So now that Xebra has sound interpolation

[drhycodan]

How come I don't hear any sound differences between the new version with interpolation and the old one without?

[jvhellraiser]

Sounds better the old releases have cracks on the audio lots of them with this new release
that is fix i still say he should work on the nearest option or maybe fix Progresive mode that makes the emulator go slow and nearest option that when is select it makes the emulation look like it came from the trash can.

[Ilya-v]

Download latest xebra 5th Jan 2011.

Try these settings to enable Interpolation.

Sound Output:

N = 2
a1_ = -2
a2_ = 0

b0_ = 1
b1_ = 1
b2_ = 1

Don't ask me what those numbers mean because I have no idea.

P.S
The PSX don't actually have a Gaussian Interpolation filter,
its the effect of its DA converter that makes it sound like this (duller).

This is exactly what Dr. Hell emulated (NOT Gaussian filter like all the other emulators).
So with these settings we've got the closest thing to the real console.

Cheers.

[drhycodan]

Don't enable Nearest in the video, it only disables the bilinear filtering. I don't know who told you to enable Nearest but it's only needed for old pc's that can't handle bilinear filtering.

[Ilya-v]

Vise-Versa, your pc needs more power without the Billiner filtering.
Nearest multiplier Doubles, Triples, Quadruples etc.. the resolution till it fits you monitor.
Without it, the picture is just Stretched to your monitor (thats why its blurry).

With Nearest On, you actually see the real picture that the console/emu outputs.

[hattori]

Look at http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt.
From this document, code of the filter is only one equation.

y[n] = (b0 / a0) * x[n] + (b1 / a0) * x[n - 1] + (b2 / a0) * x[n - 2] - (a1 / a0) * y[n - 1] - (a2 / a0) * y[n - 2]; (Eq 4)

To make coefficients to be integer, this equation is transformed and Xebra uses

b0_ = (int) ((1 << N) * (b0 / a0));
b1_ = (int) ((1 << N) * (b1 / a0));
...
y[n] = (b0_ * x[n] + b1_ * x[n - 1] + b2_ * x[n - 2] - a1_ * y[n - 1] - a2_ * y[n - 2]) >> N;

You have to ...

(1) decide parameters ... Fs(=44100), f0, dBgain, Q
(2) calculate intermediate variables ... A, w0, cos(w0), sin(w0), alpha
(3) calculate b0, b1, b2, a0, a1, a2

Probably, type LPF is suitable.

(4) decide N
(5) calculate b0_, b1_, b2_, a1_, a2_

b0_ = (int) ((1 << N) * (b0 / a0));
b1_ = (int) ((1 << N) * (b1 / a0));
...

[Ilya-v]

hattori.

This is VERY complicated for the avarage user to calculate the desired results.

What we need is a SIMPLICITY.

y[n] = (b0 / a0) * x[n] + (b1 / a0) * x[n - 1] + (b2 / a0) * x[n - 2] - (a1 / a0) * y[n - 1] - (a2 / a0) * y[n - 2]; (Eq 4)

This means nothing to a guy that wants to play Mortal Kombat Trilogy and kick some butt.

[shalma]

hopkat:
partly responsibility of gamers too to find coefficients. ones that seem reasonable (like frequency response # by nenolod)
UPSE nenolod.net (http://nenolod.net/projects/upse/)


my question-
if psx doesn't have gaussian (a/d noise like sonic waterfall)
I want my R-G-B! (http://www.disgruntleddesigner.com/chrisc/gotRGB/index.html)

how many consoles have 'fake' output? meaning..
- how different would emus sound like with / without a/d disrupt? would 'fake gaussian' apply to many consoles?
- if snes has gaussian already, would a/d convert add another 'dirty gaussian-like' filter? (medium quality signal?)
- does high quality d/a cable exist for psx? (cleanup signal?) tap raw audio output port and monitor data?
- do consoles have post-output filter that can't be measured / read? (partly thinking of frequency reponse)

sorry. just curious now. don't want to be too greedy :)


must get powerful system someday - bsnes, xebra, (next cycle-accurate emu)

[Judentum]

very nice that xebra/arbex got an own section here!

i agree that this is a bit confusing to calculate for noobs like me, but discuss people, i want to learn more about psx hardware / emulation / xebra. :)

[drhycodan]

If the N, A1, A2, B0, B1, B2 settings need to be set to that value for interpolation to work, why did Dr. Hell default the values differently to disable interpolation? Did he do it on purpose to encourage the users to figure the algorithms out themselves or what?

[masta.g.86]

Testing purposes.

Documentation pending.

[Ilya-v]

GREAT NEWS !!!

Finally, Perfect Sound Interpolation. :thumb:

Check latest version 7th Jan 2011:
NYO$B%C%H$d$m$&$<(J (http://drhell.web.fc2.com/ps1/)
(click the picture at the bottom of the page).

Touch nothing in the Sound Settings.
N should be 0.

* I have recorded my console through the Red/White plugs.
and this version and the Console sounds Exactly the same !!!

You can forget about the N, A1, A2, B0, B1, B2 settings.
Although they are still here to mess with.
N = 0 means no effect.

Many thanks Dr. Hell.

Cheers.

[Kaan]

Thanks for the news. Is that really how a ps1 sounded like? In my mind i remember games sounding more crisp. It has been quite a while though.

[Ilya-v]

Thanks for the news. Is that really how a ps1 sounded like? In my mind i remember games sounding more crisp. It has been quite a while though.

Yes, exacly like this.

The CD music sounds clear like on a regulat cd player.
But the audio has some filtering on it.

I have professionally recorded the console into my Audio Interface
then compared it to the new (07-01-2011) Xebra release.
Sounds exactly the same.

Cheers.

[drhycodan]

Great news indeed, now all that Xebra needs to achieve perfect PSX emulation is the Instruction Cache frequency of the PSX so we don't have to mess with the simulation model anymore.
Ok the sound is messed up in Xenogears, it was fine in 110105, but not the latest. Now how do I set it back like it was before?

[Ilya-v]

Check if N=0 (sound settings).

If not
Delete XEBRA.INI
And reset the settings.

[drhycodan]

I did delete the .ini to reset all the settings, but still no go.

[Ilya-v]

How the problem sounds like?
So I can explain it to Dr. Hell.

[drhycodan]

Just the sound effects like when you move the cursor or when you run into a save point. The sound is just messed up, I don't know how else to put it. Why not test Xenogears for yourself and see?

[Ilya-v]

i dont have it

[Kaan]

I can confirm xenogears sound problems. It's like there is no interpolation at all. Menu sound effect is too loud and too thin. (also noisy) I added an attachment as an example.

[Ilya-v]

ok, I've informed Dr. Hell about this issue.

Kaan, can you please record some more in-game sounds?
the 5 clicking sounds of the menu are not enough.

convert it to mp3 and then zip (it will be smaller).