New Active OB Build

[DQ828]

Been busy playing with the Arduino stuff. I swear I couldn't have made these speakers any more difficult to build, anyway getting there slowly.

Edited September 12, 2012 by DQ828

[DQ828]

Thanks to Mister Plywood cutting the mitres out of square, the box has ended up slightly smaller than planned & the bass driver wont fit in the box with the rubber surround on it. The rubber surround isn't absolutely necessary but I would have preferred to have it in place.

If you ever think about buying or making a router table, GO FOR IT, it has so many uses.I use mine as a joiner as well, although the jointing width is limited to the length of the cutting edge in the bit, You'll never use a plane again to straighten an edge once you have one of these & a good bit.

[DQ828]

I've been beavering away getting things done slowly. The boxes are finished ready for painting. The "Men" are largely finished, although I expect the finishing touches to take a while yet. I have finalised my plan to make the grill cover surrounds, they will be laminated up using three pieces of 4mm ply with the left over carbon fibre between the ply to add stiffness. I made a test piece which is a strong as you could hope for.

I have been having fun making a test leg for the speaker boxes, the final legs will be made from Tasmanian Blackwood the same as the thick veneer on the Men faces. It took a while to devise a plan for the leg construction, I'm glad to say the plan seems to have worked ok & I have learn't a few lessons on the way. The leg is made in two halves & only glued at the top & bottom so it will be easy to cut out the middle section, I laid some baking paper between the non glue section so any glue that seeped in wouldn't glue the pieces together where I didn't want glue.. The threaded rod doesn't actually run all the way through, I have cut a nut in at each end inside the leg which will come out when the middle section is cut out of the leg. The leg was roughed out on the router table & fine tuned with the trimmer.

I have recessed acorn nuts into the Men bases so the Men can be bolted onto the boxes.

I have settled on a paint system for the boxes, which will be.

* Two Pack Undercoat

* Single Pack K&H Fine Bumper Texture

* Colour is from an Alfa & Is called Bronze Metallic.

* Acrylic Automotive lacquer Topcoat

I had intended on using all 2 Pack (2K) but could not find a texture that I could put 2K over. I haven't done a sample of the texture yet so that could still be abandoned. I want a low sheen finish.

Ideally I wanted the colour to match my amps which are powder coated with Interpon "Asteroid" texture. Interpon do make a paint the same colour, but it costs a fortune & it is 2K, so it wont go over the texture.

I'm hoping to have this lot finish for Christmas.

Edited October 4, 2012 by DQ828

[DQ828]

I'm thinking maybe the leg is a little too fat.

[SteveLuck]

Full marks for technical effort, execution and individuality. Very impressed with the routing set up and jig for doing the legs - i think they look good. If you don't it's probably because your a bit to close to the project now - step back and ask some mates.

It's a lot of fun and very different but not unatractive - i'm warming to it.

[DQ828]

Full marks for technical effort, execution and individuality. Very impressed with the routing set up and jig for doing the legs - i think they look good. If you don't it's probably because your a bit to close to the project now - step back and ask some mates.

It's a lot of fun and very different but not unatractive - i'm warming to it.

I'm glad to hear somebody is warming to it

I think the step back suggestion is a very good one thanks.

[L J T]

Very individual design indeed. You have put some great skills into this build. How did I miss this build ?

Following with interest. You have a very good router setup also. I think it is the most versatile tool in the workshop and you are showing what can be achieved with it.

[hochopeper]

I think the leg looks in proportion, too skinny and it would look wimpy!

[DQ828]

Thanks for the input guy's.

I have a slight flat spot near the top that you cannot see in the photos', I am going to print out a couple of slightly different shapes, pick one, & make one more test leg on the weekend.

The router table is great, very versatile, weight's a ton though, I got a bit carried away with the materials when I made it.

Edited October 8, 2012 by DQ828

[LogicprObe]

Great thread and a great project!

[DQ828]

Progress has been slow, it's not from a lack of trying though.

