3 way speaker system

[audioguru2]

Hi Xtp,
I have lost my speaker box program on the broken hard drive of my old pc.
I recall that your 1st enclosure is too big for an 8" speaker and your 2nd is too small.
I recall that your vents are too short for deep low bass.
Of course, the box volume and vent dimensions must match the spec's of your woofer.

You certainly don't need a 6th order crossover. I have seen and used many 3rd order crossovers and few have as many as 4th order.

 

[xtp]

My 1st enclosure sounded very well (only under 200Hz), but as I explained, it was too big (you said that too and I agree).
So how big should it be?
Should I use the 1st design (rectangular top and bottom) at a smaller scale (how small?) or the 2nd design (square top and bottom) at a larger scale (how large?)?
What should the volume of the enclosore be (approximately)?

You certainly don't need a 6th order crossover.

But it sounds great!
Will it work if I use three Linkwitz-Riley bandpass (highpass+lowpass) filters in series (highpass+lowpass+highpass+lowpass+highpass+lowpass)?

 

[audioguru2]

Hi Xtp,
The enclosure volume and vent diameter and length depends on the Thiel-Small spec's of the woofer. If the volume is too large then the speaker will "boom" at a single low frequency if the vent is also too large and the response will have a dip above the boom frequency. If the volume is too small you might be able to tune the vent so that the woofer has flat response only down to a fairly high frequency, but reduced response to low, deep bass. With small volume and a large vent, the lower response drops at a rate that can be boosted with an equalizer circuit.

A highpass or lowpass filter must be designed for the number of its orders in order to have flat response then a sharp cutoff. If you simply use three 2nd order filters in series then the response will be gradual and very droopy since the cutoff frequency will be down 9dB instead of only 3dB.