SMART INVOLVE ENCODE- test tones!!

[chucky3042]

I've been playing these through the basic RM decoder in my kenwood 9940, it treats them exactly like QS(both smart and "dumb"). The basic RM seperation is hilarious, for example, a tone in RL on the 9940 results as FR vu meter down, FL+ RR vu meters straight up and RL is 3db higher, and so on in all directions. If the tones included the 4 phantom centers(8 positions) it would be a more complete/interesting comparison between the smart and "dumb" encodings.

I will ask Dave the Bitch to provide the centers!!

 

[par4ken]

Dear All

I was misinformed by Dave the Bitch the sample track above was in DUMB fixed parameter Involve format- OOOPS sorry chaps.

OK here is a link to 4 test tones, sine waves in smart and fixed encode, and pink noise in smart and fixed encode, for your delight.

https://drive.google.com/drive/folders/1nfYC3dS0MfMgO_CQ8BEeVRMHCTRPlFid?usp=sharing
I think I have been a good boy this time and made it available to all, if not kick my fat lazy butt.

To cut a long story short here below is a screenshot of Dumb fixed parameter Involve encode in tone packets:

View attachment 55844

RL..................................................................................FL.......................................................................FR.......................................................................RR.........................................

As you can see the blend/ mix is 0.21 in magnitude meaning in stereo its around 13.5 db separation, remember my 12 db is all you can detect rule, don't believe me try it! When you decode it into surround you get a MINIMUM of 12 db separation in all directions. I cannot find the decode results tonight- give me a day or two. Advantage is it sounds normal for stereo and surround - providing you are not in a numbers pissing contest that we have never been!

Hey on a QS source signal we get 35 - 40 db separation in all directions but the downside is the stereo QS encode sounds compressed in terms of image to a puny 6 - 8 db or so.

So below is a screenshot of SMART Involve encode variable parameter packet tone:

View attachment 55847

RL........................................................................FL......................................................................FR..........................................................................RR........................................

Spot the difference?
The mix/ blend increases to a peak value of 0.41 only when surround (rear ) information is present. If its just plan old boring bog vanilla stereo the encode reduces the blend parameter to the lower extreme 0.21. Now you gotta remember its doing this in a triband manner so when one frequency band might have surround but another might just be stereo - at all times we are adjusting the psychoacoustic parameters of the matrix. Please note that us humans are really bad at perceiving multiple directions of SIMULTANEOUS similar frequency band tones so in those instances we need all the help we can get in terms of matrix separation (also thats the hardest thing for a matrix encoder to split up ) . On normal music where things are peaking all over the place in different frequency bands at different times both human hearing can separate well and the matrix encoders eat it for breakfast.

So SMART Involve encode is the first (to my knowledge) variable mix encode parameter triband encoder. The end result is that the stereo sounds like stereo and the separation (worst case) is below:

View attachment 55849

The bottom one is Smart involve encode, as you can see you get a theoretical worst case separation of 12 db front to rear in 2 instances but in practice it never really happens as these tests were on FIXED TONES - not music where the full 0.41 parameter would be mostly in use and so the actual overall result would be the average of the two above separation tables. Hope you guys get my point, I know its confusing and my head also hurts this time of night (12.30 am ).

Oh its all patented - full PCT in multiple countries!!!

Nigh Nigh

It's nice to see an explanation of how your smart encode works. The effect on decoding gives only 12dB across the front which will move the left front image to the right slightly, may not be that big of a deal though. Interesting that the encoder is triband as well, that should be a good match for the triband decoding. I recall reading about Circle Surround (DSP) encoding and they were making similar claims as you guys, about their encode system not affecting the stereo image.

 

[chucky3042]

It's nice to see an explanation of how your smart encode works. The effect on decoding gives only 12dB across the front which will move the left front image to the right slightly, may not be that big of a deal though. Interesting that the encoder is triband as well, that should be a good match for the triband decoding. I recall reading about Circle Surround (DSP) encoding and they were making similar claims as you guys, about their encode system not affecting the stereo image.

The 12 db thing is a momentary thing in certain circumstances where the human ear/ head is less sensitive to separation - most of the time the parameter is closer to 0.41 where you get the full separation.