# The last Quartet 15 build?



## ripcard

During my CLD Dynamics builds I had the idea of building a sub to complete my DIY HT setup. While doing some research on what I would build, I came across a slightly used HPSA 1000 plate amp for a great price. Since the Quartet 15 kit (http://www.creativesound.ca/pdf/Quartet15_Subwoofer_Kit.pdf) was one of the subs I was considering (it uses this very amp), I contacted Bob to ask if he would sell me the kit minus the amp. We agreed on a price and I ordered it. That was six months ago! I see now that the SDX15 is sold out. This may be one of the last builds of this design. Hope I can do it justice.

I had finally cleared my plate of other projects and recently started in on the build. I'm making a few small modifications to the recomended box. I've decided to do the internal brace a little different and recess the driver and PRs. This changed the dimensions slightly. I added 1/4" to the internal height of the box to allow for the extra volume taken up by my larger brace, and the width also grew because I added another 5/8" layer of MDF on the three sides with the driver and PRs. This should allow a solid flushmounting of the driver and PRs.

*Here is my Sketchup drawing showing the changes.*









*My brace being cut.*









*Gluing up the brace.*









*The top and bottom pieces were cut to exact dimensions and all the other pieces were cut slightly oversize. As you can see, I did the glue up in stages. This is a big box and I felt it would be easier for me to ensure square this way.*

















*In order to accomodate the overhang of the sides, both top and bottom, I used some thin strips ripped from scrap MDF on top of the pipe clamps.*









*Added the second layer on two sides and the single layer back.*

















This work was done a few weeks ago. Just getting around to starting the build thread now. I'm hoping to be able to make regular updates as I make further progress. This thing is going to be heavy!


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## mdrake

Thanks for posting those pics. Very nice work!! :T


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## RossMc

I just finished one too. However, my amp seems to rattle. Has anyone else had this problem?


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## mdrake

Just noticed the flush mounting. *Very nice touch.*

The amp should not rattle.


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## ripcard

Thanks for the positive comments mdrake. Getting a little further along on the build, so I'll show you where I'm at as I pack for a flight out tomorrow morning. This is one heavy box...even empty.

*In order to be able to do some "glue management" on the inside of the box when putting on the last side, I went ahead a did the cutouts for the PRs. This way I could reach in and ensure most of the glue stayed in the corners where it belonged, not running down the insides. This is the first of two layers of MDF for the front of the cabinet. Same as the PR sides.*










*After cutting the hole for the SDX-15, I droped it in to check the fit and drill the mounting holes.*


























*Same thing for the PRs.*



















*Then it was time to work on flush mounting the amp. I started by measuring the amp's radiused corners and using the circle jig to cut them. In this case 2.5". I then measured the distance from the edge of the router base to the bit and clamped straight pieces of scrap MDF to make a guide. The first pass gives the outside profile of the plate amp.*


















*I then cut some strips 7/8" wide and long enough to fit inside the guide frame. This moved the cutter in to where I could plunge right through to make the opening for the body of the amp.*











*Then it was just a matter of using the router free hand to remove the material in between the two cuts for a nice smooth surface for the gasket.*


































Up next is flush trimming all the sides but that'll have to wait 10 days as I'm off on vacation. Next update will probably be around the weekend of the 8-9 of May.


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## Bengoshi2000

Flush mounting the amp FTW! Looks nice. How are you planning on finishing off the box?


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## Mike P.

Nice cabinet work!


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## mwmkravchenko

Great work on the sub enclosure. I particularly like the way you cut out the internal stiffeners. That's a good way to do it.

Mark


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## ripcard

Bengoshi2000 said:


> Flush mounting the amp FTW! Looks nice. How are you planning on finishing off the box?


Thanks. I'm hoping to pull off a paper backed cherry veneer wrap with 3/4" round overs.



mwmkravchenko said:


> Great work on the sub enclosure. I particularly like the way you cut out the internal stiffeners. That's a good way to do it.Mark


Thanks Mark. I've always liked the extra strength inherent in curves and circles.

I hope to have another update early next week.


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## ripcard

Well, it's been longer than I anticipated since my last update so I thought I'd post up what little progress I've made.:sad: Time to work on this is in short supply all of a sudden but I need to get this and a few other projects done before the summer really starts to kick in. Otherwise, they may not get done until the fall.

Enough whinging.:foottap: The flush trimming of the box required a larger bit than I had on hand so I bought a 1/2" shank, 1 1/2" flute, double bearing flush trim bit. That was just enough to handle the double thick MDF sides and front. I then filled any imperfections with bondo and sanded everything smooth. I installed the hurricane nuts and some 3/4" Sonic Barrier on the top, bottom and the back. Not sure if I'm going to need any stuffing inside there as well. Any thoughts?


























