Car Audio Fundamentals, Myths, Misnomers, & General B.S. - 2007 CA&E

[Euphonic]

Kelly, Tim "Car Audio Fundamentals, Myths, Misnomers, & General B.S." Car Audio & Electronics April 2007: 62-64.

[Captain Buff]

I have always wondered: if indeed the best place for the tweeters is as close as possible to the mid range; why not just use coaxials? Can’t get the tweeter much closer than that. Or if wanting separate active drivers then a brand that allows you to attach the tweeter to a ‘middle mounting pole’ of the mid range (I don’t know if these are still around...I had some back in the day)...
Any thoughts as to why what I just said is rubbish...?

[Sudoku]

I think that used to be a popular method, looking back through some of the classic builds shows tweeters attached over the mid, often using rods or brackets, and usually in the kick panels.

Kef (UniQ?) were also used, I believe this is a coaxial of high quality, and has separate inputs from an external xover, rather than the simple cap hi-pass used on most coax.

[diy.phil]

The coaxial speaker will be nice for time alignment and imaging. But one issue is sound in a midrange speaker originates from the voice coil's circle/area and not the outside cone/paper/surround area. We can verify this by holding a tube closely to the center/voice-coil and the other end on our ear (empty kitchen towel tube will work). If we put a large tweeter on a post/pole in the middle ("coaxial speaker arrangement") it will kind of block or color the sound from the midrange... so, some separate/component speakers are more desirable.

[Captain Buff]

The coaxial speaker will be nice for time alignment and imaging. But one issue is sound in a midrange speaker originates from the voice coil's circle/area and not the outside cone/paper/surround area. We can verify this by holding a tube closely to the center/voice-coil and the other end on our ear (empty kitchen towel tube will work). If we put a large tweeter on a post/pole in the middle ("coaxial speaker arrangement") it will kind of block or color the sound from the midrange... so, some separate/component speakers are more desirable.

Yeah makes perfect sense mate, cheers for that ��

[Euphonic]

I guess it depends on the coaxial. There’s a handful of home audio companies that thrive using them and people seem to be quite pleased with the results. The automotive environment is different though, so maybe the extended range drivers offered by some are the better way to go.

[ckirocz28]

I have always wondered: if indeed the best place for the tweeters is as close as possible to the mid range; why not just use coaxials? Can’t get the tweeter much closer than that. Or if wanting separate active drivers then a brand that allows you to attach the tweeter to a ‘middle mounting pole’ of the mid range (I don’t know if these are still around...I had some back in the day)...
Any thoughts as to why what I just said is rubbish...?

Aside from the aforementioned issues, with a larger or lower frequency woofer, inter-modulation distortion becomes an issue, heavy bass "pumps" the frequencies coming from the tweeters.