B460 - The Twins

[RedCoat23]

So I'm currently making progress on my mirrored B460 clone to go with my original. I used the plans on the site for my measurements and 1inch ultralight mdf for material.

I still have quite a lot to do. Only the base is currently dowled and glued, the rest is just a dry fit to see how it looks.

• Trimming for dimensions - either the values in the library postings are incorrect or my cutting isn't exact, but it looks like I have a 3mm difference in one piece.
  
  • Even larger; the base section is marked as 76mm in the plans and yet my original is 94mm, so I'm going to have to cut a new base frame. (I want them both to match).
  
  
• I have to make the 11 degree cuts to my front panel and chamfer the base and top piece to match.
• The internal bracing pieces are not yet done
• I have the pipe pieces but not yet cut and I'm going to include a cut out frame for support to the pipes inside the cab.
• Obviously veneer to be done yet too - going for walnut to keep it traditional.

But it's coming together

[Mr. Widget]

So I'm currently making progress on my mirrored B460 clone to go with my original. I used the plans on the site for my measurements and 1inch ultralight mdf for material.

Beautiful!

A pair of those will be amazing and having them mirror imaged will definitely look cool.

The internal bracing pieces are not yet done

I'm not sure what the originals used, but I would recommend KD 2x4s and as many as possible. You might also want to add a bit of mass to the walls before you add the fiberglass. A mineral filled mastic of some type should do it. Years ago I used the ultra light MDF because it was easier to work with and I definitely noticed that the cabinet was not as dead as traditional MDF.


Widget

[JBLP]

Good job!
I'm very interested in "the making of".
I will follow you.
Paul

[RedCoat23]

Thanks Widget,
I'll bear that in mind when it comes to bracing the interior. Ultralight was all that available in 1inch at the time, but was a lot easier to move

I'm having a look at some choices for wall dampening, will be easier to apply before I fully assemble all the pieces. Will update the thread again at the weekend, no time to work on it before then.

Best Regards

RedCoat

[audiomagnate]

I didn't know they made an Ultralight. I've always thought the 460 was beyond cool. I'd love to have a few.

[RedCoat23]

Update.
Well work is in crazy mode right now and I'm doing 7 day weeks, so I've had no time to look at this since my last posting. It's likely to be this for another few weeks yet.

I didn't know they made an Ultralight. I've always thought the 460 was beyond cool. I'd love to have a few.

I love the sound of the single B460 I have now. It's powered from an Emotiva XPA-1 monoblock via a minidsp. The 500w is plenty . My mains are 4412a's, but I'm trying to consider what else I should pair the subs with once finished. (Other than a 250 or 250ti that is)

[rdgrimes]

Update.
I love the sound of the single B460 I have now. It's powered from an Emotiva XPA-1 monoblock via a minidsp. The 500w is plenty . My mains are 4412a's, but I'm trying to consider what else I should pair the subs with once finished. (Other than a 250 or 250ti that is)

Pair them with anything you like.

The nice thing about multiple subs is you can experiment with placement. Resist the temptation to put them where they look best, (they are beautiful). Especially in a large room, start with them on opposite sides.

[RedCoat23]

Life has a habit of getting in the way... Anyway after a very long hiatus I thought I'd update the thread. I've spent the past 4 weekends working on the sub

First update - shows all the sides are complete and caulked. The back plate to mount the terminals was just fitted here and caulked.



Here's another shot from the rear showing the cutout



The following weekend I put in the port tubes. The next shot is the day after I'd epoxied the port tubes. These are just slightly smaller internal diameter than the original plans - 4 inches as opposed to the originals at 4.125 inches. I calculated the original volume based upon 4.125 diameter and 14.75 length. I extended the ports based upon the new diameter to 15.69 inches and I'm within 0.02in³ of the original volume.

At this stage I had not yet used the flush trim bit to clean up the excess epoxy.



Here's a better shot of the interior. I'd sprayed the interior of the tubes flat black. Note there is no bracing at this stage.



A shot from the other end. You can also see the t-nuts in place for the front baffle.



Continued in the next post...

[RedCoat23]

This is a better shot of the port side showing the excess epoxy to be cleaned up.



Finally, today's work. I was attaching the last internal brace, along with putting bondo in some areas.



For tomorrow. I'm finishing up the base. I didn't like that I had MDF (even painted) on the floor, so I'm attaching a piece of 5mm plywood to the base. I plan on sealing the footer area with duratex and going for a smooth finish.
This week I have my absorption panels for the inside arriving. I also have the fiberglass bat ready to go. Next weekend the plan is to complete all the interior preparation and do the roundover on the lid before final box assembly. Expect further updates...promise!

[dprice]

Keep up the good work! I've got a B460 though I've never really thought seriously about giving it a twin.

[4343]

Nice!

MDF is not the best at retaining Tee nuts. Give a thought to using a small piece of thin ply screwed in behind the Tee nuts. Drill holes so the bolts can pass through and screw it on between the two nuts to keep them from ever falling inside the cabinet...

I've futzed around enough with them falling inside to never want to do it again, and to know that the perfect time to make sure they can't fall out is before sealing them inside a box.

[RedCoat23]

Keep up the good work! I've got a B460 though I've never really thought seriously about giving it a twin.

Well I have a pair of 4412a's that I'm currently using with my original and there's a height difference between the speakers from one side to the other j/k, but seriously I like symmetry and mirroring gives me the option of having the ports inside or outside. Finally as Grimes points out I can use the second to even frequency distribution across the listening space. Besides it's a good exercise to engage in given I have a full set of drivers for both a 4345 and 4355 just waiting for some construction time...

Nice!

MDF is not the best at retaining Tee nuts. Give a thought to using a small piece of thin ply screwed in behind the Tee nuts. Drill holes so the bolts can pass through and screw it on between the two nuts to keep them from ever falling inside the cabinet...

I've futzed around enough with them falling inside to never want to do it again, and to know that the perfect time to make sure they can't fall out is before sealing them inside a box.

Thanks for the tip! I'll tackle that change this weekend.

I got my binding posts today along with mounting kit from dougie (t-nuts, clamps etc.) Will be updating the thread with further pictures tomorrow and Saturday.

[wrager]

Are you using the 2245 woofer? Will you equalize too? I am building a traditional 8 cu ft (net) cab with 2x6" ports using my 2245.

[RedCoat23]

Yes I am using a 2245 woofer and a minidsp to equalize - following the same parameters used in the BX63.

[Champster]

Yes I am using a 2245 woofer and a minidsp to equalize - following the same parameters used in the BX63.

Red-You're going to love these subs!!!! Beautiful build!