My Behringer B2030P Project

[sholling]

I just thought I'd share some pictures of my progress on this project. Please note that this is an experiment and that I'm a beginner at modding speakers. However I do have an mechanical engineering background (however my degree is in IT). Anyway I decided I'd take on a Behringer B2030P project after reading JerryLove's glowing reports and studying up on WmAx's suggested modifications. I started out with the woofer and tweeter fixes and lived with just those for a few weeks while I pondered WmAx's suggestion to replace the stuffing with something better and more of it. Since I couldn't seem to find the suggested product I decided to experiment with something that I've used for soundproofing projects.

These are two views of the cabinet before my changes.

These two are with the stuffing removed.

 

[sholling]

Since I could not find the suggested material I decided to line the box with high density closed cell acoustic foam. This isn't the cheap stuff that parts-express sells for subwoofers. This foam is much-much denser.

Here I've lined the back of the cabinet with 1/2" foam and stuffed the spaces on both sides of the port tubes with 1/2".
I then removed the remainer of the old hot melt glue before proceeding.

Here I've inserted a U shaped length of 1/2" foam around the top and sides of the cabinet.

Here I have a piece of 1/2" foam along the bottom of the cabinet. Although you can't see them in the photo the ports are not blocked or impeded.

At this point I'm just doing listening tests but so far happy with the results. I'll decide later if I want to invest in a calibrated mic and test software. I'm sure there was a better method or material to use but this seems to do the job.

 

[skyline_123]

Looks like fun. Keep us updated! Can't wait to hear your impressions.

 

[sholling]

Typo correction: The foam on the back of the cabinet is 1/4" thick. Everything else is 1/2".

 

[WmAx]

Non optimal material.

PM me and I'll mail you a small bit of the right material; enough to do the project.

-Chris

 

[Quilope]

Hello, sholling.

Thanks for putting up pics of your project! It's always so much easier to be able to SEE things - not just read about them.

I am thinking about buying a pair of B2030P's, and I have been reading about modding them. WmAx wrote a little blurb about it, and put in some different modification options - some of which seem rather complex. "Step 6" in particular;

6) OPTIONAL MODS: Use a hammer and block of wood and knock out the ports. After you remove them use black silicone and small piece of wood from behind the port openings and block/seal them. Now, apply Dynamat or similar material to all inner walls. You do this before installing the new acoustic absorption material. Use a thickness equal to 1/3 the wall thickness minimum. That is, the walls are 3/4" thick; so you will use layers of Dynamat or similar until you build up to a minimum of 1/4" thick. Do not go beyond 1/2" thick. After 1/2", you will no longer get much more dampening. For optimum dampening, you can use what is called a constrained layer. In this case, apply 1/8" thick Dynamat or similar to walls. Now use an appropriate adhesive and apply 1/2" concrete board to the Dynamat. This creates two stiff plates(concrete board and exterior MDF) that will cause greater molecular excitation in the Dynamat, as a result of sheering type forces. You can go further and use some 5/8" all thread rod and cut it about 1/4" short of the concrete board to concrete board contact points across the enclosure. Use nuts on both ends of the rod. You will use the nuts to take up the slack and grab the inner walls. Use peramanent locktite on the threads to lock the nuts(you will have a few minutes open time) and use high quality metal epoxy to adhere the nuts to the concrete board. If you use the all thread bracing technique in more than one axis, try to have the all thread rods intersect with each other and use more of the metal epoxy to bind them in the middle of the cabinet; this will make the bracing stronger.

He's banned, so I can't ask him about it. I'm wondering how much of a difference all this makes? Also, from your pictures, I can see that it is easy to take off the molded waveguide part off the front of the speaker. If I were going to try to put cement board inside of the box, how would I get it in there? Does the whole front board come off the speaker? I would guess that it's something like MDF and it's glued to the side, top and bottom boards. Also, Dynamat is expensive!! Not only is it pricey, but I've read that the adhesive doesn't always stay stuck. I'm wondering if the less-complicated, less-expensive route will still help me to get the most out of my B2030P's?

Did you do any of the other stuff he recommended, like the rope caulk/super glue/silicone sealant tricks? It seems pretty easy to me, I'd just REALLY hate to screw up my brand new speakers...

 

[sholling]

I redid mine after those pics. I replaced the stuffing with as close to 2" of Roxul that I could glue in there and still leave room for speakers and the ports to work.

 

[Matt34]

Hello, sholling.

Thanks for putting up pics of your project! It's always so much easier to be able to SEE things - not just read about them.

I am thinking about buying a pair of B2030P's, and I have been reading about modding them. WmAx wrote a little blurb about it, and put in some different modification options - some of which seem rather complex. "Step 6" in particular;



He's banned, so I can't ask him about it. I'm wondering how much of a difference all this makes? Also, from your pictures, I can see that it is easy to take off the molded waveguide part off the front of the speaker. If I were going to try to put cement board inside of the box, how would I get it in there? Does the whole front board come off the speaker? I would guess that it's something like MDF and it's glued to the side, top and bottom boards. Also, Dynamat is expensive!! Not only is it pricey, but I've read that the adhesive doesn't always stay stuck. I'm wondering if the less-complicated, less-expensive route will still help me to get the most out of my B2030P's?

Did you do any of the other stuff he recommended, like the rope caulk/super glue/silicone sealant tricks? It seems pretty easy to me, I'd just REALLY hate to screw up my brand new speakers...

If I remember correctly, to do those mods you would have to cut the back side of the speaker completely out.

 

[jp_over]

I redid mine after those pics. I replaced the stuffing with as close to 2" of Roxul that I could glue in there and still leave room for speakers and the ports to work.

Is it possible for a brief post-mod review for those of us with inquiring minds?

 

[sholling]

Is it possible for a brief post-mod review for those of us with inquiring minds?

I haven't listened to the Behringers, either modded or unmodded, in 6 months. Not since I bought the EMP E41s. I still have the three of them (and two more in never opened boxes) stored out in my shed. The stuffing gets rid if the very slight hollowness I hear in the stock speaker and tightens up the mids a bit. Unfortunately the B2030Ps aren't the bargain they used to be. I've never run a frequency response test and it's been a while since I've listened but I liked them a lot for the price. BTW one sheet of 2" Roxul and one large can of 3M Super 77 spray glue is enough for 3 speakers. A small T-square, long-blade utility knife, and a very sharp 6" fillet knife (for beveling) make the job easy. I can't seem to find the speaker caulk/putty that WmAx suggested to seal the tweeter against the wave guide but it was like $1 at PE - it might have been this.

IMO for a near field speaker they're still well worth the money at $160/pr but before I'd spend the $220/pr that some shops are asking I'd save a bit longer for b-stock Ascend CBM-170SEs while they last. To me the 170SE a big step up to something I feel is roughly on the level of an Usher S-520.

Anyway here are two quick cell phone photos. Note that the side stuffing is 1-2" thick at the bottom but has bevels carved around the openings to make room for the drivers and openings are left at the bottom sides for the openings to the port tubes. The back stuffing is 3 or 4" thick and there is a channel left open between the tweeter and the woofer.

 

[darien87]

Looks like you stuffed it with oatmeal.

 

[sholling]

Looks like you stuffed it with oatmeal.

Roxul ain't pretty. I kind of wonder how Black Hole 5 would work. Of course that stuff is so expensive (~$25-30/speaker) that it's not practical and you might still need some additional stuffing. Not my area of expertise and I know I'm not putting any more money into them.