Simple corner speaker: reasonable?

[zintolo]

The WLs are so long that at my fixed 120 Hz XO, the driver, vent, corner combo was basically an LF infinite array, so in the lower mids down to cutoff it came closest to a live concert's high pressure cocoon

That would be great! ...the amp will need to be really quiet not to hear its hum!

Unfortunately, unless it's really large it will only deflect HF, so unless you want max amount of it to comb filter with the driver, don't recommend using it.

It is needed to be as wide as lambda/4?

Better to make an inverted taper going all the way to the ceiling with triangulated notches on each side big enough to at least [crudely] maintain, if not actually continue, its flare factor [conical, expo/whatever], frequency [horn cutoff [Fc], i.e. normally don't want to audibly 'pinch' it;

Why do you suggest it to be inverter taper?

so for corner loading, design a full size horn and only use an 1/8th WL long 'slice' out of it or as much as your ceiling height, room volume [terminus/mouth] will allow.

I will try to design something and then ask for suggestion. I'm a real neophyte at hornresp, but I will try.

 

[zintolo]

a single board can be used in some instances

Indeed, most of mine were and all but the first few of mine were horn tapered.

Thanks, I will try to sketch something this way too, maybe folded?
Will those need stuffing too?

 

[talaerts]

Alternatively if it is ok that the speaker protrudes more into the living room, the Big Fun horn is explicitely designed for corner placement, the corner walls extending the horn. Was designed for a Lowther but I expect one of the modern fostex fe206nv to work nicely as well. Big fun horn will give surprisingly deep bass too.
There is a smaller All Fun horn sibling as well.

bigfunht

Here is a nice looking multilayer cnc’d version of it:


Or from the designer:

 

[zintolo]

Thanks for the link talaerts,
I will read it, but I would prefer to use the full heigh of the corner and less footprint, as the room is around 5x3 meters and I need to fit a table for tests plus instruments.

 

[AllenB]

It is needed to be as wide as lambda/4?

Since you ask, here is how to fold it.

Also a real life example.

 

[zintolo]

I can propose it, as it is in the photo, for the garden. 😀
What was that for?

 

[AllenB]

It is a microwave waveguide (antenna) 😉

 

[talaerts]

Thanks for the link talaerts,
I will read it, but I would prefer to use the full heigh of the corner and less footprint, as the room is around 5x3 meters and I need to fit a table for tests plus instruments.

You could probably imagine another fold which goes up instead of at the back and then still uses the corner as the last part of the horn, necessitating less footprint into the room. Interesting. Must revisit this idea if i ever make the big fun horn myself.

 

[zintolo]

It is a microwave waveguide (antenna) 😉

...so I was right: it can be placed in the garden pointing the swimming pool to heat up the water! 😀

 

[zintolo]

You could probably imagine another fold which goes up instead of at the back and then still uses the corner as the last part of the horn, necessitating less footprint into the room. Interesting. Must revisit this idea if i ever make the big fun horn myself.

I will think about it and propose here some ideas. That is "my" room so I can give space to kynky ideas. I like being in the listening room that is the speaker itself.

Like a Möbius speaker.

 

[zintolo]

I have few questions that I think they need alot of theory behind, but maybe there can be some basic guidelines to understand how to do things:
- is there a limit in the angle of the cone?
- how the angle of the cone influences the sound?
- is there a limit in the angle between two sections of the cone or two surfaces in a folded BLH?
- once designed the horn, can I use these rules ( Spreadsheet for Folded Horn Layouts... ) to design then the folded one?

I pose the questions about the angles, because when I was 15 I designed some expansion chambers for my 50cc moped, and for that purpose (resonant diverting-converging cones) there was need not to exceed a certain diverting angle between two contiguous sections.

Thanks!

 

[zintolo]

I sell damping kits, but you should check with Stefan at KJF.

Thanks Dave, unfortunately shipping costs are more than the stuff itself nowadays, and this makes the stuff cost 50% of the wooden cabinet built. May I ask some hints to find the stuffing locally?

I've found 1 cm Dacron, can it be of any use?

Thanks

 

[planet10]

You need some sort of felt, cotton or wool preferred, and some polystuff. Dacron can come as a quilt like material or as loose fill You want the second.

dave

 

[zintolo]

Thanks Dave,
I will post here some links to be sure I’ll buy the right stuff.

Roberto

 

[jeffryr]

It is a microwave waveguide (antenna) 😉

This is only about 15 minutes away from where I live. I worked for the phone company in one way or another for 35 years, somehow never got around to visiting the antenna (which is now a National Historic Landmark) until last spring. Kind of big to fit into the living room, though...

 

[zintolo]

Thanks to Dave I've learned something more about horn design: https://www.diyaudio.com/community/threads/a-silbury-build.347611/post-6969812
and I would like to ask if Alpair 10.3 can be used in this scenario, or being able to have huge volumes in the corners, they perform better with bigger speakers like 12" or 15"?

I was thinking to fix these to the wall with screws every 30 cm and a gasket in it: https://www.leroymerlin.it/prodotti...ato-pino-2-1-m-x-24-mm-sp-24-mm-33013470.html
and then add screws and gasket on the wooden panel as well to fix it to the wooden supports.

Being the distance floor-ceiling around 2,7 meters, could I tune it to 20 Hz going from ceiling to floor and back?
Mouth, being corner loaded, can have an area of 29246 cm2, that is a square of 171 cm.

Considering the suggestion for the ceining given by AllenB here: https://www.diyaudio.com/community/threads/simple-corner-speaker-reasonable.379883/post-6862585 what is the area of the mouth? The section given by the sides of the angled part in the corner of the ceiling and the higher part of the front panel?

 

[AllenB]

I did this so many years ago so I can't remember the details. I had a normal box speaker on a stand, back loaded horn leading out the back and diagonally down toward the floor. It might have been 50-80cm long, maybe 30cm across at the mouth. I tuned it by moving the mouth closer or further from the triangular reflector which was maybe 50cm on a side.

Because I used the corner I had to find the best place to sit, but when I did the bass was smooth and strong to 20Hz out of a 6.5" woofer.

 

[zintolo]

Thanks allenB! Can I ask you a sketch to better understand it?

Here I was thinking to a shape like a triangular based metronome to reach the ceiling with the tip without affecting the area of the mouth (that will be again on the ceiling), with the front baffle extended to the walls of the corner to create the second half of the horn "floor to ceiling". Is it too much?

I was thinking it that way because it is quite simple to be built and removed to be stuffed.

 

[AllenB]

Is it too much? No, I don't like to say that. Just try to understand what you do so that you don't create shapes that are unnecessary and keep your paths clean. Make the best of your space.. If you can calculate your horn all the way from the drivers out into the room, you can run it in hornresp.

 

[tmuikku]

Nice concept AllenB!