Audio vs Amiga

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Re: Audio vs Amiga

Postby Stefan jL » Mon Apr 09, 2012 9:22 pm

galahad wrote:
Whether it be mod or proper chip music, the Amiga had most machines beat. Amiga sound was not distorted nor was the clarity bad.


I think what he ment with the clarity is that some (all?) Amiga 500/1000 had a capacitor that filtered the sound output, i am sure i read somewhere that a common mod was to remove the filter capacitors in Amiga.
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Re: Audio vs Amiga

Postby FedePede04 » Mon Apr 09, 2012 9:46 pm

galahad wrote:
FedePede04 wrote:personally i don't think the Amiga was better, all my friends had and made music on the Amiga, i also made a few scores.
i think that the Amiga sound output was to distorted and the sound clarity was to poor, and it is even worse if you hear it today,
because the sampling sound is so good today.
if you hear the ym-sound today it will still sound clean.

where i think the Amiga was superior to the Atari was graphic.

if you take the spec of the YM, when it is properly one of the most simple sound-chip, use in a computer, (but where was a lot that use it)
where the C64 sound chip was properly one of the best synth chip ever use in a computer. even today, it is very difficult to emulate, because of it's analog filters, and if you wanted something extraordinaire out of the YM, when you need a lot of CPU power.

I would have preferred that they had use a diffident sound chip in the ST, but i will take the ST-sound over the Amiga any day.


is this post serious? i'm not going to start ST bashing, but clearly the Amiga you heard was knackered.

Whether it be mod or proper chip music, the Amiga had most machines beat. Amiga sound was not distorted nor was the clarity bad.

Was the Amiga you heard playing under water? :roll:


and this is not to do any Amiga bashing either. i could not care less about one computer brand or an other computer brand.

I think it's a a taste of matter, i have always love chipmusic sins i hear the first on the C64 and the MSX way back around 1983-1985.
i just love the sound of the synth sound.

but if you take the samples sound of the Amiga when using it for music i had a maximun sample frequency of around 29 khz, but that was the hightest note, so if you took that an octav down you have one of 15 khz, so i you had 3 octav you would end with a sample freq from around 3 khz to 29khz, try sample somthing on you pc at around 15 khz and it will also sound muddy and not clean.

the maxium frequency of the atari was around 130khz, plus it was a clean wave form there for it will alway sound much cleaner.

to give you an example the Xenon 1, the lead guitar it sound like crap in my opion, and it was not only in that game, i could point to many games the the instrument sounded like crap.

one thing the Amiga did bring the useable samples to the home-computers, and that was great, but i did not like the sound of it and still don't.
as I said i will take chip-sound over the Amiga any day, i just like the sound better.

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Re: Audio vs Amiga

Postby galvatron1983 » Mon Apr 09, 2012 9:50 pm

FedePede04 wrote:
galahad wrote:
FedePede04 wrote:personally i don't think the Amiga was better, all my friends had and made music on the Amiga, i also made a few scores.
i think that the Amiga sound output was to distorted and the sound clarity was to poor, and it is even worse if you hear it today,
because the sampling sound is so good today.
if you hear the ym-sound today it will still sound clean.

where i think the Amiga was superior to the Atari was graphic.

if you take the spec of the YM, when it is properly one of the most simple sound-chip, use in a computer, (but where was a lot that use it)
where the C64 sound chip was properly one of the best synth chip ever use in a computer. even today, it is very difficult to emulate, because of it's analog filters, and if you wanted something extraordinaire out of the YM, when you need a lot of CPU power.

I would have preferred that they had use a diffident sound chip in the ST, but i will take the ST-sound over the Amiga any day.


is this post serious? i'm not going to start ST bashing, but clearly the Amiga you heard was knackered.

Whether it be mod or proper chip music, the Amiga had most machines beat. Amiga sound was not distorted nor was the clarity bad.

Was the Amiga you heard playing under water? :roll:


and this is not to do any Amiga bashing either. i could not care less about one computer brand or an other computer brand.

