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Amiga - native Paula sound

category: general [glöplog]
With KB on this one, just listen to some of the bad youtube recordings of amiga demos where they recorded it in full separation! Sounds worse than it did on the real thing!

anyway...

MONO!!
added on the 2013-10-01 14:11:15 by djh0ffman djh0ffman
Youtube has completely raped and crapped-on visuals because of incorrect frame rate, so complaining about stereo separation is a bit rediculous.
added on the 2013-10-01 14:46:23 by yzi yzi
I tried recordings with 30% separation, but as someone here pointed out, instruments like drums can suddenly switch from left to right and it can be very disconcerting, and the whole thing just sounds... wrong. No degree of separation is any good at all, certainly not 100%, so I'm sticking with my mono recordings.

I think it stems back from my original real Amiga days, when I only had mono cassette recorders and mono TV sound output to listen to it with, so I just got used to it. I think I ended up with about twenty mono tapes and just one stereo tape, and I found it jarring to listen to even then. Of course, blending the sides was impossible back then, unless I had VERY expensive equipment.

On a related note, does anyone remember something called the Sound Enhancer for Amigas? It was meant to bring out the quality of Paula sound, but it really ended up sounding bad a lot of the time. The filter didn't help much, either. It was a total waste of time, I think.
added on the 2013-10-01 22:02:09 by Foebane72 Foebane72
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@Foebane72: mp3's Joint Stereo is 100% stereo, it just stores data in different format than left/right (it's middle/side instead) but it still gives you 100% reproduction of stereo image.


Whoawhoa, hold your horses right there.

The point about the mid/side encoding is that the encoder can then allocate less bits to the side channel than to the mid one. That's mostly ok for usual stereo content, as many reproduction/radio systems use mid/side with disadvantages for the side channel and thus stereo music is usually mastered in a way that most of the stuff is going on in the middle of the field, but it's very likely to degrade quality on an amiga where L and R are actually two completely separate entities.

So if you want to encode MODs with 100% stereo separaion, always use full stereo.

It mostly depends on psychoacoustic model implemented in a given MP3 encoder, or rather how it distributes bits for stereo image reproduction - I wouldn't say that it depends on the way the stereo image is stored - L/R or M/S, they're both lossless in that aspect, in contrast to Intensity Stereo for example.
Also I think that you confuse MP3 Stereo with MP3 Dual Channels encoding methods. In Stereo mode there's still correlation between channels. In Dual Channels mode channels are encoded independently but then you get half the bits for actual sound reproduction which again may sound awful (good stereo reproduction but more pre-echo, ringing, smearing, and other compression artifacts).

I think that there should be no perceptible difference between Stereo & Joint Stereo encodes even in case of Amiga artificial sound, especially on high bitrates. Actually it is possible for Joint Stereo to sound better, but finding that out would need a real test, a blind one preferably.
added on the 2013-10-02 12:14:22 by rutra80 rutra80
AFAIR the filter related to Amiga LED was simply a lowpass filter.
added on the 2013-10-02 12:18:07 by rutra80 rutra80
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AFAIR the filter related to Amiga LED was simply a lowpass filter.


yep, but not only related to the filter

("The analog filters -- more complications" part)
https://bel.fi/alankila/modguide/interpolate.txt

and some practical tweaks for Paula

http://www.youtube.com/watch?v=PcN_iLGxEn8


Anyway... "In the days" i did just use a treble knob on amplifier set to the max. Added a little bass also and it worked fine. But to be honest - even SB Live! was lacking in high harmonics content so don't let the old Paula girl feel to bad.

As for stereo in 4 channel mods - usually musicians didn't care about it at all.
added on the 2013-10-02 16:07:37 by grogon grogon
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As for stereo in 4 channel mods - usually musicians didn't care about it at all.


So the stereo thing is superfluous? Very little practical use, and more a last-minute spec change? The only practical use I can think of is for sound sampling for use in games. No, hang on, that's not practical either.

And I didn't know that both sides were mixed if one socket were unplugged, so all those cables I bought to mix everything were unnecessary. D'oh!
added on the 2013-10-02 18:24:32 by Foebane72 Foebane72
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So the stereo thing is superfluous?


