X1 Highpass Filter

This will indeed get us bandpass characteristics. Of course higher freqs will 'escape' because the 'hole' is directly in front of the speaker... but I guess the low mids (100-250Hz) won't be good....

It's not only beaming I was talking about. It's more the fact that the mids, even if the freq plot is smooth, won't be that detailed. I have some really smooth sounding 15/2 type cabs, but it isn't comparable to 10" and smaller mids.....

Of course, if you build already existing designs, they will perform like intended.

In my case most existing deisgns won't fit my needs.....

I think the HF driver has a highpass at 2kHz, but the 15" somewhere around 1100 or 1200Hz or such. This is because the HF driver has a big hump around 2kHz and below and the acoustic crossover frequency is much lower than 2kHz.

I don't think that a 15" speaker should go higher than 1200Hz. Even that is in many cases too much if you want clear mids. It's plain physics. A cone with voice coil has a certain weight. This weight will act like any accelerated mass. The bigger the cone and the VC, the higher the mass. And the higher the frequency, the higher the acceleration. So high frequencies AND big cone add up to 'not that good at all'.

It is NOT about 'mids are weak in SPL' or 'the freq plot isn't flat', it's more a question of details in sound.

It would be a good idea to consider 'filtering options' BEFORE you get your hands dirty.... Just think about the speakers you're going to use. If it's a 15" and a small 1" HF you know for example that you need to crossover the 1" very high (2kHz and above) and that the 15" won't play good that high.... so you know this wouldn't be a good box.

Or you want to build a 15" 3way cab. So you get an 8" for the midrange, now you have to check what's the lowest frequency the 8" can play well.

I don't mean that you should have the crossover ready before the speaker. I just think that you should know what you want first....

Dom wrote: And if it takes you longer than 30 days to measure your delays then you've got problems...

Or a really bad BP6 or higher.... :)