fostex 206E back loaded horn failure

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I just read this thread. Sorry you don't like your current speakers. I was thinking along the lines of Norman and Marce as i read but you tried and still didnt like. Scott had the best suggestion to swap your drivers with your friends and see if they sound different. I've gotten fostex drivers from madisound and the same models have even looked different... wizzer cones at different heights and different cone color. I remember sending back my fostex 168s and asking them to open up a few from stock and match a pair physically... and they did!

>>> I am still open to more suggestions what to build next.

I always like to recommend BIBs because every time someone builds a pair they love them. Sometimes people tell me they've built a pair in one day! Took me a few weeks! Mine have plywood sides, particle board inner baffle (which i would like to have done in ply) and a particle board/pine front and back. This way i don't worry about which wood to use, i used them all. LOL. I built the fostex bk161 out of mdf and it did not like it.

http://www.zillaspeak.com/bib-pics.asp

BIB pics at above link.

Godzilla

PS, i did a search on my pc for dallas to see if by chance i saved the file years back... the only thing that came up was the Debbie does Dallas poster.
 
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gerado said:
Scott are you confirming that the dallas 2 plans on Rons site are not detailed for a build?

Plans are detailed enuff to build from, but you are working from what could be gathered as pdfs or jpgs (plans should never have to go thru the insult of being jpgs) after Windows ate the original plans.

Freshly redrawn plans of A166 are nearing completion (thanks Chad) and a good start exists on A126, but Dallas is still in its current limbo.

dave
 
Scottmoose said:
Ron's DallasII is probably the most advanced compact back-horn around, but it's not an easy build, and following an HDD crash a couple of years back, the plans have had to be reconstructed somewhat. I believe Dave is planning on re-drawing them, but it's a case of not enough hours in the day.


I found these Dallas II plans in my HD archives. I don't know if they 're more detailed than others maybe have. Please also confirm that they 're the right ones.
Regards,
George
 

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aroS3,
thanks for the plans

these are identical to the ones on Rons site
I think I thought of a way to get around my concerns about getting the angles right.
Drawing the plans on one of the side panels should be more accurate than relying on the cut angles to align the wood up.
 
What about drawing the plan on the wood you are using, the old fashioned way? If you wanted to you could measure the angles at that stage and even create templates.

Thats how I did my Hedlunds, drew it out on the wood, yes it takes more effort and more time but think of it as therapy, plus, the chance of errors are minimized as every piece is cut to fit the actual enclosure you are building.
 
OK ,

did a few things suggested here. Moved the horns inside , moved them about various positions to no avail. Even borrowed a spare pair of the 206 drivers just to be sure as Scott alluded to that I did not have a dud pair but nothing doing.
All they do is shout at me and have a low end that is confused and hopelessly thin and echoes. It sounds better with a couple of pillows stuffed down the mouth of the horn.


So I took a rubber mullet and went to work! I got one side piece off, the glue did not give way but the wood did. I am now convinced there were no air leaks and the build has no errors.
To my ear the fostex 208sigma enclosure for the 206e driver is an absolute dud and I am moving on.

I have 2 options before I start building again. I can install my drivers into Jericko enclosures for an audition and I will hear a friends sachiko horns which are virtually finished.
I do like the look of the Dallas2 and more so the Mauhorn IV however.

I will post my thoughts soon again.
 
You findings that the 206/206 combo don't do bass is very surprising. It's not what most people find (me included)

I use mine to good effect in a smallish room.

I have a largish lounge 17feet by 20ft approx. I have tried the horns in there and many other speakers in many different positions. I cannot get any decent bass response. It is not the speakers but the room.

Have you tried other speakers with success in your room?
 
My room is not ideal but get plenty of base with other speakers I have. I am really perplexed considering everyone else experience with the combo.

Puffin you mean 208/206 or 206/206?

As a point of reference for me, are you getting as big a sound as say a high quality floorstading multiway speaker standing say 4and a half to five feet high? I am not referring to the quality of the base here, which I expect the horns should excel, but the quantity. Are you getting as FULL a base as a box speaker?

brsanko, isnt hornresp for front loaded horns or have I made the incorrect assumption and it is suitable for BLH?
 
Scott,
please do not misunderstand me,
I was not suggesting that FR should sound LIKE multiways, I was trying to get a sort of reference point for myself as to the QUANTITY of base volume. I want to work out what I am doing wrong or if I am expecting far too much in the lower registers. It is difficult to know what people are hearing when they say they have plenty of base unless there is some sort of reference point to judge by.
With the 208 enclosure it is now irrelevant as I have broken them down.

I will choose something else and hopefully be listening again in a few weeks.
 
I get very good bass from my FE206E's in the FE208EZ cabinet, not earthshaking but deep enough to be enjoyable.

See here: http://www.youtube.com/watch?v=z16Gcr5tDvw

They did however sound very thin initially, and it took a lot of burning in with bass heavy music before the bass started to develop. I also found that using minimal dampening helped - I have thin (2 - 3mm) linings of felt in the places recommended in the fostex design.

Some possibilities for your lack of bass that I can think of are:

- The drivers might not have been burned in with music that gets the cones pumping enough; or
- Build error. Even getting one internal piece a fraction of a mm off could be enough to cause a leak, and I found this very difficult to avoid when building mine. To combat this, once I had attached all internal pieces to the side panel I then painstakingly constructed a rig around the box that allowed me to slide a router over the side (kind of like a cnc machine), shaving off just enough wood to make sure that a level surface would be created for attaching the final side panel.
 
:D

...and the sentence of the Court upon you is that you be taken from this place to a lawful prison, and from thence to a place of execution. And that there, on a date determined by the Court, you be hanged by the neck until you are dead. And may the Lord have mercy upon your soul.

Ahem. Back on planet Earth, nice writeup I thought. :)

My gut feeling is still that something went wrong with the build (the dreaded MDF won't have helped matters), as the reported result contradicts considerable positive past experience. Either that, or, if the LF gain is expected to be similar to a 5ft tall multiway (albeit unspecified), then methinks the man doth expect too much from a relatively compact box.
 
Hi Scott,
Do you have simulations of these Fostex boxes?
In my room there is a dip around ~65-90 Hz. Now the bib's and the Sonido horn I have made, have also dips around the room dip. It makes them sound pretty heavy and have strange phase shifts in the bass when moving around. Hollow is a good description and without impact to drums to them.

The others, bass reflex and sealed I have had in this room had not so much of this problem.
Dunno know if this could be the problem....

Peter
 
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