4 T48s and 2 Cosyne synergy horn: Canberra Oz

[marko]

Hey guys,

Been too busy building cabs to start a thread but thought I should get one up and running (the missus has put a 9pm curfew on power tools for the sake of the neighbors so what else am I going to do with the long cold evenings?)

We have been plugging away for the last few weeks now and have recently started to see the fruits of our labour! What was a whole pile of ply and sawdust can pretty quickly turn into a cab which is nice. No major stuff ups yet- and our time getting accurate cuts has paid off with a relatively issue free construction phase. Lots of reading and re-reading the plans, figuring out sketch up models and making lists (I'm a list kinda guy)

A few basics- we went with the Ande 15" driver- 12kgs a pop but with all the right looking specs- not to mention an ok price too! For the cabs we ended up going for a 24" wide (25" wide total) Cab made from a mix of the regular bunnings radiata cd ply and the marine grade hardwood ply. Radiata for the inside panels and braces, hardwood for the external panels. These cabs will win no lightweight competition- but hopefully the added timber density will help resist the cabs from denting/ scarfing when they get smashed around in transport/ getting hauled into the forest for a doof). With the plans we went for a 1/2 square back 1/2 angle back approach. I liked the handles on the top and wanted to keep that feature but also liked the shape of the angle back for the bottom. We have installed small pads for casters to go on on this panel and it seems to work really well. I looked at converting all the measurements to metric for this build but decided it was too much hassle. All my rulers, table saw and tape measure have both so I just paid attention for the first few days and now it's like 2nd nature.

We used the sika supergrip 30min construction adhesive for the first 2 cabs as the PL got lost by the freight company and it was actually really nice to work with. Best approach was to let it dry in beads then come along with a sharp chisel once it had set and get if off in one go. Our first few attempts at wiping it off as we went just left more chiseling/sanding work down the track.

In terms of the build I've got 2 of the T48s pretty much done. Got the 2nd side dry fit together to check for square/countersink screwholes and will be taking it apart for painting up into the throat. Still need to install speakon connectors and the driver cable. After that it is final filling, sanding and painting time. We are hoping to do something a little different with the colour scheme for this system- meaning the final steps are a bit funny. We want the front braces and the cab outer to be the same colour with the horn throat a different one. At the moment I think the best approach is to paint the throat with a couple of coats, then sinal install the 2nd side, fill and paint the outside, then install the separately painted brace module at the very end with some judicious sika (because if dries white) and a few brads. And by the way, how awesome is a brad nailer?!! never used one before this project and it has made all the difference for us. Quick, accurate and very versatile.

We are still chasing down a limiter and a big roll of cable to make our leads but hopefully we can get them working in the next few weeks!

We went out to a music night the other night at a local bar- Nosaj Thing and D Tiberio played (Horizonize supported). The kludge of a system they had rigged up was pushed to its absolute limits and took up a huge amount of floor space in a relatively small bar. Kinda encouraged me that what we are building will find its home in the local scene. On a side note- also been looking at unity/synergy horn designs that we might be able to build to pair with our system as monitors (the djs/artists need good sound too right?)

Anyway, bed time for me. Hope you enjoy the pics- will post more as we get further along. Feel free to drop comments/ ask questions.

[Grant Bunter]

Looking great so far!

In that second pic, the cab shows a black grainy area on the left side inner edge.
Is that a void in the ply or just a stain?
If it's a small void, put a smear of Sica/PL into it to ensure the innermost ply stays secured, ie, stop it delaminating...

[bitSmasher]

As mentioned previously, really keen to see how these fare. Will definitely make an effort to get to a gig when all 4 are in full force

Great idea using the cheapo ply internally, I've found it's pretty soft and wouldn't survive regular gigging... but for ~$35 a sheet, that's expected

how awesome is a brad nailer?!! never used one before this project and it has made all the difference for us. Quick, accurate and very versatile

Oh yeah! I bought one myself last Friday - Ryobi 18v thing. I knew it'd be useful but held off for over a year... wish I had bought it sooner, it allowed me to bang together a mockup box on Saturday in 1/4 the time of drilling/screwing. And you can pry apart errors and start again with minimal mess. And you can run a router roundover through brads without causing as big a distaster as screws would.

[escapemcp]

Oh yeah! I bought one myself last Friday - Ryobi 18v thing. I knew it'd be useful but held off for over a year... wish I had bought it sooner, it allowed me to bang together a mockup box on Saturday in 1/4 the time of drilling/screwing. And you can pry apart errors and start again with minimal mess. And you can run a router roundover through brads without causing as big a distaster as screws would.

