enclosure design help needed

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Hi,

At the mall today I had a good bargain for a pair of fullrange speakers that I couldnt resist.(some japanese 5' komachi brand).. and before I knew it I was carrying it to my car...😉

Now (the tough part) I want to design the enclosure for my little darlings without any specs available. All I know is that it has 4ohms impedance, 89dbm, 90-18kHz, 200W, which are virtually unuseful for me. Since I lack the basic tools to measure the T-S parameters of those speakers, I am wondering is there any box design that I can do without worrying about getting it &^%* up.

What I strongly have in mind is something small (ported/ sealed)to go with my SET. I heard that SET and fullrangers can do wonders, so I plan to build this as 'hi-fi' as possible. I do not require deep bass out of it.

Any ideas where can I start? Ive browsed over the internet but all I get is some formulas and response calculators..
 
OK, I'll hazard a suggestion: A Quarter Wave Tube.
I've had luck with these with unknown drivers. Just make it somewhat aesthetically pleasing. These "towers" have the advantage of putting the driver at a good listening height without adding stands. Plus they're simple to construct and you can make a prototype from cardboard. Also, their configuration automatically leaves space above the driver to add a tweeter, if you ever want to push the envelope. The bass can be surprising...
 
With no parameters and no measuring equipment it's going to be a complete guess. Assuming that most manufacturers exaggerate the frequency response of their drivers what you have may actually be closer to 100Hz to 15kHz. Chances are the best you can do is a small vented box around 3 or 4 liters. A 1" port 1" long I suppose. I Googled Komachi and all I found was a company in Singapore that makes home theater in a box systems.
 
I was suggesting a Tapered Quarter Wavelength Tube TQWT. Lots of simple designs and calculators/estimators around. I only suggested this as an alternative to a sealed box, which is the place to start. But with a TQWT, you get a few things for "free" (nice bass reinforcment, good driver height, slim tower look, spot for tweeter). The cardboard reference was not to Sonotube, but to flat cardboard from which to make a prototype. Surely you have already stuck these unknown drivers into a rudimentary baffle to see what they sound like?
It sounds like you have a pair of car speakers on your hands (4 Ohm, 200W[!]), but all is not lost. You could determine their Free Air Resonance, Fs, at least, with a multimeter and a test tone sweep. Knowing or estimating Fs (I guess 100-140Hz) will get you started on a TQWT. You will need more info about the drivers to successfully design a ported box, but with a supply of cardboard and an iterative process, you could get there, whichever type you chose.
And after you have practiced your wood working and soldering skills with this little project, you can decide if you want to continue with a project involving a driver of somewhat more familiar and documented pedigree.
 
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