Fostex FP203 suitable for a sealed box?


I´m a newbee on this Forum and this is my first thread som please bare with me in case you find my question stupid;)

I have had two old Fostex FP203 lying around for like 10 years and now I need two fullrange speakers so I´m thinking about if the could be useful or not

The project I´m thinking about is to build two fullrange speakers for my bedroom LCD TV (37") . It´s not a surround project, just want to get a bit better stereo quality sound from the TV.

I was thinking about builing a sealed box and frankly the dimensions are more important than the sound quality (as long as the sound will be better than my original TV speakers that is..)

So my question is if the FP 203 is suitable for a sealed box construction or if I should choose another type of speaker for this project.

I realise that this could be a very complex question to answer, so I would appreciate any links you might have that could be useful for my further investigations and planning

thanks :)
Petter Persson said:
Sorry, but i think it's not...

Too low qts for that, a bass reflex if you would have to build a
really compact one. Othewise i would recomend my project

if that is too big, some sort of TL or pipe, about 1.5-2 meter
long...what dou you have for limitations in size? I think BR sound
so boooring...

Ha de gott / Petter

Thanks Petter!

well your project looks very interesting but for my usage as speaker solely intended for my TV it might be a bit to large (for my wifes taste that is ;) )

Last loudspeaker boxes I built was was like 30 years ago, "RT-70/80 horn" but I remember my intentions when I bought these Fostex drivers, that I was aiming for som kind of pipe or transmission line project. Unforytunately I have no clue what I should search for regarding drawings etc, so any help would be apreciated

Do you have any suggestions on other projects? Like a 1/4-pipe, Voight or similar?

Have a Happy New Year!
Hi...measured data from a friend in Sweden:

Fostex FP203

Fs 47,2261 Hz
Mmd 9,096 gram
Mms 10,722 gram
Cms 1,0592 mm/N
Rms 0,3132 kg/s
Vas 60,2 liter
Xmax 2mm
Sd 210 cm^2
Re 7,7 ohm
Le 0,155 mH
Bl 8,2979
Qms 10,1584
Qes 0,3558
Qts 0,3438
no 1,7273%
SPL 94,54 dB-2,83V/1m

good luck:)
Hmm. In between latest formats & reinstalls of my PC at the moment (now on the 7th since New Year's day) so apologies if I'm only sporadically around for a while. Dead-easy solution though: using the above figures, and assuming that a horn of the more conventional sort is out for space considerations, I'd be inclined to do a nice & simple MLTL. Like this one (internal dimensions given)

54in x 9.25in x 12in (HxWxD).
Zdriver (distance of driver-centre from sealed end) = 19.875in
ZPort (distance of port-centre from sealed end) = 52in
Vent = 3in diameter x 1in long
Line the cabinet with 1in acoustic fiberglass on opposite faces (suggest top, back & one side-wall) or stuff 0.25lbs ft^3 from the top 30in down. I'd suggest 3 window-braces & a front-back brace that also clamps the rear of the driver securely to the rear panel. Birch ply prefered for the build material.


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