Dd67000 crossover points?


The midrange driver covers 850 to 20,000 CPS. Thoughts on a single drivers covering such a wide bandwidth? Do any others speakers do this? Pros & cons?

ptss
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The JBL 4367 is a passive two-way (15" woofer and 1.4" throat horn) with a crossover at 700 Hz.

Imo it’s a good idea to cover the range from about 1 kHz on up with a single driver, and crossing over a bit lower than that would be even better as long as there are no unacceptable consequences, such as significantly reduced pattern control and/or power handing.

I’ve covered the region from about 750 Hz on up with a single compression driver in custom studio monitors, but have not yet done so in anything that I have in production.

Duke

Without taking anything from the Everest, I would really want confirmation about the super tweeter coming in at 20 kHz. That seems supremely wasteful.

Otherwise, this is almost what the DIY community calls a Woofer-Assisted Wide Band (WAWB) which has quite a following. The idea is to use a wide-band driver and/or horn to keep any crossover issues out of the human voice range, but adding a woofer to cover the lowest octaves. It’s a neat idea with many positives and also a lot of negatives but definitely an approach worth considering. I think of a WAWB as a variation on the full-range, single driver designs and a way of overcoming the limitations in bass output in a tidier manner than folded bass horns.

The DD67000 seems to take this to the extreme by adding a second woofer and a super tweeter, but I’d consider it more or less in the same faimly. Check out all the articles over at DIYaudio on the pros and cons of a WAWB.

Also worth noting, this is an ideal speaker for Sanders amps.  The impedance is worse in the high frequencies than in the bass, a situation which is the opposite of what most normal amps are expecting, which have higher damping factor below than above.  Do you need it to play from 20kHz to 40 kHz though??? That's another story.

Interesting also that the crossovers are 24 db/octave.  This helps reduce power to the drivers but also offers excellent vertical response.   That is, you can sit or stand up and still hear an excellent frequency response without destructive interference in the crossover regions.

An approach rarely seen in passive crossovers.  This shows they are leaving nothing to disturb the carefully chosen horn designs.

Analysis Audio Planar Ribbon speakers use a first order crossover at 600 Hz.

Arion Audio Apollo speakers use fourth order filters at 120 Hz.

If the drivers and system are designed for it and the drivers have the headroom it can work very well. There are very many things that have to be taken into account. For example our Arion AMT drivers are mechanically damped so they are able to follow complex wave forms which is exacerbated by the extended range they must reproduce.

I have enjoyed DD67000s on many occasions. A wonderful speaker by many accounts. I'm sure the engineers at JBL did their homework and met their design objectives.