As mentioned earlier, I had thought I would try wrapping the veneer around some 3/4" round over’s but the box is simply too big for this to work with the veneer available to me. With the grains direction on the 4x8 sheets the way it is, I can't even go completely around two sides. So, a compromise is bevels. I now have much more freedom for selecting and cutting the pieces of veneer out of the sheet. Should be less waste too.

I used a guide with a circular saw to ensure nice straight bevels. A little sanding to clean up a few swirls from the blade and it was done.


























Hopefully I can get going on the veneer this week. I don’t think I’ll predict when the next update will be. I’m not very good at it.:scratch:


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## mwmkravchenko

A great application of using what you got to great effect.

Looking good!

Mark


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## ripcard

Thanks Mark, if I get this ready for the June 19th meeting/demo do you think it would be worth the effort of bringing it? (Anyone have a forklift I can borrow?) I just got confirmation that I'm clear that day. I have the DSpeaker Antimode 8033 as well, to play with.


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## mwmkravchenko

Worth it!

Absolutely. DIY at it's finest Rick. WIll be looking forward to listening to it on the 19th. I hope a bunch of guys show up and we get a whole boat load of stuff to listen to and look at.

Mark


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## bambino

Looks like a very nice build. great work Hope it sounds or pounds the way you want, from the looks of it you shouldn't have any rattleing issues. looks like i very solid box.


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## angelod307

nice looking for sure. i am curious though, i do not see any nails or screws holding this together for any kind of reinforcement. are you just using glue to keep it together?


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## ripcard

Sorry for the delayed response. I haven't been on here in a while. To answer your question...no nails or screws were used at all. The glue is more than strong enough for a cabinet that will just sit there. If you've ever had to take apart any pieces that were cured you'd know. The joint always breaks beside the glue joint. In the case of MDF or plywood the glue is stronger than the material you're glueing. Some will use nails or screws during construction along with the glue but it is usually for holding the joints tight with minimal clamping while the glue cures. Many will remove the screws and fill the holes before finishing. If I were building cabinets that were going to be moved around a lot and handled roughly like PA gear and such then screws would help but I think MDF would be a poor choice for that use.

On another note...I'm finally able to work on this again. It hasn't been abandoned. I just got too busy once summer arrived and had to put it aside. I'm just going through a few pics now and will post a progress report tomorrow.


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## ripcard

Back in the spring I was making pretty good progress on this project and I was hoping to have it ready for a local DIY meet in June, but I had an issue with the veneering process (my own fault) and then the summer got real busy. I was forced to put the project aside until this fall. Now I'm on track to complete it and bring it to our next local DIY meet in January.

Going back in the build thread you can see that I chose to make the cutouts for the driver, PRs and amp before applying the paper backed cherry veneer. I did this for two reasons. It would make the box glue-up easier and lighten it considerably for ease of handling. I did not anticipate having a problem applying the veneer, but that is exactly what happened. You can see that I tried the front and back first.

*Here are some shots of the Heat Lock glued applied for the first veneering attempt on the front and back.*


























Not shown is how I ended up with bad creases and wrinkles that could not be smoothed out. I'm sorry now that I did not take pics for the build thread. I had to rip the partially adhered veneer off and scrape all the Heat Lock glue off the two sides of the cabinet. This left a very rough surface which then had to be sanded, filled and sanded again. The two pieces of veneer could not be saved. Luckily I had just enough left to redo those two sides.

The problem was the moisture content in the glue wrinkling and warping the veneer. On a surface with no hole in the middle you simply start ironing from the centre, working your way towards all sides and it smooths right out. With the large cutouts and the size of the pieces of veneer, I could not apply them evenly starting from the outside. Lesson learned.

So, taking scraps from the build I made plugs the correct size and thickness to sit in the cutouts temporarily. They supported the centre of each sheet and the veneer went on with no issues. Then, using a sharp blade, I cut the veneer carefully, following the edge of the plugs. I sanded the edges flush with the original cutout. Quite a bit more work but it turned out fine.


*Once I had veneered the first side, the plug was a little thicker, so I shaved the back down a little using the router and circle jig so it would sit flush for side two. For the third side I actually had to slip some shims underneath because the driver cutout is deeper than the PR cutouts.*










*The room this sub will be placed in has a wood floor. I chose to make a more wood floor friendly set of feet rather than use the spikes provided in the CSS kit. They will have felt soles installed when the sub goes upstairs.*


















*I did not bother to veneer the bottom of the cabinet. Nobody's going to be lifting this thing up to see what's underneath. I sealed it with two coats of wood glue.*










*Ready for finishing*


























So, hopefully in the next week or so I'll have another report with the finish on the box and the components installed. Wish me luck.


