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I would employ a steeper house curve, perhaps 10DB, and see how that goes. I don't use DEQ so I can't speak on it. It does seem that you begin to roll-off at 20Hz, are you running a hpf? Are you using a minidsp 2x4 HD? Seems like you have something funky going on around 40Hz.
40hz is just the two subs having cancellation due to placement. The delay settings work best for the rest of the frequencies though. The SVS subs I tried previously in the exact same position exhibited the same cancellation. I run a HPF set to about 15hz. The roll off is just how the EQ ended up being. I would have to cut more from 20hz and up as the natural frequency response of the drivers/box is heavily weighted towards 30hz and up (I’m cutting 10-15 dB in that range already just to get the curve you’re seeing without Dynamic EQ enabled). All of this is with a NX6000d.

I’m not sure how to get a steeper house curve as I’d have to do even more significant cuts to 30hz and above than what I’m already doing. These drivers are just so naturally weighted towards the midbass and don’t produce a flatter natural response like a UM-18 would.
 

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So, pretty much exactly what the model shows? ;)

Here's both with 1200W and limited to xmax:



When you did this comparison, were both without EQ, or both with EQ? Were they both in the same locations?
No EQ on either.
 
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So, pretty much exactly what the model shows? ;)

Here's both with 1200W and limited to xmax:



When you did this comparison, were both without EQ, or both with EQ? Were they both in the same locations?
Port dimensions play a huge role in the response curve. Adjust port dimensions until you get 22m/s on both. Unless you are already in that range.
 

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40hz is just the two subs having cancellation due to placement. The delay settings work best for the rest of the frequencies though. The SVS subs I tried previously in the exact same position exhibited the same cancellation. I run a HPF set to about 15hz. The roll off is just how the EQ ended up being. I would have to cut more from 20hz and up as the natural frequency response of the drivers/box is heavily weighted towards 30hz and up (I’m cutting 10-15 dB in that range already just to get the curve you’re seeing without Dynamic EQ enabled). All of this is with a NX6000d.

I’m not sure how to get a steeper house curve as I’d have to do even more significant cuts to 30hz and above than what I’m already doing. These drivers are just so naturally weighted towards the midbass and don’t produce a flatter natural response like a UM-18 would.

I see. I use REW to create a Filter Coefficient file and import that into my 2x4 HD. Not sure how that would work with the NX6000D. You'd probably have to manually enter each filter which I'd imagine would be a pain.
 

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I see. I use REW to create a Filter Coefficient file and import that into my 2x4 HD. Not sure how that would work with the NX6000D. You'd probably have to manually enter each filter which I'd imagine would be a pain.
I use the REW EQ filter suggestions as a starting point as well, but to get a 10dB rise from 80hz to 20hz I would need to cut about 25dB at 80hz (already cutting close to 15 dB).
 

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Port dimensions play a huge role in the response curve. Adjust port dimensions until you get 22m/s on both. Unless you are already in that range.
You didn't specify port dimensions of them, but at those volumes and tunes it's trivial to get port velocity down to 20 m/s, so I'm comfortable ignoring it for this comparison.
 

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I use the REW EQ filter suggestions as a starting point as well, but to get a 10dB rise from 80hz to 20hz I would need to cut about 25dB at 80hz (already cutting close to 15 dB).
If you're starting with a nearly flat response, I don't see why you'd be cutting that much:confused:
 

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If you're starting with a nearly flat response, I don't see why you'd be cutting that much:confused:
Not sure what you're referencing in terms of starting with a nearly flat response. Here's the two subs with no EQ filters applied (just HPF at about 15hz and LPF at 200hz). The natural response of the box shows about 99 dB at 80hz and 77 dB at 20 hz. If I add a house curve to make 80 Hz to 20 Hz have a 10dB rise then in effect I need to cut about 32 dB (99 dB - 77 dB + 10 dB) to get that effect. Just seems like a lot of cutting I'd have to do to get a house curve with that big of a slope. That would seem to just eat into the headroom I have for midbass and take away from the strengths of these drivers.
 

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I agree, boosting the low end will cut the top anyway due to the power demand down low. Stop cutting up top and just boost the low end
What's the difference between the two? If I boost 20 Hz with a PEQ filter by 10 dB wouldn't I need to reduce overall gain by 10 dB anyways? Wouldn't the net be the same as me just cutting more up top?

Either way, don't I need to set the gain structure so that the loudest it plays is limited by when clipping first occurs (at whatever frequency that occurs)? In this case, it seems like clipping would occur in the lower frequencies first (I'll run out of headroom down low before I run out up top) whether I boost the lows or cut the tops to get an overall flatter frequency response (or a frequency response with a house curve).