I think it's a a taste of matter, i have always love chipmusic sins i hear the first on the C64 and the MSX way back around 1983-1985.
i just love the sound of the synth sound.

but if you take the samples sound of the Amiga when using it for music i had a maximun sample frequency of around 29 khz, but that was the hightest note, so if you took that an octav down you have one of 15 khz, so i you had 3 octav you would end with a sample freq from around 3 khz to 29khz, try sample somthing on you pc at around 15 khz and it will also sound muddy and not clean.

the maxium frequency of the atari was around 130khz, plus it was a clean wave form there for it will alway sound much cleaner.

to give you an example the Xenon 1, the lead guitar it sound like crap in my opion, and it was not only in that game, i could point to many games the the instrument sounded like crap.

one thing the Amiga did bring the useable samples to the home-computers, and that was great, but i did not like the sound of it and still don't.
as I said i will take chip-sound over the Amiga any day, i just like the sound better.

/Peter


From a completely non-technical viewpoint, I just think the Amiga music sounds nicer! Closer to what real-life instruments sound like when brought together to create a soundtrack I guess...
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Re: Audio vs Amiga

Postby FedePede04 » Mon Apr 09, 2012 9:58 pm

Stefan jL wrote:
galahad wrote:
Whether it be mod or proper chip music, the Amiga had most machines beat. Amiga sound was not distorted nor was the clarity bad.


I think what he ment with the clarity is that some (all?) Amiga 500/1000 had a capacitor that filtered the sound output, i am sure i read somewhere that a common mod was to remove the filter capacitors in Amiga.


no it was not the low-pass filter. i remember talking with my friends back when, and i was saying same thing, my friends say, just wait to you hear it with the low pass-filter off. it improve it, but not much, the problem with the Amiga is the sampling frequency is to low.

on big thing the Amiga had over the Atari was the 4 channel, for me the perfect sound chip for the atari would have been the Philips Saa1099 but you can win the all.

and just to show that there was nothing wrong with that Amigas that i heard.

Here is a link to some music, that one of my friend did on the Amiga.
http://www.youtube.com/watch?v=F7u0RMkQ ... plpp_video
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Re: Audio vs Amiga

Postby Stefan jL » Mon Apr 09, 2012 10:06 pm

FedePede04 wrote:, the problem with the Amiga is the sampling frequency is to low.



Thats the problem the ST also has :D
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Re: Audio vs Amiga

Postby FedePede04 » Mon Apr 09, 2012 10:08 pm

galvatron1983 wrote:From a completely non-technical viewpoint, I just think the Amiga music sounds nicer! Closer to what real-life instruments sound like when brought together to create a soundtrack I guess...


like i said we like what we like :)

but you said that you only had Amiga before,
when i think you should try listen to this guy, i think he is one of the greatest ST composer.

http://chipmusic.org/ultrasyd/music/atari-sucks
http://www.youtube.com/watch?v=l0ap_PG6 ... wMcAFhQ%3D
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Re: Audio vs Amiga

Postby FedePede04 » Mon Apr 09, 2012 10:11 pm

Stefan jL wrote:
FedePede04 wrote:, the problem with the Amiga is the sampling frequency is to low.



Thats the problem the ST also has :D


yes you are 100% right, and it is even worse, it also have a much lower sampling resolutions, by defualt. :lol:
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Re: Audio vs Amiga

Postby darklight » Mon Apr 09, 2012 10:44 pm

Some of you guys are comparing apples with oranges, and arguing on this subject really is futile. There are two issues here:

- Amiga has ST beat when playing sample based .MOD files. Most (I presume?) Amiga games had MOD soundtracks, with samples played at a higher frequency than an ST was capable of doing. The Amiga hardware was built to do this. STs, not so. There can be no argument about this.

- What is better chip tune or MOD format? Most of the STs soundtracks were chip tunes. These sound much clearer than .MODs because they are pure sine / square waves (and noise). MODs do sound muffled (to varying degrees) because even the Amiga was not capable of playing the higher frequency samples neccessary for crystal clear sound. I belive Amiga also did chip tunes too, but these I think were less common, and I cant comment on wether Amiga was technically superior in this regard (although I'd guess it was?)

Wether you prefer MOD samples or pure chip tune waveforms is personal preference - no one can ever win an argument about this. Personally, I believe a lot of Amiga MODs now sound quite dated, flooded with bad early 90s dance music samples. I much prefer the soundtrack to Blood Money on the ST, mainly due to this fact.
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Re: Audio vs Amiga

Postby wongck » Mon Apr 09, 2012 11:10 pm

darklight wrote:Wether you prefer MOD samples or pure chip tune waveforms is personal preference - no one can ever win an argument about this.


yeap, totally agree.
I think mod samples sounds more like mp3 as they are nearer to the music you hear on the radio, whereas you cannot mistaken the chip tune music of a game machine.
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Re: Audio vs Amiga

Postby mc6809e » Tue Apr 10, 2012 3:48 am

Stefan jL wrote:
galahad wrote:
Whether it be mod or proper chip music, the Amiga had most machines beat. Amiga sound was not distorted nor was the clarity bad.


