One of the user pics seems to show a home built ZOB with felt lining the inside of the entire resonance chamber!?!  Is this as wrong as I think it is? If no felt is used on the inside of the chamber do you paint it or seal it? Polyurethane?

The spikes... attached 'hard' or with felt? My instinct is they should be 'hard' attached

No mention is made in the plans of how you attach the boards to each other. Glue... screws.. brackets? Screws into the end grain of any processed wood is usually not a good solution.

Probably think of three more ?'s as soon as I post this

Thanks

Before I start this project, there are a few questions that I have concerning the cabinet(box). The first would be about the material used for the box( not the baffle). Does it matter as much as in other speakers what material is used? This enclosure is not a pressurized design, and I wonder if the material used affects the sound as in other speakers. I thought that I might use plywood or MEDEX(a type of mdf product but denser). Also, would the thickness of the material be as important? I'm not suggesting a cardboard box , but want to know the limitations of the materials needed.
 Still, I have not seen an answer to the question about lining the box with felt. I see that stuffing has been mentioned, but how much?

Thx in advance for your time.   Greg

I agree with ZYGI on the MEDEX. MEDEX is an acronym for exterior mdf as it is water proof (resistant actually) and not as prone to the expansion the lower grades are.
Living in Hawaii, I can use neither and used marine ply with 13 laminations for my HDT build. Worked well.

Nowhere is city proper for me. The nearest Home Depot is 98 miles away. And MEDEX, well they just gave me a strange look when I proposed to order some. They did have 9 ply available, but I don't know how that ranks with the other options. I wonder if HDF is good enough.....

Your ahead of me. I am just cutting out the baffles today. I am using 1 3/4" cherry. The rest of the build is still forming in my mind. Will probably use a 9 ply  plywood if I can get the quality that is needed. I figure that material can be added to dampen the enclosure if it is too woody or boxy sounding.

There really is nothing like the beauty of wood. Thanks for sharing the photos. It makes my mouth water.....As I recall, I spent about $80-90 per piece for the lumber. Unfortunately, the shipping was nearly as much! I just got done planing the boards tonight. Cherry is so much more attractive to me after a few years of darkening. I will try to take a picture of them tomm, but I always fail to be able to get pics onto this website, cuz it says that the files are too large. Then when I reduce them, it doesn't like something else about it. I don't remember what anymore. But I could e'mail them to you or something....

Good to know  'D'.  I wouldn't bet on it, but I either have a 3 1/4 hole saw, or a circle jig for my router that will accomidate.  Now ya have me wondering.....    Btw, I checked out the prices for 17 ply and the 'perfect plank' wood, and even though I think that the prices are fair, they are out of my range.  The ply was $110, and the other was $152, and that still probably wasn't enough board feet...dang! I will have to take a trip to Montana to find anything better than what is available here in Wyo.

Thanks  and that is something I could have used. I do have an Ace Hardware and did go there.. when I asked for a hole saw and they didn't have the one I needed they didn't suggest this which makes me wonder if they had it. Very small Ace hardware... kind of an afterthought added on to (and completely supported by) the Farm Bureau CO-OP.

Anyway I have already ordered and received the one from Amazon, I cut my holes yesterday.

Now I just need a new Table Saw.... Oh Yeah did I mention I burnt up my table saw on this project? LOL. Yes I did but there is a story about the saw.  It belonged to my dad who kept it in his basement shop. When he passed away I got all the tools but before that there was a flood and the table saw and some other tools got submerged. The Table saw was never the same since. It still worked (very loudly) for light work but 2 sheets of 3/4 board isn't very light. Also it's no great loss because even when it was new (about 30 years ago) it was a very cheap one.  

About the spikes

Are the dimensions on the spikes important. I am assuming they aren't since no mention is made about their size in the ZOB plans. Tall enough to keep the box off the carpet so it can resonate? Pointy so the spikes themselves dampen as little as possible?

