Can anyone tell me if this is good?

[wxn]

I have recently spotted a neat thread about 3 FRS8's in open baffle and a Visaton W170S as a woofer iirc.
Now, I've adapted the idea a bit to my taste, I'd do three FRS8'a in parallel with some resistance in series (I surely don't want to load my amp with 2.6ohm) or four of them in series/parallel in a small closed box. This would give around 87-89dB/W/m.
And for the lows, I'd choose WS20, which has neat frequency responce in a closed 40l box, has 87dB sensitivity and its cone is made of polypropylene (which is said to be a good thing for rock-type music).
Crossed at about 400Hz with an active 2nd/4th order Linkwitz-Riley crossover. Everything would be driver by a dual LM3886 amp per channel.
Well, what do you think about it?

http://www.visaton.de/english/artikel/art_486_1_19.html
http://www.visaton.de/english/artikel/art_486_1_19.html

[kelticwizard]

Originally posted by wxn
[B....or four of them in series/parallel in a small closed box. This would give around 87-89dB/W/m.

Well, what do you think about it?

http://www.visaton.de/english/artikel/art_486_1_19.html
http://www.visaton.de/english/artikel/art_486_1_19.html [/B]

One FRS-80 has a sensitivity of 82 dB21M/1W.
http://www.visaton.de/english/artikel/art_261_1_3.html

Four of them in series/parallel hookup will give you about 6 dB higher, (88 db) IF they are hooked up in the following configuration:

00
00


However, if they are hooked up in a line, like below, they will not get their sensitivity raised 6 dB. It might be raised 2 dB or so. This should bring you up to a sensitivity of 84 or 85 db:
0
0
0
0

[wxn]

Even if so, this doesn't change much. I'll just have to adjust levels a bit...

[kelticwizard]

You might want to ask the open baffle experts about that 400 Hz crossover. From what little I know, the open baffle rolloff begins at half a wavelength. Half a wavelength of 400 Hz is 16 inches.

So it looks like you might have to either do some equalization for the open baffle at the low end, build the baffle much wider than the woofer you're using, or maybe wrap around the baffle to make it resemble an open back type design.

People more experienced with open baffle design can maybe give you better advice on this.

[wxn]

in a small closed box.

in a closed 40l box

Sorry if I didn't emphasize that enough.