Building an IB

**Rodny Alvarez** · **11-09-06, 11:11 PM**

FIX IT!!!!

**Rodny Alvarez** · **11-09-06, 11:17 PM**

OK guys, thanks for the help so far!!!

I decided to star with the LF1 first (2 RLp 15s) in a line array, I will listen to it first before cutting the other side. The plan is to build a box for the other two subs and move it around the room to see where the best sounding spot its going to be.
Should I build the box for one 15 o I need to built it for the two for testing?

**Rodny Alvarez** · **11-11-06, 07:22 PM**

Here some pics of the IB panels.......

IB 01.jpg

IB4.jpg

HT 018.jpg

HT 019.jpg

HT 021.jpg

HT 027.jpg

HT 028.jpg

**Rodny Alvarez** · **11-12-06, 12:34 AM**

This is the measurements, the first one is subs no EQ and the second one with filters.
I'm confuse about whats happening at 65 and 98 Hz after applying the filters, can somebody tell me what's going on?
I'm using the ECM 8000 mic and UB 1002 mixer.http://www.behringer.com//UB1002/UB-1002_top.jpg

ib sweep.jpg

sub filter.jpg

Slide1.JPG

**Otto** · **11-12-06, 07:44 AM**

Hi Rodny,

Your plot looks pretty good! Nice job. Unfortunately, I can't answer about the changes in FR after applying the filters. I also see that sometimes -- a sharp dip after EQing.

**Rodny Alvarez** · **11-12-06, 05:17 PM**

More pics....

HT 033.jpg

HT 035.jpg

HT 036.jpg

HT 037.jpg

HT 038.jpg

HT 040.jpg

HT 042.jpg

HT 043.jpg

HT 044.jpg

HT 045.jpg

**Rodny Alvarez** · **11-12-06, 05:18 PM**

HT 046.jpg

HT 047.jpg

HT 048.jpg

HT 049.jpg

**Sonnie** · **11-12-06, 09:22 PM**

Awesome!

I can't wait to hear them myself.

I'm not sure what's up with the dip at 65Hz... unless you moved the mic between measurements or something else changed in the room somewhere. Did you sneeze or something...

That could go away once you add the other two drivers.

I wouldn't worry about the one at 98Hz since your x-over is at 80Hz.

So, how does it sound with just the two drivers?

**Rodny Alvarez** · **11-12-06, 10:51 PM**

Quote:

Sonnie wrote:

Awesome!

I can't wait to hear them myself.

I'm not sure what's up with the dip at 65Hz... unless you moved the mic between measurements or something else changed in the room somewhere. Did you sneeze or something...

That could go away once you add the other two drivers.

I wouldn't worry about the one at 98Hz since your x-over is at 80Hz.

So, how does it sound with just the two drivers?

Thanks Sonnie!!
I think it was a mosquito fart

I just finish reading the tread about setting the mic ECM800 and the mixer and I have to re check every thing, probably tomorrow, I don't think is right.
Its sounds good but not what I want, need to fine tune it, its a little boomy, Need to do a house curve.
Wacht some scenes of Black Hawk Down and it was pretty impressive, there was a lot of air moving when the helicopter was taken off.

I want to finish the LF1 first before building the right side, the front panel its going to be wood and fiber glass and 1/2" plexi around the sub with some lights, want to paint it black and spray some clear.
Maybe Walter let me work on it this week.

**SteveCallas** · **11-12-06, 11:03 PM**

Now that's a nice FR

Regarding the dip, did you open or shut any doors inbetween the measurements? I seriously mean any doors at all - opening and closing various doors in my apartment will affect my FR, and it is very repeatable, it's no fluke.

**Rodny Alvarez** · **11-13-06, 08:01 AM**

Quote:

SteveCallas wrote:

Now that's a nice FR

Regarding the dip, did you open or shut any doors inbetween the measurements? I seriously mean any doors at all - opening and closing various doors in my apartment will affect my FR, and it is very repeatable, it's no fluke.

No , didn't open any doors.
I'm going to check all the connections tonight and re measure again.

Thanks!!!

**jagman** · **11-13-06, 03:44 PM**

Nice pics... and a very nice plot. It's amazing how easy line array Ibs are to install. After you recheck your measurements, try manually applying all of your filters (don't let REqW set them). You should have no problem keeping the response between 10-16Hz at 80dB and you have room for a nice house curve. Not only that, but you should be able to apply your curve without causing the troughs at 65 and 98Hz to deepen. You should be able to apply all of this without boosting beyond your original plot. If you want, you can do a small bit of boost at 20Hz covering an octive or so to make the dropoff from 20 to 10Hz a bit more gradual... just be sure to watch the woofers and be careful of overexcursion.

**Rodny Alvarez** · **11-13-06, 09:31 PM**

Thanks jagman!!
I check everything and its fine, remeasure and the dip at 65 still there,, it doesnt make any sense to me every time I apply a filter to the 65 dip, it doesn't change much

even when the gain is 8 or 10, I'm just going to ignore it
I look at the graph LF1 (SVS sub) and the dip is about 68hz.

HERE more pics of the front panel...

IB panel 002.jpg

IB panel 003.jpg

IB panel 004.jpg

IB panel 005.jpg

IB panel 006.jpg

IB panel 007.jpg

IB panel 008.jpg

IB panel 009.jpg

IB panel 010.jpg

IB panel 011.jpg

**Rodny Alvarez** · **11-13-06, 09:36 PM**

IB panel 012.jpg

IB panel 013.jpg

IB panel 014.jpg

IB panel 015.jpg

Next step fiberglass resin and bondo.....

**Sonnie** · **11-13-06, 11:33 PM**

You stole my subs and now you showin' off...

**Darren** · **11-14-06, 12:57 PM**

You might want to consider laminating 2 layers of 3/4" MDF instead of the one layer I see there. The drivers may very well destroy what you have there, might be ok but better to be safe than sorry. Although the fiberglass may give you enough reinforcement...

**Rodny Alvarez** · **11-14-06, 04:20 PM**

Quote:

Sonnie wrote:

You stole my subs and now you showin' off...

Don't call the police!!....

**Rodny Alvarez** · **11-14-06, 04:34 PM**

Quote:

Darren wrote:

You might want to consider laminating 2 layers of 3/4" MDF instead of the one layer I see there. The drivers may very well destroy what you have there, might be ok but better to be safe than sorry. Although the fiberglass may give you enough reinforcement...

There is two pieces of 3/4 MDF allready, plus the front panel is 1/2 MDF plus the fiberglass and 1/2 plexiglass, it will be about 2 3/4", I think thats plenty.
The wall is only 56" tall, not like every body else, they have a 8' or 10' tall.

**Sonnie** · **11-14-06, 04:49 PM**

I only see one layer of MDF in those pics above.

**Darren** · **11-14-06, 04:50 PM**

Quote:

Sonnie wrote:

I only see one layer of MDF in those pics above.

Yeah, that's what I saw... I'm confused.

**Sonnie** · **11-14-06, 05:05 PM**

Rodny's been sippin' on something... or is it that whacky weed... lol

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