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Old 8th June 2006, 09:39   #8  |  Link
Rockaria
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Join Date: Mar 2005
Location: The Sun, somewhere around
Posts: 553
Quote:
Originally Posted by 3dsnar
OK, thanks all of you for votes.
BTW. The original signal is provided too.
But after my post in other thread, without any notice or acknowledgement.
http://forum.doom9.org/showpost.php?...9&postcount=63
Quote:
You might want to add two more models to fully reflect the discussions in the related threads:
Lt = FL{0°} + 0.7071 C{0°} + 0.7071 LFE{0°} + 0.866 BL{-90°} + 0.5 BR{-90°}
Rt = FR{0°} + 0.7071 C{0°} + 0.7071 LFE{0°} + 0.5 BL{90°} + 0.866 BR{90°}
and
Lt = FL{0°} + 0.7071 C{0°} + 0.7071 LFE{0°} + 0.866 SL{180°} + 0.5 SR{0°}
Rt = FR{0°} + 0.7071 C{0°} + 0.7071 LFE{0°} + 0.5 SL{0°} + 0.866 SR{180°}
...
You might also want to test with original 6ch(mp4 format) vs dpl II mix(music + speaker test clip), to compare reasonably.
The FFDShow can switch between PCM/AC3 in digital out mode on the fly making it easy to compare.
As I said many times, the speaker test clip is most generous on any models(more than 95% of the seperation quality).

Also the matrices values(Ls1,Ls2,Rs1,Rs2....) might affect the seperation quality by the phase shift degree change.
Comparing the Wikipedia matrix with the current one would be reasonable(also making it reasonable using the variable reference than the values).

So far, the fifthelem_B showed noticeable better seperation, but the test is not setup to compare the seperation fidelity(original vs DPL II).
Quote:
Originally Posted by 3dsnar
Yes, A is 180 deg phase shift (the simpler approach),
B is 90 deg. phase shift.
Can you provide the proof in a source format(no dll)?
Quote:
Originally Posted by 3dsnar
The sign variations are not important, because they result
in phase invertion in the decoded signal and do not affect the separation (as Tebasuna already noticed). Therefore A and B are enough to distinguish between 90 and 180 phase shifts.
Again, it's just your very dangerouse assumption.
You can test it with FFDShow which can adjust the matrix value with the sign.
It shows no difference only with the simplest speaker test file.
Also prove exactly which Tebasuna's observations concure your assumptions.

Quote:
Originally Posted by 3dsnar
I agree with Scharfis that the 90 deg phase shift should have been prepared with the same sign style, to be fully consistent with the 180 deg. shift. Maybe next time
also check my quote above. indeed, the polls feels like something public.
Quote:
Originally Posted by 3dsnar
(early) conclusions.
1) There is a noticable difference between the 90 deg phase shift and 180 deg phase shift : agreed.
2) 90 deg seem to produce significantly worst results, thus probably the DPLII downmixing equation is based on 180 deg. shifts (simple sign change).
I agree again we are using totally differernt languages. Apparently it seems what you wanna see.
---
Quote:
Originally Posted by 3dsnar
BTW. Please test Aud-X DSfilter DPLII decoder (or rather DPLII decoder simulation),
by sending the output as AC3 through SPDIF to your HT amps.
I am curious of your opinions and especially your thoughts regarding its quality vs certified dolby decoders quality
My independant Ad. :
Sorry, unfortunately, I am very much satisfied with the FFDShow with probably 1000% of proven better features and stability.
I also believe they will provide the DPL II encoding with 90 deg. phase shift very soon(with current adjustable matrix).
__________________
u know everything in the end, or now if aligned... no right(x).right(y) pls. it's confusing... : phase-shift /Jun.2006
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