I prefer only to treat first reflection point as if too much broadband absorber for wall, the room might not sound lively. Also put the rockwoll in the front too.

Price check out with www.polyglass.com.my. Just mention you are contractor building a conference room or karaoke room for customer. They don't sell to end user. Last time I manage to get some ex-stock from their warehouse which is quite cheap.

Did u cut your sub at 50hz? Also, can you try to increase the volume and see what's the highest SPL you can reach? If you can get +-3db at 105db from 20hz to 80hz that this is monster sub.

If you don't cut it, then it's weird it roll off quite drastic after 50hz. Normally peak and valley due to room interaction you should have several peak and valley but never roll off in your graph. The roll off is almost 20db which is too much. Even an equalizer can't help you much here if the drop off is too much. You can try some bass trap here.

This post has been edited by pierreye: Jul 23 2009, 10:07 AM

Bass trap is to smooth down the valley and peak. It don't actually boost up valley as it only help to reduce the interaction of the wave so you have less cancellation. Did you cut your front speaker at 50hz? Normally test tone I feed through the L/R input of the receiver so that I can see how the speaker interact with my sub.

This post has been edited by pierreye: Jul 23 2009, 01:08 PM

I think this is the reason. When you cut your front speaker at 40hz and you play the test tone through the LR analog, SPDIF or HDMI, the receiver will only pass through 40hz and below to your sub. Anything above 40hz will be roll off to your sub which is why you get this graph. I would suggest you cut your front speaker at 80hz same as your sub so that you have a good blend. Even if you front speaker can go low, it is sometime not advisable to cut too low if you sub can handle it. This will give your front speaker more headroom and your receiver wouldn't have to play too hard on low freq. There is an article mention if you have multiple speaker that can play low at diff freq, eq. front 40hz, center 60hz and surround 80hz, it's best to setup all to cut at 80hz. The reason is some receiver during mixing different low level freq to .1 channel, it might have problem blending all the speaker during the freq cutover due to diff cut off.

This post has been edited by pierreye: Jul 23 2009, 07:29 PM

Good. Can you try to increase loudness and play the testtone at 20hz? I want to see how loud can this sub go. If you can reach 105db, then at USD 1k + 25% tax (less than RM 5k) is a good buy.

You will see that the db do not increase even if you increase the volume. But normally at this level the distortion is quite high. What does it mean if it can't hit 105db? Nothing unless you listen at reference level. That means your sub can't produce the dynamic sound of the movie. Eg, if you normally listen at 85db, and your sub can play up to 100db, you'll have 15db headroom. Normally movie or ochestra have a dynamic range of +-20db, meaning at the most dynamic scene or sound, your sub will not reach the max.

Normally the lower the hz, the lower the db output. Most movie put a cap at 20hz. If you can hit 105db at 20hz, I can predict the sub should be able to play higher db at 30hz - 50hz.

As for the headroom, it had to depend on your front speaker too. If you speaker can play loud but your sub can't, then you will experience lack of bass during high volume.

Guys, where to get RPG diffuser in Penang or KL?

Another option here. Just purchase the kit (come with amp, 15" Subwoofer and DIY plan).

http://www.rythmikaudio.com/DS1500ci.html

how much you want to sell? My friend might be interested.

I can see a lot of Submersive owner mention this is their final destination for best sub. Even there's an owner with twin PC-13Ultra mention submersive offer better bass quality especially in mid-bass punch. Even I'm itchy to get this. If you can get your unit safely, then I might not get the PC-13Ultra. You still need an EQ for this sub as recommended by Mark Seaton.

Even 4k more than PC-13Ultra would be worth it as this is dual 15" sub that beat twin PC-13Ultra. Twin PC-13Ultra would cost around RM 13k ++.

Your unrated version quite funny. Anyway, I got 12" didi. It's called Velodyne DD-12.

ront88, you can try out Anti-mode with submersive if SVS-EQ1 is too expensive. Should be around RM 1k. It does correct for freq and time domain.

http://www.avforums.com/reviews/DSPeaker-A...-EQ-Review.html

Only thing it doesn't measure is integration with your speaker so you still need to adjust the phase manually to blend into your speaker.

This thing is simple. Just connect the cable from your AVR to Antimode. Then connect RCA out to your sub. Plug in the mic into Antimode and run the calibration. It will automatically generate some test tone for measurement and after 5 mins it's done. If you want the second measurement, just put your mic at second location and repeat the step.

Wow... how much you pay in total including tax? I send an email to Mark Seaton but no reply until now. Must shoot him more mail.