Or is my understanding of how this works totally off base?
 

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Not sure what you're referencing in terms of starting with a nearly flat response. Here's the two subs with no EQ filters applied (just HPF at about 15hz and LPF at 200hz). The natural response of the box shows about 99 dB at 80hz and 77 dB at 20 hz. If I add a house curve to make 80 Hz to 20 Hz have a 10dB rise then in effect I need to cut about 32 dB (99 dB - 77 dB + 10 dB) to get that effect. Just seems like a lot of cutting I'd have to do to get a house curve with that big of a slope. That would seem to just eat into the headroom I have for midbass and take away from the strengths of these drivers.
Firstly, it appears that you may have negative summation with your subs. I'd definitely look into that. Just seems as you're way down at 20Hz and obviously something wrong at 40Hz.
 

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Discussion Starter #52 (Edited)
I was able to set-up the speakers and sub today. For the most part, it seems that I have a good response in my room. I had a peak between the low 30's and 40hz and a dip in the mid 80's, but not too bad. I decided to use the antimode which reduced the peak but the dip remained. After trying several crossover points and adjusting the delay on the sub (increased from 12ft to 15ft), that dip is gone. After I did the sub EQ and used the test tones CD (16hz-120hz) with the Radio Shack digital meter, this are the readings I got at my listening position with the crossover at 120hz. If someone wants to put this on a graph, feel free to do so. Also, it looks like the low end could use some boost to make the response flatter, right?

HzSPL HzSPL HzSPL HzSPL
16-67 28-66 50-74 90-77
17-66 30-70 53-72 95-75
18-66 32-72 56-72 100-73
19-65 33-72 60-77 106-75
20-66 35-71 63-77 112-71
21-66 37-71 67-77 118-68
22-67 40-74 71-78 120-68
24-65 42-75 75-77
25-65 45-75 80-78
26-65 47-75 85-75
 

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Discussion Starter #53
I also plan to give the subs a bit of a workout tomorrow with music (CD's with 80's music) and some bass heavy movies.
 

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Discussion Starter #54 (Edited)
I also want to add, if you have not tried it, to place the driver facing the wall, at least with sealed subs. It does not look as good since most people want to look at the drivers but it might improve your response, specially around the crossover region, it did with my subs. The dip now was a lot smaller and the upper bass response is a little smoother too. I'm comparing the results with previous subs I had in the same location as this ones (front corners) with the drivers on those other subs facing the listener.
 

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We all know the characteristics of sealed V ported cabinets. Yes, eventually a sealed cabinet will beat the ported cabinet somewhere between the port tune and 10Hz (ish). That's not what I mean by not better than the UM in low end. Let me rephrase that.

In my personal test, I used several songs that I always use. Songs that I know what sound like in MANY different cabinets, drivers and alignments. When LefLeppard has no real chest slam from the UM18 full marty, but the LaVoce feels like someone sitting on your chest, I say "the LaVoce sealed will best a UM full marty". When The low note in On My Level is missing in the sealed LaVoce but makes your nose tingle from the UM18 full marty, I say the UM full marty will best a sealed LaVoce. For me, although yes there is plenty of sub 15Hz content in music, the vast majority that I like is in the high teens to maybe high 20s. The LaVoce sealed, in the cabinet I used, just didn't have any authority in that range.
I thought you compared sealed vs sealed. Ported vs sealed is never fair unless having enough sealed to have the same SPL around tune but then the sealed has much more output every where else and costing 3 times more.
 

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Discussion Starter #56
Due to other things I had going on and people being home, I was only able to test the subs for a very limited amount of time. I did not push them close to their limit. Having said that, I can say that this drivers are the real deal, specially if you value music and mid-bass. By far the best I've experienced, they play loud and are clean/detailed in their presentation. The low bass is very good too, there is stuff shaking in my living room that I have to tie down. So far, they are a great upgrade over the JBL's I had before, specially the mid-bass and those subs were very good for mid-bass. I also feel the low bass is slighly improved but I need to do further testing, specially at reference level volume.

If you have the space, putting this drivers in ported boxes or devastators like most have done in here will give you all the low bass you want and even more mid-bass. I'm running the subs 5-6db's hot. My Speakerpower amp is moving this subs with authority, is still to early to tell buy my guess is that I have all the power this drivers need, specially down low. I plan to do more extended tests in the next few days or so I hope.
 
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