As a hardware feature it is useful - it allows to have real stereo if you stream stereo samples to channels accordingly. But when we talk about Protracker music, where you wanted to put as much sounds in as little space as possible - that's waste of kilobytes and polyphony.

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And I didn't know that both sides were mixed if one socket were unplugged, so all those cables I bought to mix everything were unnecessary. D'oh!


In A600/A1200 - yes (not sure what with A500+). A500 doesn't do that.
added on the 2013-10-02 18:43:15 by grogon grogon
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In A600/A1200 - yes (not sure what with A500+). A500 doesn't do that.


I had an A500 and then an A1200, so I guess since the former didn't have the mixing feature, I never thought to investigate it in the latter.
added on the 2013-10-02 22:59:06 by Foebane72 Foebane72
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So the stereo thing is superfluous?

Mind you, the chip wasn't designed with mod music in mind (which didn't really exist at this point). And there are enough MODs which carefully avoid instruments jumping around between left and right, so they sound perfectly okay in (reduced) stereo.
There are even MODs which try to create a stereo chorusing effect, for example by playing the same sound pitched or delayed by a slightly different amount on each speaker. Mixing such a tune mono-summed will sound wrong. There is just no single setting that will sound right with all MODs ever made. You may have to change the settings on a tune-by-tune basis.
added on the 2013-10-03 23:07:36 by yzi yzi
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There are even MODs which try to create a stereo chorusing effect, for example by playing the same sound pitched or delayed by a slightly different amount on each speaker. Mixing such a tune mono-summed will sound wrong. There is just no single setting that will sound right with all MODs ever made. You may have to change the settings on a tune-by-tune basis.


Sod that. Mono only.

At least Paula doesn't have the "noise-cancelling" effect that Pokey does on the A8 when exactly the same sound is played through two or more channels.
added on the 2013-10-04 01:25:45 by Foebane72 Foebane72
pokey having upper hand on paula lol! tell me more :)
added on the 2013-10-04 08:53:34 by Oswald Oswald
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pokey having upper hand on paula lol! tell me more :)


It's not an "upper hand" thing, more likely a disadvantage or a plain ol' fault.

I've heard it in Pokey tunes, and I've even replicated it myself: when two sound channels play exactly the same frequency and amplitude and waveform, a lot of the time it suddenly goes quiet, as if the two waveforms were eliminating each other because of the synchronisation. It's irritating to hear in music.

Paula is far superior in every way, of course! :D
added on the 2013-10-04 19:44:09 by Foebane72 Foebane72
From a sound engineering point of view, if you mono-sum everything, you make it harder to distinguish sounds. Spreading channels/tracks even very slightly can do wonders to clarity and being able to separate the sounds. As a rule of thumb you generally shouldn't place things at _exactly_ the same pan position. Pan everything slightly apart, it will make a better mix. (I've heard that there are people who insist on "true mono listening"... and they only have one physical loudspeaker of course, because you can't have true mono with more than one loudspeaker)
added on the 2013-10-04 20:01:30 by yzi yzi
I should also point out that Pokey only produces square waves (to my knowledge), and so it's even easier for the cancelling effect to take place.

I don't think it happens at all with SID.
added on the 2013-10-04 20:56:59 by Foebane72 Foebane72
Well, most Pokey stuff is unbearable to listen to, because they use the low-resolution more-polyphony mode where everything is horribly out of tune. If you can stand that crap, then you're tone-deaf and/or crazy to begin with, so who cares about frequency canceling.
added on the 2013-10-04 21:16:33 by yzi yzi
There are some people who are amazingly good at writing POKEY tunes, though (e.g. X-Ray) :)
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Well, most Pokey stuff is unbearable to listen to, because they use the low-resolution more-polyphony mode where everything is horribly out of tune. If you can stand that crap, then you're tone-deaf and/or crazy to begin with, so who cares about frequency canceling.


Your opinion. And please: define "tone-deaf".

I grew up with A8 audio and never even heard a SID until I heard SID sound simulated on my Amiga - to me, SID is an acquired taste, as whilst it can be melodic, there's so much synth noise to go around as well.