Me too... £17 from Lidi (discount supermarket place that has offers each week on hardware). Haven't actually used it yet though!! I'm worried that after shooting a brad, if it doesn't go all the way in, what then?? Hammer? Dremel to cut it off?

Routing through screws is great fun though (although definitely not recommended). I just take it slow and it's like my own fireworks display! My (very cheap) bit has eaten it's way through multiple screws without any ill effects (don't know how much longer that could have continued - but it'll be all right now that it only has to chomp through brads!)

[Grant Bunter]

I'm worried that after shooting a brad, if it doesn't go all the way in, what then??

Nail punch and hammer, knock it in until it's under the surface of the outer ply.

Sorry for the sidetrack...

[marko]

Hey gang,

So just a quick update. The cabs are coming along nicely, hopefully will start the painting process this weekend if the weather is nice to us. There is a gig coming up on the 3/8/2014 with bass master 'Teebs' from flying lotus's brainfeeder label (that LA bass vibe) that we might approach the organisers about and offer the titans for the low end- just to stretch their legs y-know. Depends on the space, but 2 of them v plated in a good corner should compete with the kludge systems that usually get thrown together for these events.

I've just made a list of the outstanding things that we need to do to get them firing to keep the process fresh in my mind
1) install access cover braces
2) countersink some more intermediary screws on the 2nd side now that I know it aligns
3) Install and seal driver wire
4) Install 2nd side
5) Paint front braces (modular and away from cab- due to colour scheme)
6) Clean up squeeze out from 2nd side and paint throat- 2 coats
7) Bog and sand screwholes on 2nd side
gasket install and leak check
9) install t nuts for v plate
10) Duratex time!
11) install speakon connectors
12) Install Chevron corners
13) install front brace- tidy up excess glue and touch up paint
14) Re-install casters
15) make sweet bass frequencies and beach some whales.

Just a quick question on the v plate- if you laminate 2 pieces of 12mm radiata ply together, does it end up being stiff enough for things to be sat on top of it- IE- stands with a monitor speaker etc. How about if some bird wants to get up and dance on it etc? Alternatively, there is some free 16mm MDF in town at the moment that we might be able to use for it- probably heavier and less stiff.....but free is always tempting.

Any thoughts with my list and things that we may be missing? Will get some pics of the progress we make over the weekend.

Cheers,
Mark

[Tom Smit]

You could try something like in this link..... http://billfitzmaurice.info/forum/viewt ... =1&t=21158

[Titanium Hand]

Nice to hear you guys got your build underway You won't be disappointed. I'm actually pumped to come and hear the four of them myself - given they are 'The LOUDEST' >100Hz cabs in the range.
Bummer about the PL, sika is

[horizonize]

Some more photos of the build.

Should finish this weekend with warm weather and some Duratexing.

Grant - the dark spot in one of the first photos is not a void (thankfully - it would have been a PITA to bog) but just the black and white doing wierd things with the grain.

Still thinking what level of bracing for the V plate. I don't think we will get too carried away.

[horizonize]

more photos

[horizonize]

more photos

[horizonize]

leak tested and no sign of any problems so far.

we thought we had to large an access cover brace when we tried to place them in over the 30hz sine waving drivers, but it was just the air pressure - pretty much had them levitating. no cone slap.

wiring went fine. we went for the most straight forward placement between handle cutouts. should be able to loop the speakons through and around the handles for a bit of lateral strain relief as we couldn't source cheap 90 degree connectors.

the build has gone well (too well we are thinking - will probably arse up the next set).

one deviation we have made from the plans is to build the front exterior braces as a module outside the box (after dryfitting and gluing bradded in) so as to make painting the mouth easier.

we are going for a black with a white mouth scheme with black braces. once the white is looking nice we will brad and glue the braces back in, then finish tidying up the squeeze-out and spot paint as necessary.

getting excited. still searching for the right speaker processor....soon though..soon

[DJPhatman]

You should not have painted where the braces will glue on. Doing so may interfere with adhesion. Mark where every joint will be PL'd, and sand or chisel to bare wood.

[Tom Smit]

You should not have painted where the braces will glue on. Doing so may interfere with adhesion. Mark where every joint will be PL'd, and sand or chisel to bare wood.

+1

[horizonize]

Noted. Will chisel on the weekend