tweaking the Fostex 206E

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Slowly! I've put together most of the pieces, but haven't glued anything to the side wall yet. I've cut the driver hole and am about to chamfer the back side following planet10's advice.

I've also come to the realisation that by using mdf, each speaker is going to weigh around 100kg's!
 
Here's a progress shot:

An externally hosted image should be here but it was not working when we last tested it.


So far I have been very careful to caulk up all gaps in the speaker, and I am worried that when I attach the side panel there will be gaps that I would obviously be unable to seal up as I could not access them.

I figure the best way to reduce the chance of gaps is to make sure the surface is as flat as possible. At the moment it is not, because there are small differences in the height of some pieces attached to the side panel.

Is there a good woodworking method that I can use to ensure the surfaces of the attached pieces are perfectly level with each other before I attach the 2nd side panel?
 
you could use glue to fill gaps. Poliurathane glue, but I think is someway toxic, but I think there are other glue with good consistency. Put a lot of glue and when you put the side panel clean the excess.

The other solution is to level all with a tool. you must have a tool to see if it is all at the same level, it has water inside to see if it is all on the same level.

Other is to cut thin layer of wood and glue it to fill the gap.
 
I came across the same problem when I made my 208 cabs. In hindsight it would have been better to have put the back piece in last as there is only one piece attached to the back, whereas there are a lot of pieces to get aritight when you add the second side.

I glued and screwed both sides as I was puuting the outer skins on anyway so this hid the screws.

I infact ended up drilling a 4 inch hole in the back just above the rear shelf so that I could get a torch in to see whether the inside was all glued up. I then filled the hole with the plug that came out and filled it to make it airtight. The back slats made sure it was airtight.

I did in fact put some watered down PVA in to make doubly sure !

My carpenter friend has since put me on to "Gripfill" which looks exactly like decorators filler ( and smells the same) you can fill a 1/8th gap with it. When it dries it is as hard a concrete !
 
Consider yourself lucky mate - they say there's no such thing as a free lunch, but in DIY HiFi (of all things) there is!:happy1:


The 90° bends are a lot easier to build, that's one thing - but instead of punishing you for being one lazy bastid they help to attenuate unwanted midrange smut in the horn flare.

:cheers:
Pit
 
polyeurathane is the go.
Selleys Durabond.

Use about half what you think you'll need and clamp it.
then turn the box over quickly so if any runs out it doesn't go too far.

Dont wet the wood like they recommend. the bubbles in the foam get too big that way.

this is the result of a 2mm bead of the stuff on a humid day.
Don't you reackon that was fun to clean up. (1.2 metres to the bottom)

Keep the nozzle spotless, it expands on curing with enough force to split the plastic.

Oh yeah, My Drivers arrived today FE207E. and they are 183.2mm
your hole should be ok. they come with a nice gasket too. don;t use the screws they supply, those are terrible for MDF.
 

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Earlier in this thread there was talk of using calk to damp the basket.

Would blu-tac (poster sticking putty) be suitable?
I ask because it was on special in the shop so I picked up several packets just in case.

Should I apply it only around the basket and down the ribs or should I completely cover the magnet?
 
frugal-phile™
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OzMikeH said:
Would blu-tac (poster sticking putty) be suitable?

Should I apply it only around the basket and down the ribs or should I completely cover the magnet?

I've not used blu-tac but i understand it is suitable... keep in mind that it is as important to shape the rear of the speaker as to damp it. The most important part to damp is the basket/magnet interface. I wouldn't bother covering the magnet -- access to air helps in cooling the motor (althou i have been know to smother it in wool felt.

FE126-ductseal.jpg


dave
 
Thanks Dave.
I did something very similar to what you showed, but with the blu tac. I tied a piece of string around it just in case it gets warm and droopy.

I stole a couple of polyester pillows from the guest room and cut them up for the damping material, bolted the drivers into the unpainted cabinets and fired em up.
a work of warning: make sure you hide the carcasses from your wife, it's safer to lose something stupid than get sprung knife in hand slashing pillows up for your new speakers.. "But the shops just closed dear..." doesn't cut it.

The sounded a bit flat at first. Now I'm halfway though the CD and I'm about to turn them down for the third time.

I will pull them apart when I'm ready to paint I'll let you all know how the blu tac and string worked.

They are very directional, I'll be needing a set of those Phase plugs I think. Now where would I get them from Dave... :)
 
Tecnnically not a FE206E but I'm sure you can forgive me an FE207E
Apologies about the bad photo, the sun was at exactly the wrong angle and I was in a rush to try them out.

I went with the blu tac because I wanted something reversible, just in case there was something wrong with the driver.
Something more permanent will go in once I decide how to finish the cabinets.

Is epoxy (hard) or caulk (soft) better?

You say the shape is important too, I could build up the ribs into a wedge shape from the rear.

Another day of listening, they seem to keep getting better with the highs or I am getting used to them.
 

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It's my first post !

Hi all,

I am comtemplating the build of a full range speaker set and currently investigating what are the best options.
Fostex drivers seam to offer a good balance between value and performance.

It is interesting to see what people build with the FE206E. I like the simplicity of the Fostex recommended enclosures but I am still not sure if it is the best enclosure available.

Lately, my eyes are on the Decware site with their version of the 206E driver and the HDT . The DFR-8 is a tweaked version of the FE206E and looks interesting. Did anybody try the DFR-8 and the HDT enclosures ?

http://www.decware.com/newsite/mainmenu.htm
 

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The phase plug on the DFR8 looks very much like a 1/2 inch drive socket, as in what you use to turn a nut or bolt. Particularly when they mention the square hole in the middle.
Still: the price of the modified drivers from Decware is cheaper than buying two 1/2 inch sockets and two FE206E so go for it.

Mr Steve Deckert, if I'm wrong please correct me, I don't wish to mislead people by my quick, half baked assumptions.
 
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