tonygtr said:
Why is that? I mean, is there any particular reason stuff other than kick and bass will sound worse through the 15ma? There is a crossover freq. so after a certain point it would matter right? :?
The problem is around and below the crossover frequency.
Yes, there is a crossover frequency but in 2-way 15" systems it is always too high.
The 15" should be crossed over lower but the compression driver/horn is not able to go low enough.
While the frequency response
on-axis might seem okay for a lot of 15" speakers
off-axis they get very nasty in the mid frequencies that are very critical for voice, guitar and many other instruments.
12" seems to be the largest driver size that can still work reasonably well in a 2-way system. A 12" can go up to about 1200Hz and still perform quite well (1500Hz is pushing a 12" to the edge IMO) altough smaller drivers still have their advantages. A 15" needs to be crossed over considerably lower than that to give good performance.
If I remember correctly Jay Mitchell once mentioned that he doesn't like to use any 15" at frequencies over 200Hz.
He knows what he's talking about when it comes to speakers.
A 15" 3-way could of course be a solution but a 3-way of good quality will be more expensive, bigger and heavier.
A time aligned coaxial 3-way is really making things a lot more complicated.
S.R.