Stereophonic Sound from a Single Loudspeaker

[Elias]

Originally Posted by soundaatma

Hello Elias,
Good work here. Can you please direct me to the exact wiring scheme that you used to implement the "0.5" attenuation.

There are some similarities here to the Haas effect to extract surround ambient signals using L-R or R-L and sent to surround speakers.

Here the schematic I use for SSS. Matrix x=0.5. And there is the psychoacoustic filter to steer the energy at high freqs.


Yes SSS increases the perception of 'surround' since for example left side element signal is:
L - 0.5*R = 0.5*( L + (L - R) )
which means there is the 'raw' left signal and 'surround' signal with equal amplitude.


- Elias

[soundaatma]

Thanks Elias. What values are you using for the resistor and capacitor Rps and Cps. Thanks.

[Elias]

Originally Posted by soundaatma

Thanks Elias. What values are you using for the resistor and capacitor Rps and Cps. Thanks.

The component values are 'hidden' here:
Elias Pekonen Home Page - Stereophonic Sound from a Single Speaker


But the answer may depend, as usual. It can depend on the driver's high freq response, and the room.

Good starting point is to choose Rps as about half of the driver impedance. The Cps value can then be used to tune the corner frequency, and is best found either by measurements or listening tests.

For 8 ohm driver one can start with Rps = 4.7ohm and Cps = 4.7uF. But as said, it depends


- Elias

[soundaatma]

Thanks Elias, I discovered the hidden fine print on your website !

[Elias]

Interest on component values indicates you are building one ?

[soundaatma]

Hmmm..i am planning on a portable laptop speaker, with 3 widerangers, run full BW. Something like a mini "soundbar"
Thanks for your help Elias.

[norman bates]

Hopefully your speakers have a flat resistive impedance curve.....................

Maybe 3 x fx120's.

I'd toss the cap and use a pot around the mono center speaker in post 381.

Keep your head the same distance to all 3 speakers and you'd have a winner.

I think I'll build something to test it.

A coffee table listener should work well.

[norman bates]

car stereo review 1990

How To - Car Stereo - How To Install A Center Channel

[Elias]

Originally Posted by norman bates

I'd toss the cap and use a pot around the mono center speaker in post 381.

The capacitor may turn to be an essential part of the system.

It has the effect at high freqs of reducing the center element and boosting the side elements. This seems to be due to psychoacoustic requirements that the capacitor is to be used. It can be considered as energy steering of the stereo field.

And, at low freqs where the capacitor impedance is high the three elements work as a vector steering of the stereo field.

It is similar behaviour to Gerzon Ambisonics, which is based on low freq vector theory and high freq energy theory.


Now if you leave the capacitor out and use some resistor the frequency dependent nature of the function is no longer fullfilled.


- Elias

[norman bates]

true, it would be a simple summed mono fill speaker.

But I've heard it sounds great though.