I think what he ment with the clarity is that some (all?) Amiga 500/1000 had a capacitor that filtered the sound output, i am sure i read somewhere that a common mod was to remove the filter capacitors in Amiga.


Everything after the A1000 had a hardware register that would turn the filter on and off.

Turning it off was like taking cotton out of one's ears.

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Re: Audio vs Amiga

Postby mc6809e » Tue Apr 10, 2012 5:11 am

FedePede04 wrote:the problem with the Amiga is the sampling frequency is to low.



The sample playback rate can be limited by the maximum DMA rate, but the audio DACs don't have to be DMA driven. The audio hardware on the Amiga can be setup so that any of the four channels can generate an interrupt whenever that channel needs a new sample, making higher rates possible. One reasonable setup is using DMA to drive three DACs and the CPU to drive the fourth. The DMA driven DACs can play non-percussive instruments while the CPU can handle cymbals and the like where the production of higher frequencies is important. It's even possible to add more voices this way by using the CPU to mix samples from multiple sources.

Another possibility is to use the COPPER to load some of the audio DACs directly. Using six COPPER instructions per scanline (three moves and three waits) gives a sampling rate of 47KHz. As above, one can use DMA for for non-percussive sounds and COPPER lists for "crash" type sounds.

But mostly no one bothers with any of this because it usually makes little difference and isn't worth the trouble. Turning off the audio filter allows all sorts of higher-order harmonics to fill the frequencies above 14.5KHz making most sounds brighter. The introduction of these harmonics isn't usually a problem. We're not always trying to perfectly reproduce a sound. We're generating sound. When playing back a two-sample square wave, for example, we WANT all those extra harmonics to be present.

Like I said, though, if you really want a sampling rate above 29KHz, there are alternatives.

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Re: Audio vs Amiga

Postby Cyprian » Tue Apr 10, 2012 10:08 am

mc6809e wrote:Another possibility is to use the COPPER to load some of the audio DACs directly. Using six COPPER instructions per scanline (three moves and three waits) gives a sampling rate of 47KHz. As above, one can use DMA for for non-percussive sounds and COPPER lists for "crash" type sounds.

really nice trick, good to know that COPPER can write DAC registers,
btw it works if only ECS/OCS doesn't steal COPPERs meory cycles (e.g 6 bitplanes mode)
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Re: Audio vs Amiga

Postby mc6809e » Tue Apr 10, 2012 4:37 pm

Cyprian_K wrote:
mc6809e wrote:Another possibility is to use the COPPER to load some of the audio DACs directly. Using six COPPER instructions per scanline (three moves and three waits) gives a sampling rate of 47KHz. As above, one can use DMA for for non-percussive sounds and COPPER lists for "crash" type sounds.

really nice trick, good to know that COPPER can write DAC registers,
btw it works if only ECS/OCS doesn't steal COPPERs meory cycles (e.g 6 bitplanes mode)


There are 72 DMA slots/scanline for the COPPER to use when 6 bit planes are turned on. One probably wants them evenly spaced out, though, so 56 would be available for COPPER instructions. Three moves and three waits would take only 15 of those so it's possible to get one 47KHz voice this way. For four voices, the move instructions can be grouped using only 33 DMA slots.

Of course the extra bit planes and COPPER operations block CPU access to memory and this slows things down quite a bit assuming there's no fast ram in the system.

For a 200 scan line display area, there are 112 even memory cycles available minus 40 for the extra planes minus 33 for the COPPER leaving 39 cycles for the CPU. Pretty bad. For the 62 remaining blank scanlines, the CPU can access odd cycles, so the 33 COPPER cycles don't block.

So in the worst case, assuming an instruction stream dominated by chipram memory accesses (pretty common), the CPU runs at about 50% speed.

Things look much better using an 8-color 3 bit plane background and 16 color sprites. You get 24 colors per scan line and the CPU can access the odd memory cycles freed up by using fewer bit planes.

