Is SVS PB2000 an upgrade to these DIY subs?

[rojo]

Attempted correcting using the miniDSP. It didn't do what I was expecting it to do. There are nulls even after correcting.
Did I miss out something? Could there be something wrong with my corrections file for the Umm-6?

You can't boost nulls with an EQ. You have to lower the target level so the peaks around the nulls are cut, so you end up with an overall response that's flatter at the listening position. Then you can increase the overall volume to compensate for the cuts. Think of it like mowing the lawn, then fertilizing it.

You can also try to position your subs so the nulls aren't in the same frequency for both, so that one sub compensates where the other suffers from a null, and vice versa. That's the point of running two subs -- not for more output, but for more consistent response.

Just to make sure we're on the same page, you are applying corrections to each box individually, right? You also realize that applying EQ gives you less total output and not more, right? But the quality of the equalized output is better -- more linear, less boomy one-note-wonder with unfulfilled bottom end.

If you want more output, you should consider different subs.

 

[Sylar]

You can't boost nulls with an EQ. You have to lower the target level so the peaks around the nulls are cut, so you end up with an overall response that's flatter at the listening position. Then you can increase the overall volume to compensate for the cuts.

I have lowered the target level. The measured response without EQ is better than the one with EQ. With EQ I get two massive nulls which ain't there in the initial measured response.
I played around with the miniDSP crossover and made it bypass from my initial setting of LowPass at 100Hz. When I had LowPass crossover at 100Hz I had the two nulls, but when I changed the crossover to byPass the two nulls went away. However, the measured response is still kinda ugly.

My receiver has crossover at 250Hz, and
BassSetting -> SW Mode as 'LFE+Main' with LPF for LFE at 100Hz.

Just to make sure we're on the same page, you are applying corrections to each box individually, right?

Am correcting each output in parametric EQ in the miniDSP

You also realize that applying EQ gives you less total output and not more, right? But the quality of the equalized output is better -- more linear, less boomy one-note-wonder with unfulfilled bottom end.

If you want more output, you should consider different subs.

Currently I'm going with these subs.

 

[rojo]

If you're talking about a sharp, pointy, deep but narrow dip in the graphed response, that's not a massive null. As TLS Guy already explained, you'll never hear that sort of dip.

Try to pretend you'd never taken another measurement after activating the corrections, and tell me. How does the bass sound? Are there one or two notes that sound particularly bloated, or do the lowest bass guitar notes play with the same intensity as higher notes?

Granted, overall the bass probably has less volume, especially since you EQ'd at a lower level to boost the extension and flatten around nulls. Just raise your receiver's subwoofer output volume to compensate. If it's already maxed, then lower your other speakers' volume and crank the main volume.

With your subs set at your desired volume relative to the rest of the speakers, now how does it sound, ignoring the graphs?

 

[Sylar]

Try to pretend you'd never taken another measurement after activating the corrections, and tell me. How does the bass sound? Are there one or two notes that sound particularly bloated, or do the lowest bass guitar notes play with the same intensity as higher notes?

Refuse to accept that I got a 100$ box to let my not so reliable ear do the measuring.

I did a couple of quick tests. And it was my mains which was playing alongside the subs. I unplugged the mains completely and measured. Corrected using DSP and then ran audyssey. Here's what I got. (I ran one round of measurements. Didn't try lowering the Target Level)

Note that measured response of my subs by itself is pretty good when the mains are not playing. The DSP has little work to do after that - uses just 3 of 6 filters.
However, After running audyssey the mains seems to mess up the response quite a bit.

Anyway around that? I dunno how much can I move the fronts around.

 

[rojo]

Refuse to accept that I got a 100$ box to let my not so reliable ear do the measuring....

After running audyssey the mains seems to mess up the response quite a bit. Anyway around that? I dunno how much can I move the fronts around.

Logic is the beginning of wisdom. It is not the end.

Likewise, a measurement graph also does not tell the whole story, and is easy to misinterpret. What you see as a sharp, pointy dip and interpreting as messing up the response quite a bit, I daresay is most likely quite inaudible. Comb filters are most often too narrow to be heard. It's the bowl-shaped valleys that are of more concern.

So, now that you have measured, listen. Don't try to achieve a graph that has 0 needle-pointed dips. It'll never happen, not without some serious acoustic treatments in your room.

I had the same beliefs as you when I first started playing with REW. It took me a while to understand why, despite having the same sort of comb filtering in the 1kHz+ range of my own system, I couldn't hear the dips. Knowing what I know now, those graphed responses look pretty damn nice. And I think if you close your eyes and listen to the music, if you try to listen for the dips, you won't hear them. Or at least if you do, it will only be because you were listening unreasonably critically, and they won't be nearly as profound to your ears as they are to your eyes.

As far as changing the response of your mains, you could try toeing them in or out a few degrees, so their angles of reflection are changed. You might also try messing with their crossover point. Try setting them at 100Hz and see whether that makes a difference.

 

[Sylar]

I did some listening. Definitely didn't like what I heard.
Played around with it a bit. It was the receiver settings that was messing it up. I changed sub mode from LFE+Main to LFE and set XO to around 80-100.
Re-measured and re-setup from scratch over the weekend. Noticed that Audyssey set the subs 17dB relatively higher than the rest of the setup.

Currently XO is at 80Hz. Also added a 6dB house curve at 60/80Hz.
Played a few songs - Eric Clapton, Pink Floyd, Paul McCartney, The Corrs and a couple of DubStep. It definitely sounds much better now. It is a not as tight as I like it to be, sounds a little bloated at times.

Since its late at night I cant play loud. Need to check what it sounds at higher volume. Need to check what it is like for movies.

 

[Sylar]

Used the sub for a few more days. Equalization using MiniDSP and better subs placement helped for sure. Thanks for all the help Rojo! You definitely spent some time with me on this thread. Thanks again!!

The sub sounds better and is noticeable. However, the sub is a little muddy and not as tight as I would like it to be. When I push it, it either gets distorted big time, or my room is playing.
For music what I would really like to improve is Mid-Bass.

However, I will be living with this for now.
But for an upgrade, hopefully in the near future... I am considering building 2 new subs from scratch AND 2 mid bass units to cover 40/50 Hz to 150/250 Hz. Mid bass will mainly be for music. For movies though, I'm still undecided and need to hear a lot more.