adding a woofer driver to a full ranger

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Ok, here what I asking about,

say you go full range with a single driver (like Fostex or something), no x-over.

then you add an inductor in series (1st order low pass) to a woofer driver to add some content below say 150Hz.

Anybody do this with satisfactory results? Can you share some examples.

Thanks
Paba
 
I'm currently running exactly that. I have a FE206E running full range with a 10" Realistic woofer on each side on open baffle. I wound a coil with what I thought would be an extra 20 turns or so and removed windings until I got to a seamless integration. With only a 2 watt amp, I don't have to worry about over excursion of the 206. If I ran more power, I would have to address excursion on the 206.

To do it you need a woofer that sounds good well above where you plan to cut it off. Also with OB I think it's a little easier than in a box because the natural rolloff of the full ranger above its Fs is shallow and easier to match with the 1st order rolloff of the woofer, plus you can adjust the baffle too to change the character of the full ranger's roll off.
 
Thanks for sharing, sounds very interesting and do-able.
I like the Fe206E as well, it is 96db, is your RS woofer also in the high 90s, or does it matter? I had not considered OB for the woofer, but why not. Sounds like I will have to do lots of experimenting.

I have about 7 watts per channel to play with.

If you have a photo you can post just to get a visual of the setup. If the woofer is below, does that force the fullranger to be too high off the ground? I'm assuming your Fe206e is in a back loaded horn, and then you raised the horn cabinet to insert the woofer.

cheers
paba
 
They are both OB and mounted on a 17"w X 30"h piece of plywood. I use them nearfield at my desk (1m), so I can get away with the narrow baffle. My amp likes low impedances, and the 4ohm load in the bass region is no problem. I think the woofer is only about 89-90db but there's bass coming from the 206 as well, just not a lot. Due to my close proximatey to the rear wall, I have a layer of polyfill batting draped over the back of the 206's to tame the highs.

My speakers are tuned only to my setup. A nice thing about OB, is that tweaking is easy. I got very lucky that the pair of woofers of unknown specs worked so well and I think my desk combined with the wall boundary resulted in much more bass than I anticipated. I ended up turning my sub off.

With OB, listening distance, baffle size and shape, placement, room boundaries, woofer specifications and mounting height are all part of the equation when it comes to bass. The easy and most typical answer if you aren't using EQ is to use big baffles, but I think they are hideous and that means more tinkering.

If you are using a rear horn and need help on the bottom end, I think a sub would be more practical because you'll need a physical separation from the horns to address the phase issue and you'll need the separate adjustability of a sub to make integration easier.

For a more typical listening setup to go totally OB with the 206 and get good bass, you'd probably need 2 woofers to get really good results without EQ. Although a highish Q pro type 15" with good efficiency and low Fs in a compact U baffle and the 206 on top with a small baffle might work very well.
 
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did it with an 8 inch

Had some Visaton FRS8 bipoles. I combined an 8 inch cobex cone English woofer from an old kit, custom made (probably by Celestion) for HFNRR's Dave Berriman.
I used 35litres closed box for the woofers.
The trick I used was to wire the bipoles into dipoles. So they developed a naturally falling response towards midbass due to front to back destructive interference. I enhanced it with a cap and used a coil for the 8 inch.
The system got significant body and spl as a whole.
Integration was great but still you had to listen at a 3 metres distance to start forgetting the 2 separate sound sources. A multiway speaker listener would find it seamless but we into fullrange, know better.
 
I'm running something along the same lines... Except the fullrange driver has a capacitor on it as well. I've got a fostex 108e sigma in a small sealed enclosure with a first order cross over at 600Hz to a Emeninence Delta 12lf in an MLTL. I tried the 108 with out the cross over but in a sealed enclosure it exceeds its x-max quite easily. I did not notice any real degradation in the sound from the capacitor on my fostex... though I'm not claiming any golden ears or anything. I'm quite pleased with this set up. Much more body, and more dynamic than anything I was able to get with the 108 by itself.
Joe
 
Until we have the room to make Nelson's big horns we have to concede that there is no such thing as a full range driver and get our bottom end filled by whatever means necessary.

If Salas can really hear 2 separate point sources at 150hz or so, I'm glad I don't have his ears. I think is was the bipole/dipole blending with a sealed woofer that resulted in 2 audible sources.
 
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overtones

It is not the 150Hz but the overtones reproduced by the woofer, especially without a steep crossover slope.
But 6dB was the best integration (nearly but not 'exactly' seamless).
Steep filters I tried also but the result was audibly more mechanical considering musicality and rhythm.
Yes omni to bi transition must be a thing that was picked up too.
The result though was excellent by many standards. The -3dB 40Hz bass and the power handling increase transformed the system to a greatly satisfying music machine.
 
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