I have now made three prototype legs & modified one of them to finally arrive at a shape I am happy with. Now all I have to do is make eight more, why eight if I already have one I'm happy with, well it turns out I'm not happy with the colour of the Tasmanian Blackwood I bought from the local supplier. It is too blond and will not give the appearance I am looking for. When I bought the wood I compromised, because the next supplier about 160klm away. Once I had seen the finished (Blond, see photo) leg I knew it wasn't right and would only annoy me for the rest of my life if I didn't change the timber. Each leg takes at least half a day to make so I still have a long road ahead.

I have sprayed the base boxes with 2k primer, the next step for them is to spray them with K&H Bumper Texture coat & then with automotive acrylic enamel. The color is from an Alfa and is called Bronze Metallic.

I have spent the last day & a half joining the Mid driver section to the tweeter driver section, it turns out the CNC router didn't cut the recesses as I expected, it was surprisingly difficult to get everything to line up properly.

Hopefully I will get the speakers finished over the Christmas break.

I still haven't decided what to do for feet, the speakers have to be about 35mm off the floor to accommodate the speaker connections which will be under the bass box, spikes are out, I'm not a fan.

[DQ828]

I have been pondering what type of cable to use to connect the drivers to the speaker terminals at the bottom of the Bass box. Because of all the effort I have gone to, I thought it would be nice to use a good quality cable, I don't want to break the bank though.

All suggestions are welcome.

the recess for the cable either side of the mid driver is 3.9mm wide so the cable can't be too large

[DQ828]

I don't think it's ever going to end!

I had just finished spraying the texture coat on the base boxes when I found a blob of something on one of the sides that was still wet, and of course it wasn't on the bottom. Initially I managed to get get most of it off, but when I tried to get that last little bit off, it turned into the disaster you see in the photo. There's always tomorrow I guess, I was hoping to spray the topcoat tomorrow.

[DQ828]

I did the respray today & am happy to report all went well.

Originally I was going to spray the colour coat on all surfaces but have decided to only coat the outside of the large boxes as that is all you will see once the grill covers go on.

[DQ828]

While I was at the auto shop buying the paint I saw this De-nibbing tool & sanding pads

, great idea but a bit expensive so I made my own which I will use in my Dremel.

I used an old dremel bit, Araldited on a Western Red Cedar disc, which was cut using a sharpened piece of SS curtain rod, I then sanded the disc so it was perfectly round, coated the end of the in Araldite, stuck on a piece of self adhesive hook & loop, cut a disc of P1500 grit hook & loop paper & $350.00 was saved, the $350.00 doesn't include the pad larger disc sander in the clip.

[DQ828]

The new & improved version

[DQ828]

I managed to spray a couple of coats of finish on the external base boxes, the colour is darker that I expected so I am holding off putting more coats on until I'm ready to put them together, by them I'll have decided whether to change the colour or stick with what I’ve got. The looks black until you put them beside the inner boxes which are black, then you can see the slight gold in them. The metallic gold sparkles beautifully in the sun, but they won't be spending anytime in the sun .

I planed all of the legs ready for routing & managed to get two done, the second leg took 65min just to do the routing, without stopping. The first one took longer! Only six & a half hours of routing to go Then they will need lots of careful sanding, 1% inspiration, 99% perspiration.

PS: If you look at the bottom 2 holes of the box you will see where a wasp made a home for some eggs while they where drying, needless to say they wont be hatching.

[DQ828]

And then there was 8, and a big pile of shavings

Lots of sanding next

[DQ828]

Still plugging away, the legs are sanded & have a coat of oil finish on them, I intend on putting a couple of coats on before I fit them to the boxes.

I have changed the finish from a brush on lacquer, to the wipe on oil finish because I wasn't happy with the lacquer finish I had already put on the MEN. It's a finish I've used many times before but this time it wasn't doing it for me. This of course means I have to remove the lacquer I have already applied, yeah I know "my own worst enemy".

