Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems Suitability of Trifield algorithm for setting up a rear center channel using 2nd proc

I have a 568 and presently use a Smart CS-Jr for creating a rear center channel from the signals of the 568 right and left rear surround channels. Is the algorithm of Trifield suitable for synthesizing a rear center channel for video as well as audio sources? How does that compare with a circle surround or dolby prologic matrix for creating a "center" channel? My main 568 preset will be either Super, which has strong rear surround info or the DTS/DD 5.1 sources. The rear center channel will be created by using a Meridian 565 outputting a right, center and left Trifield matrix.
http://www.hometheaterhifi.com/volume_7_1/smart-theater-cs3x-processor-march-2000.html




[This message has been edited by mburnstein (edited 10-23-2002).]

Is this on top of using EX already? The whole reason for the Smart was so you could have EX w/o an EX processor.

I don't have/or use an 568 EX mode. I have the 568 stereo rear surround channels and have set up the rear center channel like Brian Florian did in his review.I'm wondering if the Trifield would be better than the Circle Surround process for a rear center channel matrix.
Thanks, Mark

Hi,

Why don't you just use the 7.1 from Meridian.
I used a CS a while ago, but with 568 I dumped the unit as fast as possible.

Greetings,
Frank

I am using 7.1 Meridian: My set up is basic 568 Meridian 7.1 stereo sides & stereo rears plus rear center channel(presently derived by Smart Devices CS-JR)= 8.1


I'm not using a rear EX mode in the 568 rear surround. I use mainly Super for PCM whenever there is no DD or DTS. So presently, I have rear stereo surrounds which drive the Smart CS-Jr to derive the rear center channel. I'm wondering if I will have a better result by removing the CS-Jr and replacing it with an inexpensive 565. The analogue input of the 565 will come from the surround rear channel analogue outputs of the 568. I'd select Trifield DSP mode in the 565. Any idea how that would perform then when using a PCM source in the 568 and selecting 568 Super, which has a lot of information going to all channels, including the rear surrounds. This inputted to the 565 will give me the Trifield mode for my back three speakers. Any thoughts? I definitely do not use an EX set up where the rears become mono and the sides become the (rear)surrounds.


[This message has been edited by mburnstein (edited 10-23-2002).]

I would presume Trifield would be better since instead of "steering" the sound to the rear center channel as in those "logic" processors, it would re-distribute the rear 2ch's sound into 3 channels. Plus, it will modify phase information to the L&R in order to enhance directional accoustics. Although I don't think the EQ settings apply anymore.

If you use steering methodlogy, monophonic ambience might be produced only by the center speaker. And any shifting sound would cause the rear soundstage to collapse whenever it shifts from off-center to center.

People might say the steering involved will provide better imaging since center sound source will be produced by one speaker, but we are not talking about EX source where rear center is dead center.

"People might say the steering involved will provide better imaging since center sound source will be produced by one speaker, but we are not talking about EX source where rear center is dead center."

Right Lwang! I'm not dealing with play back of sources with a flag for the rear center channel, as first of all I don't want a set up that does see a rear center channel flag but forces me to have mono rear surrounds and move the true rear surrounds to the side speakers-if that is what a Meridian EX does-I don't want that! Do you think the way Trifield works to take a stereo signal and create 3 channels, is there any risk of this not matching the rear surround action on the video playback?

I think Meridian's EZ in 7.1 uses the 2 rears the way 6.1 EX would use the center speaker.

Using steering type of rear surround, any sound source that pans from left to right would go from 2 speaker mode (balance between the L&R speaker with emphasis on one of the channel,) to center speaker sound only, then to 2 speaker mode. Causing a unatural shift in sound, which is the hallmark of DPL.

Trifield will only enhance the playback of the sound. Unless it is EX encoded, where they have intentionally put the rear center sound and expect you to only hear that single rear cente speaker (like that little ballon man in the THX logo demo going to the center rear and doing his thing.) Besides that, anything that involves sound from both L&R surround, Trifield mode would be better.

Thanks lwang--I'll set it up this weekend!!!