Dad's shop was mostly metal working tools and the lathe works just fine. I have a piece of stainless steel stock about 2" or so diameter that I plan to turn these out of

Well I spent the last several hours turning some spikes on my lathe. All went well and I now have 6 stainless steel spikes ready to go. Either glue or drill and tap the spike with a bolt through the bottom. I have some VERY good glue that I think will do the job. I plan to make the bottom removable until long after they are done, only adding the glue to it after I am happy with the final product. With no dimensions to go with I used what I believe the Navy refers to as 'Mark I Eyeball'   Yeah I chose an angle by eye, didn't look right so I went a bit tighter. Turns out a 55˚ taper makes a good looking spike. I didn't make them sharp enough to warrant a visit from Homeland security, but if you set one on your foot you are NOT gonna be happy. Left a 1/8" flat on the bottom


I did make a design change I want to mention. I dislike the idea of the screws/glue/joinery around the bottom holding all the weight of the cabinet. So I modified the measurements so I could make the entire cabinet set on the bottom piece. This will give a visible joint but I am ok with that. I was very careful to preserve the exact dimensions of the resonance chamber and associated baffles etc.

I guess this weekend it's a trip to Indianapolis to the lumber company that carries exotics. I also have to shop for a table saw..

Sadly... I don't make the kind of $ to spend 1000$ on an occasional use item. However I did find a decent 10" Craftsman, used that had broken plastic around the base. I fixed that with some L angle iron and some strap. MUCH more saw than I could have afforded and it does indeed have a decent fence. I think it cuts up to 24" wide. 40$ Also picked up a Craftsman 16" Scroll Saw in mint condition 40$.

I have my eye on a planer and a jointer. Just trying to decide if I truly plan to get into more woodworking or if this is a passing phase/midlife crisis If I get them that means no iPad for me... decisions decisions..

To further complicate matters my shop is also my garage and it's pretty packed already so smallish and portable are a plus where possible. I  have several non portable items I have to design my floor plan around...

Just an update; I chose 11 ply baltic birch for the side panels and some other parts. I am using solid rosewood for the top of the box and the back, and I am using solid cherry for the baffle. I will be using a combination of glues , brackets, and pocket holes to assemble this beast. Surely, it will weigh more than I first expected, but I like that idea anyway. Now, I have to decide if I am going to stain the side pieces to match the baffle or the rosewood....

Damien,
  Hows the project coming along? Looks like we have plenty of time to complete them before more FRX drivers will be available. My project is still in the rough cutting stages, but I'm not worried since the weather is finally good enough to let me work in the shop. Sooner or later, I will get far enough along to take some meaningful pictures....

Man,  you have been busy! I will swallow my guilt and get back to work. What glue are you using? I plan on using 100% silicone caulk and brackets, but mine will be on the inside.  Thats some really cool maple that you have for the baffles. How thick is the veneer for the walnut sides? Or did you say you were going to paint the cabinet black? I'll try to take some fotos of the baffles tonight.....later

'D',  Something I just made this weekend may be of interest to you. On my ZOB cabinets, the cones were mounted close to the edges, but there was still some wobble due to the width of the cabinet. So far, I have built outriggers for the front to stabilize the cabinet from rocking(about 3" sticking out on each side), and it works really well. Also I think that the profile of the cones need to be slimmer so that they can stick through carpets easier and get to the floor. That may be the next trick.

OK,,,GEEEZ  I only have the front ones done so far. http://s1117.photobucket.com/albums/k585/4krow/?action=view&current=PA180001.jpg... steel.http://s1117.photobucket.com/albums/k585/4krow/?action=view&current=PA180005.jpg...

'D'   they replace the original spikes. In fact, the outriggers use the same t-nuts that the spikes used. I will probably install one outrigger for the rear as well. I might even go as far as to weld the rear outrigger to the front one, forming T shape that extends to the rear, making a one piece outrigger for the front and rear of the speaker.

I put three spikes and got the job done. No wobble. Rather than doing mods, maybe a "sharper spike" that goes through the carpet  could be a solution.
With four spikes, you always have the problem of getting them to stabilize....  due to vibrations etc , you will find that you will need to tighten them occasionally. With  three, you don't have that problem.

Stick to the original plans....... I have done it without any problems.

shreekant

Ok, it's me again. This is about protecting the FRX2 from stupid people poking around/standing too close to/ leaning on/raising my blood pressure. Fortunately, I don't have a lot company, but the few that do come over raise my blood pressure by simply being way too close to the fragile drivers in my speakers. I have considered needles/razor blades/vicious dogs to try and keep their curiosity at a safer distance. Maybe grills that can be taken off when listening would ease my unease.  Any ideas?

hey....I thought rats were sacred....besides they totally mess up the sound stage.

Is there any alternative to the FRX2? Sounds like it will be some time (years?) before I get to the top of the list.

Is it worth the wait?