Omnidirectional designs?

I saw these old cabinets posted in a discussion group on Facebook, apparently originally these used an upward firing 12” fullrange speaker.
Curious if anyone tried to diy similar designs? Do they work well?

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I have seen that design somewhere before but can't remember the page. What reminds me is the fact it looks like a trash can.Looks cool to me.i have a special interest in omni's.

I think that the driver requires a rising top end (quite a few FR's do) and the shape of the diffuser / reflector is very important. That one uses a cone which are said to be better than spheres but the ultimate is an exponential cone like Duevel uses higher up it's range.

In my experience omni's can be excellent if done right but I have never heard one done with a FR. Seems to be the ideal solution imo apart from the beaming top end and successfully redistributing it.
 
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I built some 'omnis' in the 1970s based on a design published in Electronics Australia magazine. If I recall correctly it was a bass reflex design of about 60 litres with a Philips 10" paper collinear cone bass driver and a Philips 1" dome tweeter, coaxially mounted. Like the picture in the OP the two drivers faced upwards into an exponential director/diffusor, in this case made from cardboard sides and filled with polyurethane foam, which I had the fun of mixing and watching it foam up to fill and solidify the director. I was able to find a manufacturer who sold me a litre or so of the two components to make the urethan foam, which I took home in a couple of Coke bottles.

The speakers were essentially omnidirectional in the horizontal plane, which made background music very tolerant of listening position. They weren't so good for critical listening, unfortunately, because ultimately omnidirectional loudspeakers sound unnatural in real rooms. There will be reflections of sibilance from all walls, for example; this is quite contrary to real acoustic performances where the sibilance from a trumpet or vocal only goes in one direction, and that's usually towards the listener, not away.
 
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With the omnis that I'm currently using I have them as far from the rear wall as I ( at least my ears ) am from the speakers, also the speakers have slightly reduced treble, so I don't have any problems with reflections. Also my listening room is rather cluttered ( a bit of an understatement ). If I did have problems I'd stick so foam absorbers on the speakers ( as illustrated in the above diagram ) to turn them into " half omnis ", or perhaps more precisely half radials - I'd consider them omnidirectional in the bass, hemispherical in the upper midrange, and radial in the highs.
I find my current omnis to be closer to " live " than any other speaker that I've heard, however I think that's down to the construction ( 4.5 KG of iron bolted to the magnet and a light weight double wall upper chamber ) resulting in a very uncoloured sound, with almost all sound coming from the driver cone rather than some from the cone and some from enclosure vibrations.
Perhaps I should have a go at copying the Band and Olufsen acoustic lens, but I prefer the sound to be coming directly from the driver, rather than deflected.
 
Hey Cracked Case, how do your speakers perform if using only one, playing mono?

I’m a single speaker mono kind of guy and have been contemplating a half-omni / radial as a better option of my big boffle speaker. I’m not an anti-stereo loonie or anything, In my living room I just don’t want to be ‘fighting’ the room with my set up or listening pisition and mono keeps life simple.
 
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Hey Cracked Case, how do your speakers perform if using only one, playing mono?

I’m a single speaker mono kind of guy and have been contemplating a half-omni / radial as a better option of my big boffle speaker. I’m not an anti-stereo loonie or anything, In my living room I just don’t want to be ‘fighting’ the room with my set up or listening pisition and mono keeps life simple.

I think the best way for me to test that idea would be to play a mono CD, unplugging one of my in line actuators . I think I have some cream on mono, Robert Johnston is a mono CD, although not the ultimate in hifi quality. I have though of using a " mono with stereo wide " type thing by using rear facing tweeters with some time delay, possibly provided by transformer time lag.