Plus, I love the funky sounds that A8 produces that SID can't - I think it's known as "Distortion 12" with Atari BASIC's SOUND command. What's more, the distinctive bass sound that A8 is known for is derived from that distortion, and the notes are perfect, what few of them they are.

I could be wrong, I don't quite know how "Distortion 12" is laid out. There are also sounds there that are "mechanical" or "metallic", and I think it's cool. I'd love to see SID do that.
added on the 2013-10-04 21:43:07 by Foebane72 Foebane72
It's not opinion, I recently looked into that, when Desire released their first A8-intro. I heard it was out of tune (okay, so perhaps not everyone can hear that, some people ARE tone-deaf), and was wondering why. Then I found that most A8-stuff sounds like that.
Looking at the tech specs of POKEY revealed that they only use an 8-bit value for the frequency divisor: http://en.wikipedia.org/wiki/POKEY#Audio_Channel_Frequency
So POKEY just has very limited resolution. SID uses 16-bit values, so it does not suffer this problem.
added on the 2013-10-04 23:38:34 by Scali Scali
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It's not opinion, I recently looked into that, when Desire released their first A8-intro. I heard it was out of tune (okay, so perhaps not everyone can hear that, some people ARE tone-deaf), and was wondering why. Then I found that most A8-stuff sounds like that.
Looking at the tech specs of POKEY revealed that they only use an 8-bit value for the frequency divisor: http://en.wikipedia.org/wiki/POKEY#Audio_Channel_Frequency
So POKEY just has very limited resolution. SID uses 16-bit values, so it does not suffer this problem.


But listen to the funky bass notes! Cool, eh? SID can't do that!

8-bit values? Who cares? Amiga sound is only 8-bit but it sounds awesome for the time. I fail to see what you're getting at.

SID may use 16-bit values, but you have to LIKE it. Don't you see? You can rant about SID being absolutely revolutionary for the time, but if you don't LIKE the sound, then that's all irrelevant.

And besides, Pokey could do 16-bit too, it would only tie up two channels for the extra precision. And since Pokey already has one more channel than SID, then I consider that a bonus.

Look, don't get all high and mighty with me about trashing Pokey in favour of SID as being the better 8-bit sound chip - all I know is I like the sound of Pokey much more, warts, imperfections and all.

And you can't sway me on that. Warhawk on C64 rather than A8? I find the opening piercing wail far more annoying. A8 just gets down to the main tune.
added on the 2013-10-05 00:26:52 by Foebane72 Foebane72
This one here?: http://www.youtube.com/watch?v=ED_Qi0WTnSo

LMAO yeah there's no way the SID could pull off that bass... :D

No one just does because you can get a much richer and better bass sounds from it too.

But limitations can lead to aesthetics that people end up liking. So keep on keeping on and the blipping a blopping.
One last thing: I fail to see how comparing a 1979 sound chip to a 1982 sound chip is even remotely fair. After all, progress is part of the microcomputing world, and what comes later will always be superior in some way or another.

Just leave us Pokey fans alone, and let us appreciate the chip on its own merits, without comparison with others, especially later ones.
added on the 2013-10-05 00:43:17 by Foebane72 Foebane72
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I fail to see what you're getting at.


Apparently. I was getting at the resolution of the frequency divisor. Amiga plays 8-bit samples, but it has more than 8-bit resolution to control the frequency, as does the C64.
Which is why they don't sound as out-of-tune as POKEY.

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SID may use 16-bit values, but you have to LIKE it. Don't you see?


That wasn't the point I was making. I was just pointing out that POKEY has some technical limitations that prevent it from playing every note in tune in most modes. Which results in many POKEY songs sounding out-of-tune.
That is a fact, not an opinion. I don't want to get into a debate of which chip sounds better or whatever. I don't care.
added on the 2013-10-05 10:57:36 by Scali Scali
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8-bit values? Who cares? Amiga sound is only 8-bit but it sounds awesome for the time. I fail to see what you're getting at.

Way to miss the point, dude.

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(what Scali said)

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