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Re: Audio vs Amiga

Postby FedePede04 » Tue Apr 10, 2012 6:08 pm

mc6809e wrote:
FedePede04 wrote:the problem with the Amiga is the sampling frequency is to low.



The sample playback rate can be limited by the maximum DMA rate, but the audio DACs don't have to be DMA driven. The audio hardware on the Amiga can be setup so that any of the four channels can generate an interrupt whenever that channel needs a new sample, making higher rates possible. One reasonable setup is using DMA to drive three DACs and the CPU to drive the fourth. The DMA driven DACs can play non-percussive instruments while the CPU can handle cymbals and the like where the production of higher frequencies is important. It's even possible to add more voices this way by using the CPU to mix samples from multiple sources.

Another possibility is to use the COPPER to load some of the audio DACs directly. Using six COPPER instructions per scanline (three moves and three waits) gives a sampling rate of 47KHz. As above, one can use DMA for for non-percussive sounds and COPPER lists for "crash" type sounds.

But mostly no one bothers with any of this because it usually makes little difference and isn't worth the trouble. Turning off the audio filter allows all sorts of higher-order harmonics to fill the frequencies above 14.5KHz making most sounds brighter. The introduction of these harmonics isn't usually a problem. We're not always trying to perfectly reproduce a sound. We're generating sound. When playing back a two-sample square wave, for example, we WANT all those extra harmonics to be present.

Like I said, though, if you really want a sampling rate above 29KHz, there are alternatives.


Hi mc6809e

i have never heard any thing play in the way you describe, so i can't comment about it.

at the time my friends programmed for the Amiga the thing du describe was not common knowledge, it could be interesting to hear what the Amiga could sound like :)
the only thing i remember about the sound chip on the Amiga was the you could get it to play in two different modes "one Shot" and "loop"
but at the time that we had Atari and Amiga did i never heard any sound/music played the way you described. so the picture of the Amiga sound that i have i my mind is the unclear and muddy sound, properly the same way, as many Ex Amiga user have there recollection of the Atari St sound. we tend not to follow the development when it is dead long ago, so we keep ours recollection of what we heard many years ago.

so if you have a short mp3. of the Amiga playing in 47khz then i would be very interested to hear that.

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Re: Audio vs Amiga

Postby Shredder11 » Wed Apr 11, 2012 10:34 pm

Well for me and my musician background, my STE was great due to the MIDI ports allowing me to hook up the best sounding gear available ;) The Amiga seemed to lack the MIDI ports I hear :mrgreen: :lol:

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Re: Audio vs Amiga

Postby Frank B » Thu Apr 12, 2012 5:42 am

Shredder11 wrote:Well for me and my musician background, my STE was great due to the MIDI ports allowing me to hook up the best sounding gear available ;) The Amiga seemed to lack the MIDI ports I hear :mrgreen: :lol:


Paula was great but these days I prefer SID voice ST chip tunes. The stuff from Cream is marvellous!

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Re: Audio vs Amiga

Postby Shredder11 » Thu Apr 12, 2012 7:29 pm

With the Amiga I always knew it had superior audio hardware, but somehow I never took to it. If the Amiga sound could be described by a colour, it would be beige. Solid, competent, smooth but somehow dull. Am I being harsh? I do not mean to be but with 1980s computer audio, I always prefered something with a bit more bite rather than Hi-Fi perfect. The Atari STE was somewhere between beige and bite! :lol:

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Re: Audio vs Amiga

Postby mc6809e » Thu Apr 12, 2012 9:26 pm

Shredder11 wrote:With the Amiga I always knew it had superior audio hardware, but somehow I never took to it. If the Amiga sound could be described by a colour, it would be beige. Solid, competent, smooth but somehow dull. Am I being harsh? I do not mean to be but with 1980s computer audio, I always prefered something with a bit more bite rather than Hi-Fi perfect. The Atari STE was somewhere between beige and bite! :lol:


It was that damned audio filter. Easy to fix, but there was no need for it. Some engineer really didn't understand what he was doing.

It's important to filter a source BEFORE it's sampled to reduce aliasing, but once it's sampled, there's really little need for filtering the output. An 8 bit sample resolution is usually enough to limit the harmonics introduced as one sample is replaced with another at the DAC as the sample is output.

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Re: Audio vs Amiga

Postby nativ » Thu Apr 12, 2012 9:29 pm

The STe's tracking capabilities are quite impressive and you still have Midi and YM!

