Logitech Z560's and the M3D option...whats it supposed to do exactly?

[dpk777]

Is it supposed to produce more realism?

when I turn it on it seems to just weaken the sound in the rear speakers.

Is there a proper way to use it?

 

[jamesbond007]

Quoted from www.3dss.com,

What about this M3D Matrix Technology?

If you have ever put a standard stereo source through a Pro Logic decoder then you will have a good idea of what the M3D Matrix technology sound like. M3D Matrix technology is a method of extracting the natural hall ambience hidden in 2 channel music sources to present a realistic surround sound effect with no artificial reverb or echo. It has no impact on the front channel output.

With M3D mode enabled the rear inputs of the Z-560 are completely disabled, so you won't want to use the M3D effects on any true 4 channel source material. In this mode the rear volume control instead allows you to set the strength of the M3D effects sent to the rear speakers.

The key differences from the Pro Logic effect and the reason why I think it sounds clearly better than the Pro Logic generated surround channel from stereo sources is, unlike Pro Logic, the M3D effect is not frequency limited so there is good bass and high frequency performance. That's not to say that high frequency response on the ambient surround effects is that important but to me it makes a notable positive difference. Just as with Pro Logic the M3D effect is always a mono effect, that is regardless of the source originating from the left or right channel the surround effect will come equally from both channels. That's unlike Creative's CMSS Music Mode, which, while sharing the Pro Logic frequency limitation, is a stereo surround effect. The CMSS Music mode can be found on the DTT2500, DTT3500 and likely Inspire 5700 speaker systems. QSound's QMSS, found on sound cards such as the Acoustic Edge, will give the best of both worlds with a full frequency stereo effect on the generated surround channels.

Getting back to M3D, just as with a Pro Logic decoder, any material that is in exact center will not play from the surround channels with M3D enabled. The result is you will often get a nice effect with any centered vocals staying with only the front speakers and just some of the instruments duplicated into the M3D generated surround channel.

Note that while there is clearly some appropriate front, center and surround channel separation on native Pro Logic material it is not a Pro Logic decoder and as such as not nearly as effective as such a decoder when it comes to full surround/front channel separation. That is, unlike an actual Pro Logic decoder there is a lot of leakage of front channel material into the surrounds and vice versa.

More information and the source of this paste is located here.

Good luck and enjoy your awesome speakers!