Stereophonic Sound from a Single Loudspeaker

Phase is a vector

Here is the Mexican with a bad English (hard to explain for me this concept)
My personal poit of view

The major problem is the back wave that is enclosed and it will be sumed to the other channel inside the box even with separate chambers,

My proponsal is to manage that backwave with a direction (vector, not scalar magnitude) to be added to the front wave to the corresponded side even with low end frequencies (2 woofers)


I'll post my latest pre-prototypes (12 years almost 80 pre-prototypes)


Saludos desde Mexico:D
 
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Many TV bar kind of the speakers have some kind of stereo image processor that widen the stereo image feeding inverted signal to the other side of the speaker, but this stereo effect processor makes me feel sea sickness...

In my experience the SSS sounded quite natural and coherent. Although I found the filter quite fiddly to set up correctly, especially crossing over to a mono bass mid woofer. Never managed to get it quite right and moved on to other builds. Working with a higher efficiency driver like the 3fe22 and turning the mid driver to the front wall or upfiring sounds like it could be interesting in the SSS configuration. Just a hunch, based on my experience.

I thought about DSP version, but getting the matrix wiring working made my head hurt.
 
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So it is done:) I am quite happy with the result this time. No psycho-acoustic filter, I will experiment with cloth and 3D printed diffusers instead. With a piece of random cloth I had around it seemed to work really well.
 

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I just saw these on the web, have not seen them in person nor heard them.
https://image-us.samsung.com/Samsun...20/FinalFile-2020-Giga-Spec-Sheet-T70_124.pdf

1648404235244.png


Samsung is trying to do a one box stereo speaker. The largest of the three models has an up firing 10" woofer with some unknown 2 way left and right. The smaller models seem to be 2 way only. To me the angle looks too wide for good stereo, but maybe they have some sort of matrix or DSP to deal with that. They are too ugly for me, although the "party lights" are tempting. :p However it is an interesting approach and could serve as inspiration for a DIY project.
 
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have not seen them in person nor heard them.
Well now I have seen them in person, they are much larger than I expected. The 70 model is a beast. The also look much nicer than I expected, a quality build. Not fancy, they just appear well made and more sober than you think for a party machine. The angle between left and right is more severe than it looked in the photos, not sure how that will sound. Alas I did not get to hear them, but I will go down the mountain again to have a listen.

Yep, I'm going to completely audio nerd this one. I'll take a playlist of demo tracks on my phone. Normal stereo, wide stereo, mono and spoken voice. I want to know how well it renders stereo and mono, considering the very wide angle.
 
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FWIW, I find switching pink noise from left to centre to right to be a good indicator.

I did an experiment yesterday on this subject. I had thought a pair of dipole drivers mounted at 90 degrees would give some useful stereo width by leveraging the back wall reflection (which would have discrete left and right zones). The precedence effect defeated that one - the sound was always obviously coming from the speakers, but there was some hint of "spaciousness". Nowhere near enough for a proper stereo image, though.

Chris
 
In my experience the SSS sounded quite natural and coherent. Although I found the filter quite fiddly to set up correctly, especially crossing over to a mono bass mid woofer. Never managed to get it quite right and moved on to other builds. Working with a higher efficiency driver like the 3fe22 and turning the mid driver to the front wall or upfiring sounds like it could be interesting in the SSS configuration. Just a hunch, based on my experience.

I thought about DSP version, but getting the matrix wiring working made my head hurt.
I think DSP version would be the best for such speaker. It is just not enough freedom with passive solutions. I played quite a lot with different single speaker stereo techniques. But the best i have found is with MID/SIDE stereo manipulations included. here is the link https://www.baffless.com/single-speaker-stereo-1 for a short explanation.
 
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