I think I have already mentioned I wasn't completely happy with (is this man ever happy) the colour of the boxes, too dark & not enough sparkle, well now I have a small tin full of Gold Pearl to play with, this could really stuff things up

I've ordered some 1/4" brass coach bolts to screw into the bottom of the legs to act as adjustable feet.

Edited December 16, 2012 by DQ828

[DQ828]

Well a little bit of Gold Pearl goes a LONG way. Initially I put 10ml in with 150ml of colour & it was way too much, I ended up using 5ml & I'll have to say the colour is just about perfect. Originally I wasn't going to put clear coat over the colour but it marks really easily, I think it has something to do with the texture as well. Does anyone know if you can put water based acrylic over automotive acrylic 1K lacquer?

If I had my time over I would do several things differently, wouldn't we all!. First I would have stayed with the original plan & used a metal bracket to support the bodies as was the original plan. I went away from the metal bracket as I would not have been able to make them myself at a higher enough quality. In retrospect I should have forked out the money & paid a professional to make them for me, as going to the carbon fibre alternative (which works just fine) has added an enormous amount of work. I would not do the box within a box as it has also added an enormous amount of work, it was done to keep the box size to an absolute minimum size. And last I would probably have made the base for the bodies out of stone (marble, granite?) and isolated the body from the base using some sort of dampener and not actually fixed the bodies to the box, just relied on the weight of the stone.

If I hadn't done everything twice it would have speeded thing up as well, some things I've done several times

I am using 1/4" brass coach bolts as adjustable legs for base of each timber leg.

I'll have to say I'm just about over it, but there is light appearing at the end of the tunnel now.

I am using a protection cap for the tweeters & have stolen 56's idea re the perspex brackets to hold them, I should have known anything 56 did would take forever to do, I don't think they will be quite the quality of 56's either.

Edited December 29, 2012 by DQ828

[DQ828]

Took all day to get the capacitor holders finished and I had help!

The gold bayonet plugs are 5mm & come from the model car hobby fraternity, the socket will be glued into the plexiglass holder & the tweeter + will be plugged in, in series with the speaker terminal.

The board the capacitor holder is sitting on is my test spray piece, I sprayed a coat of Mirotone Satin water based lacquer over the automotive acrylic colour & it appears to be fine, it really helps with the metallic finish shine when in the sun, I'll have to get a couple of well placed halogen spotlights for effect

I beat you can't guess what the little hexagon pieces of wood are for.

[DQ828]

It's been a very hard day at the office! After I put the primer (blue paint) on, and before I put the finish coat on the boxes I made sure they would fit together, guess what, they don't want to go together even though there is no extra paint where they join. I spent hours getting the bass driver box into one of the outer boxes. I assume its weather related, it's a lot hotter & more humid than when I did them originally. In the end I put the bass box in front of the air conditioner for an hour or so & that did the trick, of course there is the possibility the box may expand & break the outer box.

Anyway, tomorrows another day.

[DQ828]

Number 2 is almost done, I still have to make the grill covers & small covers for where the wires are terminated on the mid & tweeter.

If you look closely you'll see a couple of extra holes that I mistakenly drilled  long ago, still haven't decided what to do about them.

[DQ828]

When I put the 2nd speaker together late last night I forgot to put the infill panel in below the mid driver, so when I went down this morning to wire it up the first thing I saw was the infill panel sitting on the bench, doop.

It turned out not to be a difficult as I first thought to put in the panel. I needed to support the body so I could remove two of the bolts holding the body to the box, I thought it was fitting to use a couple of pillows to do it

I am now making the grill covers, I am custom fitting each one to ensure a good fit. I thought I would just build one first as I'm not sure how they will workout,
 

[Sierra]

So much skillfull workmanship have gone into these speakers.

Really like your attention to detail ... very impressive ... like all the work that has gone into that cap holder that will probably never be seen by anyone.

Incidentally you are using the same Jantzen Cross Cap as I am using on the bass drivers of my speakers