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## mwmkravchenko

Maple?


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## ripcard

Ha Mark! Busted:sarcastic: Looking at the pictures only eh!:nono: First line of second paragraph: "applying the paper backed cherry veneer".:bigsmile:


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## mwmkravchenko

LOL


flash!


But here's a question. Can you make maple look like cherry?


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## ripcard

mwmkravchenko said:


> Can you make maple look like cherry?


A cabinet maker is asking a mechanic this?:unbelievable:


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## ripcard

*It is finally Done!* :clap::rubeyes::clap:


*After sanding to 220 the cabinet was finished with three coats of Watco Danish Oil Cherry and four coats of Minwax Clear Gloss Wipe-on Poly.*



















































*I wasn't entirely happy with the look. It seemed to be a little plain looking to me, so I decided to make up some trim out of black walnut.*




















*Here is the final finished version before it goes into the family room/home theater.*


























I finished it just in time to take it to a DIY meet we had in Ottawa last weekend. We were able to test it and listened to a variety of music. It is a solid 20 HZ performer with plenty of output. I will post the graph when I receive it from the fellow who did our testing. He had to do some travelling on business right after the meet. I haven't had a chance to weight it yet but it has to be closing on 200 lbs.

I'll give a bit more feedback after we've watched a few movies with it. It is replacing an older Definitive Technology Pro Sub 200. I will have the DSPeaker Anti-Mode 8033 Automatic Room-EQ to hook up between it and the processor.


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## Mike P.

Beautiful cabinet, well done!


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## bambino

Very nice looking sub, i like it's furniture like looks. I think that was a good choice in adding the trim.:T


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## ripcard

Mike P. said:


> Beautiful cabinet, well done!





bambino said:


> Very nice looking sub, i like it's furniture like looks. I think that was a good choice in adding the trim.:T


Thanks, guys. At 25+ inches on a side, I had to do the best I could for WAF.


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## GranteedEV

Love it.. although you must be sad that you won't be able to make a twin :hsd:


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## ripcard

Thanks. There is no way I could squeeze two of these in my room. If I decided to go with twin subs, I would choose a much smaller design. I considered doing my mains with built in subs but didn't have the space for the bigger boxes that design would require either.


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## mwmkravchenko

Lookin almost as good in the pictures as it did in person Rick.

Very impressive sub bothin build quality and finish.

Being on the measurement team at the DIY Ottawa weekend meet I can say that the sub measured very well. Actually you would be extremely hard pressed to find a commercial sub that could even approach the flat nature of the subwoofer's response. Within plus or minus 1.5 db from flat.

Very solid performer.

A project to be proud to be sure!

Mark


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## Steeve-O

Really nice build and really nice color. If only I could build something as nice. Great Job


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## ripcard

Appreciate the nice comments everyone, thank you. The disease has taken a serious hold now.:gulp: A Flexy stand in in the works, an Eton 8.2 build is in the planning stages and a ZRT is on the horizon. I have everything I need for the Eton build and about half of what I need for the ZRT. Is there any hope for me?:help:


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## ripcard

Here is an estimated near field response measurement of the sub taken at our recent Ottawa Winter DIY Meet.










I'm told by removing a little weight in the PRs I could gain some output between 25 and 30 HZ at the expense of a higher roll off. Easy to do since they are externally adjustable. Solid 20 HZ output as it is now. I'm not inclined to change it.


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## Mike P.

Do you have any EQ applied on the amp?


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## ripcard

When the measurement was taken in the hall, there was no EQ. I will have it hooked up at home with the Anti-Mode 8033 though.


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## ripcard

I know it's an old thread but my old picture hosting site went away and I had to use a new one. Fixed all the links to the pics. Seemed kind of pointless to have the text without the visuals.

Now I just have to fix the other threads in my sig.


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## mwmkravchenko

Good to see the pics are back up Rick!


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## BD55

ripcard said:


> I know it's an old thread but my old picture hosting site went away and I had to use a new one. Fixed all the links to the pics. Seemed kind of pointless to have the text without the visuals.
> 
> Now I just have to fix the other threads in my sig.


I'm glad you took the time to relink everything because this was a beautiful build, and I'm sure you are thoroughly enjoying it! It's definitely disappointing to find a cool looking thread and have all the pic links busted. 

Awesome build :T


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## ripcard

Thanks. The sub does sound great. Very clean, very low. Super happy with it. Works well as a side table beside the couch so the WAF is high.


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