Proper way to set up my signal chain?

[Beast76]

Hi all - looking for some expert advice from the group. I’m not a dumb guy, but there’s still a lot for me to learn about audio.

What is the proper way for me to set up my system - specifically my multiple subwoofers:
I have an Emotiva XMC-1 with Dirac Live Full and a MiniDSP 2x4HD that feeds 3 subs (2 Powersound s3600i and a SVS 20-39 PC+). I used REW and MSO to match the subs. For MSO I used a target curve with a 10db gain from 100Hz to 20Hz and didn’t allow for any boost to be applied in the optimization. For Dirac I also used a 10db gain between 100Hz to 20Hz - with the difference being I’ve set up the curve so that at 20Hz I’m at 0 and I’m -10db at around 100Hz.

I love bass and I love watching movies very loud. In the most intense bass heavy scenes, my PSAs will clip (The SVS has a high pass filter to protect the woofer from bottoming and I haven’t heard it clip - from what I understand of the s3600i the design should prevent the woofers from ”bottoming out” so what I’m hearing is clipping - almost sounds like a really loud and rapid knocking on wood) I’m not sure if it’s the amplifier clipping because I’m asking it to do too much or if I’ve got my signal chain set up wrong and am sending a clipped signal to the amp. I’m hoping it is the latter and I can fix it.

So 2 questions: What is the proper way to set up my signal chain? Is there any way for me to know if the clipping is the amp or the signal I’m sending to the amp? Or am I even asking the right question?

 

[RayDunzl]

"knocking" makes me think a driver is hitting a hard physical limit, but I get to be wrong.

 

[AdamG]

Hi all - looking for some expert advice from the group. I’m not a dumb guy, but there’s still a lot for me to learn about audio.

What is the proper way for me to set up my system - specifically my multiple subwoofers:
I have an Emotiva XMC-1 with Dirac Live Full and a MiniDSP 2x4HD that feeds 3 subs (2 Powersound s3600i and a SVS 20-39 PC+). I used REW and MSO to match the subs. For MSO I used a target curve with a 10db gain from 100Hz to 20Hz and didn’t allow for any boost to be applied in the optimization. For Dirac I also used a 10db gain between 100Hz to 20Hz - with the difference being I’ve set up the curve so that at 20Hz I’m at 0 and I’m -10db at around 100Hz.

I love bass and I love watching movies very loud. In the most intense bass heavy scenes, my PSAs will clip (The SVS has a high pass filter to protect the woofer from bottoming and I haven’t heard it clip - from what I understand of the s3600i the design should prevent the woofers from ”bottoming out” so what I’m hearing is clipping - almost sounds like a really loud and rapid knocking on wood) I’m not sure if it’s the amplifier clipping because I’m asking it to do too much or if I’ve got my signal chain set up wrong and am sending a clipped signal to the amp. I’m hoping it is the latter and I can fix it.

So 2 questions: What is the proper way to set up my signal chain? Is there any way for me to know if the clipping is the amp or the signal I’m sending to the amp? Or am I even asking the right question?

Welcome Aboard @Beast76.

 

[Bear123]

10 dB "hot" at 20 Hz = 10x power being sent to your sealed subs. This may be more than they can handle despite being dual opposed 18's. It depends on your room size and listening level. "Very loud".....if this means reference level, that means 115 dB, plus 10 for your house curve which means your subs are trying to hit 125 dB at 20Hz and below.......more than this possibly with redirected bass. A pair of d/o sealed 18's can't do that unless its a very small room.

I suspect that, despite having very capable subs, you either need to add another pair to approach the capability you are asking of them, or move to large, low tune ported subs.

You'd be much better served with something like a pair of TV3612, FV25HP, or Cap4000. Even a pair of TV1812 or FV18 paper cone will match up better with your requirements.

 

[Beast76]

Thanks for your replies and the welcome! So I’m hearing I’m probably asking too much of my subs/amp and more than likely it’s not my signal chain? . I did have a brief email discussion with TomV at PSA and he told me it was “mechanically impossible“ for the speakers to bottom. My room is 16x16x10 with French doors and a 2 sided gas fireplace that passes through to a larger room.

Generally speaking, what is the “proper” way to run sweeps, apply house curves, etc? I assume my REW measurements should always be done without any DSP/EQ applied. Is there an advantage/disadvantage to running MSO with a flat target compared to a house curve if I’m going to run the house curve in DIRAC? In other words which would be ideal?
A - MSO - flat, DIRAC - house curve
B - MSO - house curve, DIRAC - house curve
C - MSO - house curve, DIRAC - flat

 

[Beast76]

Bumping this up and adding a question that seems very simple (and probably is) but I’d like a confirmation from the folks who understand this much better than I.
The minidsp 2x4HD is set from the factory with a 2V input sensitivity that can be changed to 4V with a jumper. My Emotiva XMC-1 can output 4V. Based upon my limited understanding, sending a 4V signal to the minidsp 2V input would result in the minidsp clipping .... am I understanding this correctly? And, if so, might the issues I’m describing above be a result of the input signal of the minidsp being clipped?