8rda+ and logitech z-640's

[mpa4712]

Just got a new speaker setup seein as my old ones just broke. I like to use my sub for a footrest, and after a year or so of rocking, the connector that held the wires in broke off the pcb
so i picked up some logitech z-640's

the problem is settin them up right.

what i did was i ran the speaker setup wiz. everything came outa the right channel. When i enabled dolby surround encoding, nothing comes outa my rear speakers at all. It all defaults to the front speakers. Was wondering why? ANd how can i fix this? Im tryin to watch all the good movies with the directional sound, but i dont think im hearin it quite as well as i should.


Thanks,
mark

[mpa4712]

anyone?

[mpa4712]

guess that sounds kinda off..WHen i ran the speaker setup, everything came out of the channel it was supposed to, not all out the right channel.

[BackBonE]

How do you connect them?

[mpa4712]

they connect thru the onboard connectors...i use all three of them, the pink, blue,and the green.

[Aedan]

As far as I understand, the Logitech Z-640s do not have a Dolby Surround decoder. Nor, despite what the box might suggest, do they have a Dolby Digital decoder.

Dolby Surround encodes the rear and center channels onto a stereo signal. Hence, if you enable it and don't have a decoder for it, you'll only get a stereo signal out of the board.

So, go back and turn Dolby Surround and Dolby Digital off, as your speakers do not support those features natively. Instead, they rely on your computer to decode any such signals for them.

Presumably, you also turned on the settings that allow the input jacks (ie, mic and line in) to be used as outputs for center/sub and rear channels.

[mpa4712]

Well, then how exactly do i use the dobly digital, says on the box they are compatable

[Aedan]

Here's a snippet from the requirements section on Logitech's web site.

System Requirements
PC
For 5.1 surround sound: any 4 or 6 channel sound card
For Dolby Digital 5.1 sound: sound card or software DVD player with built-in Dolby Digital decoding

In other words, the speakers themselves can't decode anything, which is not surprising at their price point. They rely on your PC to decode the Dolby Digital stream for them.

Dolby Digital (and DTS) are presented over either a single fibre, or over a single coax cable. If the speakers don't have a digital input, then there's no way they can decode a digital signal like Dolby Digital or DTS.