The amount of storage for 16 bit samples it wouldn't have been worth adding that hardware although it was available as the Replay 16
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Re: Audio vs Amiga

Postby galvatron1983 » Thu Apr 12, 2012 10:49 pm

Again looking at it from a non technical viewpoint, I just prefer how the "real life instrument" style of audio sounds, compared the chip tune style.

Sure a sampled segment of music might sound scratchy and low-res on an Amiga, but to me it still sounds better then the ST....
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Re: Audio vs Amiga

Postby Xerus » Fri Apr 13, 2012 12:44 am

I like both (chip & samples) and that is why the Falcon is the ideal machine for me :)

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Re: Audio vs Amiga

Postby Zamuel_a » Sun Apr 22, 2012 3:47 pm

One thing I wonder about when you compare the sound between Amiga and an STE is how much processor power each of them take if you compare them to each other. I know the Amiga won't take much power to play a 4ch mod but the Amiga is 10% slower than an Atari so if you make a mod player on an STE that can play a mod in 10% processor power, when you would more or less get the same performance. Also I guess the Amiga need to load samples and stuff from chip RAM, which might lower the processor power alittle bit more.
Had been interessting to see a comparison between an Amiga and STE in how much time you have left. Maybe an STE can play a MOD with the same time left as you would get on an Amiga.
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Re: Audio vs Amiga

Postby Avanze » Sun Apr 22, 2012 10:30 pm

It is my opinion that the Yamaha (YM2149) induces greater creativity on the part of the composer, or it has that inherent potential within from the mere simplistic to the more complex ingenuity of sound. An impressive array on hand such as the SID-voice, sync-buzzer, and processed digital effects. I believe there is more flexibility and room for further exploration of available sounds by sheer means of producing its tight waveform patterns. In this field the composer Tao really excels. Conversely, the Paula chip is just a simple way to playback samples. That is not a fault on its part – it was designed to do just that and so it works wonderfully. I wonder how many Commodore 64 users prefer the Yamaha chip too. As a comparison between two 'similar' sounding chips.

Overlooking all the technical details between the two chips now. I have a question for you: How often do you listen to the Yamaha or Paula?

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Re: Audio vs Amiga

Postby mc6809e » Mon Apr 23, 2012 8:37 pm

Zamuel_a wrote:O I know the Amiga won't take much power to play a 4ch mod but the Amiga is 10% slower than an Atari so if you make a mod player on an STE that can play a mod in 10% processor power, when you would more or less get the same performance. Also I guess the Amiga need to load samples and stuff from chip RAM, which might lower the processor power alittle bit more.
Had been interessting to see a comparison between an Amiga and STE in how much time you have left. Maybe an STE can play a MOD with the same time left as you would get on an Amiga.


On the STE you basically have two buffers that output audio samples at a few fixed rates. This means waveforms must resampled and mixed by the CPU for each pitch value before being written into the audio buffer before output. This can take a lot of CPU time. There's a thread somewhere with some of the details.

On the Amiga, audio mixing and resampling are done in hardware. The CPU is only responsible for selecting a waveform and its length, the pitch, and the volume. The hardware even has the option of volume or pitch modulating one waveform with another chiptune style, though this is rarely used. Each of the four channels takes a maximum of one DMA slot per scanline (of 226 available). And because the fetch is performed on an odd memory cycle, it's nearly always invisible to the CPU.

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Re: Audio vs Amiga

Postby Zamuel_a » Tue Apr 24, 2012 7:47 pm

Yes I know that the STE is much slower at playing mods compared to an Amiga, but that's not my question. I wonder if the speed LEFT after you play a mod aren't so different. The Amiga runs at 7.09Mhz and the STE at 8, that's a 13% difference so if you make a mod player on atari that run's at 13% the speed left for other stuff would be the same on atari and the amiga. Maybe a mod player at 13% is abit optimistic, but let's say a 25khz player at 20% must be possible? (The 50khz lance tracker runs at 30%).
Also one thing I came up with once then I was thinking about mod playing is that isn't it much faster if the player runs 7bit samples instead of 8bit? You don't need to compare each sample you add if they are higher than 255. Instead you just add them and don't have to do anything else. Doing a 7 bit mod player at 25khz must be possible then at arount 15% and then you get the same time left as the amiga.
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