FullRange driver and bafflestep?

[Twisted85]

Hi,

I'm new to full range drivers and I have few wonderings about the baffle step with a bigger cone. I've built few traditional 2-way reflexbox speakers and now I've been planning a somekind fullrange driver system maybe with a TL or horn enclosure.

It seems that people use fullrange drivers even without any crossover at all, doesn't this result in a very thin/sheer sound as there is no baffle step compensation at all?

I'm very interested of using this driver:

TB W5-1611

To me it looks like a fine choice for a TL system.

Instead of using a baffle step attenuation I've been thinking a choice of adding another driver with a 1st order lowpass near the bafflestep. I'm not worried of the lower frequencys coming from two different sources (If I've understood correctly this if just fine with TL), but the lowpass would cause a 90degree phase difference.

I'm still just planning this project, I don't want to order drivers before I really have all things clear and ready.

 

[Jim Griffin]

Your suggestion is what is called a 1.5 way configuration wherein the full range driver covers the entire frequency range and a second driver addresses the baffle step effect so it covers only a portion of the frequency range or the '0.5' part. Normally, the transition is low enough in frequency that the 90 degree phasing difference isn't audible.

Essentially, your TL would have to be sized to support the second driver (doubles the box) and an inductor would be used to roll off the second driver appropriately to cover the baffle step region.

Another way to do this with a second driver is to use a bipolar configuration--one driver fire forward while the second driver fires rearward (bipolar means the drivers are in-phase) so that acoustical in-room SPL 'self adjusts' for the baffle step effect. Again the TL is double sized but no LP filter (inductor) is necessary as you have addressed the acoustical effect without the need for a filter.

Jim

 

[norman bates]

I'm using dual 4" driver (with 5" frames touching) in a 8" wide sealed box.

I simply use the "loudness button".

The mids and highs (with a dual driver setup) are much cleaner than running a 1.5 system for me (or covering bottom woofer with 3" of foam).

But the listening angle (vertically) is critical.
Think 4" vert sweet spot at 12'

I don't think your 5" driver with a larger frame would be able to pull the trick off quite as well...............

Norman

 

[Twisted85]

I guess I'm gonna order a pair of the TangBangs and see if I like them. I thought I could try how would it work in an open baffle too, although I don't have too high hopes for a good power response.

 

[norman bates]

my favorite setup was a w3-871s on a wide open baffle.

All was excellent, untill any bass shows up.................

I may someday remake it.
Sometimes our old projects were good for us at the time but when revisited we see the flaws that we were blind to before.


Norman

 

[hm]

Hello,

thanks JIM,
"Essentially, your TL would have to be sized to support the second driver (doubles the box) and an inductor would be used to roll off the second driver appropriately to cover the baffle step region.

Another way to do this with a second driver is to use a bipolar configuration--one driver fire forward while the second driver fires rearward (bipolar means the drivers are in-phase) so that acoustical in-room SPL 'self adjusts' for the baffle step effect. Again the TL is double sized but no LP filter (inductor) is necessary as you have addressed the acoustical effect without the need for a filter."

one important fakt i miss,
best result you get with two different horns,

a bipolar double horn, with a invers bassmid driver would be a
superb solution.