Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems Trifield

Damon said:

>depth, width, center channel volume, and frequency EQ<

If the speaker calibration is done with an SPL, and/or a calibration disc like Digital Video Essentials, and provided all speakers are correctly set at the same level, what is the need to adjust the center speaker volume in Trifield? Shouldn't it be already calibrated to sound at the same level as the L/R channels?

I understand the need to tweak depth, width and so on, but center channel volume? Please explain.

Also:

>(I set the EQ at full range, which prevents the "dull", rolled off sound that some people hear).<

What is the EQ full range setting for, and how it affetcs the sound? I know it goes from Flat to EQ1-3, but that's it.

And on that note, anybody know what the Rear LPF setting differences; spome of these changes are so subtle, they are difficult to pinpoint.

Cheers!!!!!

George (Mills), to answer your question, initially I did a speaker calibration with the SPL meter and redid a few more times, but since I now have all speakers set to small it doesn't really matter I guess. Yesterday, I discovered the program "sizecalc.exe" which was installed with the new Meridian Configuration software, and played a little with it. Its calculations confirm my initial speaker calibrations (size 17 for the 804's and 20 for the sub). As for MRC, I continue to change things (experiment) in the room (testing for better sound / placement) so I frequently do an MRC to see if the difference is for better or worse (ie moving a couch or a bookself), and till now the sound has improved quite a bit by simply adjusting furniture ..

Regarding the surrounds, even with a 10db+ setting, you can hardly hear them - the only noticable difference is that the overall sound seems to be more full? around you? I don't know how to actually describe it. Don't know if this is correct though.

Still, I would want to know really what all these DSP settings do, how they should be adjusted, and some guidelines to the whole thing. For some reason I feel that my system could use some more fine tuning (maybe because I've seen the difference with the +10db in the surrounds?).

Regards
Costas

BTW, have a look at http://www.trifield.co.uk/Audio.swf

No documentation there either

Surely a lawsuit in the making there...

> What is the EQ full range setting for, and how it affetcs the sound? I know it goes from Flat to EQ1-3, but that's it.

A center speaker is made for movies not music. So it is made to enhance the dialog of a movie. The EQ setting tries to reverse that process. In my experience for Trifield to really work you must have exactly same speaker as the front and not just the center speaker in that speakers series. The Flat setting is for exactly that setup.

Kacos,

No insult intended, but your replies indicate you may be confused.

You said you set your speakers all small and because of that calibration doesn't matter. Of course it does !!!

There are 3 things you need to adjust.

Gain - with the SPL.
Distance - With a ruler
Speaker size - With Size Calc.

Speaker size only effects a bass limiter safety. Which I defeat.

After you got all that done. Run your the Room Correction.

You may have your own preference to turn the rears up a tad but 10db is a lot.

George, no insult taken. The most recent speaker calibration (gain etc) I did was two weeks ago when I installed the new software. Speaker placement is (and copied in the Msetup) done with a "long ruler" also. Or do you mean that I must run a calibration everytime I change the placement of the furniture..? And then run the MRC?

As for the +10db, I understand it it too much since its the highest possible setting
I am simply experimenting - but would like to know more thus my questions on documentation etc.

Regards
Costas

I doubt it:

From the installation guide of the G68 controller's pdf page 4/70:

You can see the patent here and full text here .
from here .

This comes from the ambisonics website

I also found this page with interesting articles in multichannel sound from Gerzon archive at audiosignal.co.uk



[This message has been edited by kacos (edited 05-30-2005).]

Gentlemen and Ladies, regards Trifield;

Let your ears decide.

You will probably find that there is no right or wrong.

If it sounds good in your room with your material to YOU, then thats the correct setting for your system at this time!
Untill you think it isnt.

Then you can of course change it.

Above all enjoy your Music/Movies

Chris.

Bob! You big fraud! I thought Trifield was yours!

Cheers

George

Me too.

Good find Kacos.

I also found this page which lists the Meridian processors
http://www.Trifield.co.uk/Multi-speaker.swf


[This message has been edited by George Mills (edited 05-31-2005).]

Last night I recalibrated the speakers, did an MRC again, and played again with Mr. Bob's Trifield setting - changed center depth from 0,5 (default) to 1, Center EQ from EQ1 (default)to flat, and rear level (default=0) to 5. The integration of the L/R B&W804's with the B&W HTM1 is now so seamless that you can not distinguish if you have a speaker at center or if it is stereo playing. Sound stage much wider, so is depth. Much much better sound overall.

Heard many disks afterwards which sounded way better than before, but I was impressed with one: I am not sure what sort of recording process Vanessa Mae's latest CD has, but it sort of sounds as its DTS 5.1 somehow ..

BTW, M's Trifield is probably the only implementation in consumer products out there (hence Meridian's own Trifield). And there is a slight possibility that Yamaha has an implementation of "Tri-Field" which I am not sure if it its the same or not. The only other products I found using Trifield algorithms are professional encoding hardware or software.