wide open below that, and using the 4648A's from 40hz (2nd order HPF combined with its natural rolloff at that tuning freq for a 4th order HP basically) up to 120hz where they will cross to my mains. all the subs will be run via the DCX for filtering purposes, but connecting the devices properly is where I am atm. Since I have xt32 on the denon, I believe I have some connection issues to iron out before I move on, being able to eq two different subs causes a kink. the RE's are stereo off the amp, but just being run with a mono signal TO the amp (still need two cords from the DCX, one for each channel). The 4648A's will be input 2 on the DCX and will have a single cable running from the DCX to the epx4000 run in stereo mode. Here are the options ive considered, tell me which you think is most appropriate:
1) run the RE's from one sub out on the 4311 to the DCX and the 4648A's from the other sub out. next step would be to set the delays of the two seperate sub systems. With them set this way I would assume xt32 would set it's own delays for each system properly since each 'type" of sub is on a different channel. SO in this case: eq the subs before audyssey, get severel filters in there to acheive flat response and run HP and LP filters etc, then let xt32 set the delays of each system (or is this bad since the RE's are the furthest apart and therefore the most different distance-wise from the MLP which is off center by a few feet?)
2)same as above, but dont set the XO points, just eq both systems full range (well up to 120hz), then audyssey (still both seperately eq'd with xt32 and full range), then go back to DCX and set xo's and tweak response around the XO point of 40hz. This may be the way to do it IF xt32 sees one sub's response drop off at 40hz and the other's pick up same spot and tries to do some crazy eqing below that point to compensate, even though i wouldnt WANT that sub to be doing anything down there. Im pretty sure that with the XO filters set in place, that audyssey sees the rolloff as "on-purpose" and doesnt eq if the rolloff is steep enough.
3) make it so the LEFT XXX and left 4648a is off one sub out from the 4311 and the right two are from the other, obviously have to do the 4648's in stereo mode from the epx at this point, but no big deal there. I would then set the left two subs delay and xo points and all from the DCX before anything else and then do the same for the right 4648 and XXX18. Doing it this way would make audyssey "see" the left combo of subs as ONE sub, and the right pair as the other. This IMO might be a better way to set the OVERALL delay of the system since I could do the initial delay settings between the two different types of subs using the DCX, then audyssey could adjust the OVERALL delay of the combo for the left AND right systems. Have I lost anyone yet?
With all that said, I dont know if the third option is even that critical, since the furthest sub (left xxx) is only about a 3 foot difference from the closest sub (would be the right 4648, but until the second 4648a arrives, the right XXX is actually the closest)
I dont think ive left anything out, and my initial plan was option 1 until i got to thinking about whether audyssey wouldnt like seeing one sub system sloping off at 40hz, and the other picking up there and going to the top of the range, where that immediately made me think it would do things I didnt want it to do.
Consider the top options and please weigh in!!
Quote:
My objective is to incorporate the two subs by using the RE's for the 5-40hz material by putting a 4th order lowpass at 40hz and letting them run wide open below that, and using the 4648A's from 40hz (2nd order HPF combined with its natural rolloff at that tuning freq for a 4th order HP basically) up to 120hz where they will cross to my mains. all the subs will be run via the DCX for filtering purposes, but connecting the devices properly is where I am atm. Since I have xt32 on the denon, I believe I have some connection issues to iron out before I move on, being able to eq two different subs causes a kink. the RE's are stereo off the amp, but just being run with a mono signal TO the amp (still need two cords from the DCX, one for each channel). The 4648A's will be input 2 on the DCX and will have a single cable running from the DCX to the epx4000 run in stereo mode. Here are the options ive considered, tell me which you think is most appropriate:
1) run the RE's from one sub out on the 4311 to the DCX and the 4648A's from the other sub out. next step would be to set the delays of the two seperate sub systems. With them set this way I would assume xt32 would set it's own delays for each system properly since each 'type" of sub is on a different channel. SO in this case: eq the subs before audyssey, get severel filters in there to acheive flat response and run HP and LP filters etc, then let xt32 set the delays of each system (or is this bad since the RE's are the furthest apart and therefore the most different distance-wise from the MLP which is off center by a few feet?)
2)same as above, but dont set the XO points, just eq both systems full range (well up to 120hz), then audyssey (still both seperately eq'd with xt32 and full range), then go back to DCX and set xo's and tweak response around the XO point of 40hz. This may be the way to do it IF xt32 sees one sub's response drop off at 40hz and the other's pick up same spot and tries to do some crazy eqing below that point to compensate, even though i wouldnt WANT that sub to be doing anything down there. Im pretty sure that with the XO filters set in place, that audyssey sees the rolloff as "on-purpose" and doesnt eq if the rolloff is steep enough.
3) make it so the LEFT XXX and left 4648a is off one sub out from the 4311 and the right two are from the other, obviously have to do the 4648's in stereo mode from the epx at this point, but no big deal there. I would then set the left two subs delay and xo points and all from the DCX before anything else and then do the same for the right 4648 and XXX18. Doing it this way would make audyssey "see" the left combo of subs as ONE sub, and the right pair as the other. This IMO might be a better way to set the OVERALL delay of the system since I could do the initial delay settings between the two different types of subs using the DCX, then audyssey could adjust the OVERALL delay of the combo for the left AND right systems. Have I lost anyone yet?
With all that said, I dont know if the third option is even that critical, since the furthest sub (left xxx) is only about a 3 foot difference from the closest sub (would be the right 4648, but until the second 4648a arrives, the right XXX is actually the closest)
I dont think ive left anything out, and my initial plan was option 1 until i got to thinking about whether audyssey wouldnt like seeing one sub system sloping off at 40hz, and the other picking up there and going to the top of the range, where that immediately made me think it would do things I didnt want it to do.
Consider the top options and please weigh in!!
