boomlinde
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Sweden
TSC wrote:

and the other filter removes all the high end for some ridiculous reason.

I see, that makes sense. I mostly ever used A1200s, so I never noticed. I think the filters were a half-assed attempt at simple reconstruction filters. The niftiest use I found of them was for the tunnels in Lotus Espirit Turbo Challenge II -- when you ride into tunnels the filter is enabled smile

Funny thing is that when people hear "filter" they get all excited assuming it's a variable cutoff frequency resonant 12/24 dB/octave low pass filter. The roll-off starts somewhere at, what, 10 KHz, with a kind of flat roll-off (6 dB/octave?). It's really boring.

boomlinde
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Sweden
yogi wrote:

Isn't that what made the Amiga great, it was the first sampler?

There were a few home computer sound chips built to facilitate sample playback at the time Amiga was released.

Got totally away from the concept of a sound chip, it sounded like what ever you feed it?

Well, it is a sound chip (but it has a few other features totally unrelated to sound). To be fair, the Paula behaved a lot like PSG sound chips of the time. Beyond setting up sample pointers and playback lengths, it's a lot like a PSG in that you typically produce music by changing the period length of each channel.

The home computer sound device that best embodies the idea of "sounding like whatever you feed it" is probably something like the Covox Speech Thing or a beeper. You literally push samples to it at whatever rate you want/can, and it outputs them on its resistor ladder without any fuzz.

After people were making the amazing mod music that DIDN'T sound like a chip, people started figuring out how to play samples on the ST's AY?

The Amiga was released at almost the same time as the ST and didn't sound quite like it right at the start. But people had already been using tricks to play samples back on at least SID chips, but probably all kinds of beepers and PSGs.

Never had hands on an Amiga, so does it have a a unique sound, aside from the filters?

Well, you can quite easily replicate it. The software and sample sources are probably more important aspects of its perceived uniqueness. The least trivial aspect of emulating the Paula is probably getting the variable rate playback to sound good. Simple interpolation will just sound awful, so you have to do either ovesampling+filtering+downsampling or synthesize it with something like BLITs.

4mat
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you'll be wanting the magic amiga doc

yogi
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Jelly Stone park, MD USA
boomlinde wrote:

There were a few home computer sound chips built to facilitate sample playback at the time Amiga was released.

This is interesting. I know that a noise channel was included on most sound generators at that time but I didn't think that sample play back was by design, but more for enhancement of the tone channels.

Well, it is a sound chip (but it has a few other features totally unrelated to sound). To be fair, the Paula behaved a lot like PSG sound chips of the time. Beyond setting up sample pointers and playback lengths, it's a lot like a PSG in that you typically produce music by changing the period length of each channel.

The home computer sound device that best embodies the idea of "sounding like whatever you feed it" is probably something like the Covox Speech Thing or a beeper. You literally push samples to it at whatever rate you want/can, and it outputs them on its resistor ladder without any fuzz.

When you say 'like a PSG', did/does it generate channels of digital waveforms or are you referring to shifting the pitch of a sample, as most wavetable synths do?
As to the Covox, when it was introduced on the Apple]['s MockingBoard,  seemed like a response to the Amiga and it's Paula.

The Amiga was released at almost the same time as the ST and didn't sound quite like it right at the start. But people had already been using tricks to play samples back on at least SID chips, but probably all kinds of beepers and PSGs.

Yes, these known tricks were rolled into the Palua by design. Where as the AY could be pushed to do samples, at a high cost of CPU cycles,  but it's main application was generating waveforms.
The development history of the two machines is a good soap opera, full of twists and  tangles. From my reads, seemed like the Amiga was designed for the Paula, when the original customer, Atari, dropped support for the sound chip.

....The software and sample sources are probably more important aspects of its perceived uniqueness.

So true. IMO the Paula set the stage for digital sound. And at the same time it's revolutionary approach limits it's attraction for a stand-alone 'chip' synth. The Amiga has far more appeal as a whole system, from a retro aspect smile
Yogi

boomlinde
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Sweden
yogi wrote:

This is interesting. I know that a noise channel was included on most sound generators at that time but I didn't think that sample play back was by design, but more for enhancement of the tone channels.

First and only thing that springs to mind is the NES, but hopefully someone else can fill me in on other machines. I thought about PC-88 at first but I don't think those had sample decoding YM chips until years later.

yogi wrote:

When you say 'like a PSG', did/does it generate channels of digital waveforms or are you referring to shifting the pitch of a sample, as most wavetable synths do?
As to the Covox, when it was introduced on the Apple]['s MockingBoard,  seemed like a response to the Amiga and it's Paula.

Yeah, I mean more like a wavetable synth, but without resampling or anything like that. Just independent channel playback rates quite immediately derived from the master clock, like the channels of an YM2149 or the likes; a very simple design compared to most wavetable synthesizers, I think. When I think about "wavetable synthesizers" I think of the likes of MT32, AWE etc., though.

I didn't know about the Covox for Apple II!

Yes, these known tricks were rolled into the Palua by design. Where as the AY could be pushed to do samples, at a high cost of CPU cycles,  but it's main application was generating waveforms.
The development history of the two machines is a good soap opera, full of twists and  tangles. From my reads, seemed like the Amiga was designed for the Paula, when the original customer, Atari, dropped support for the sound chip.

It seems like a mess. Atari at the time were obiously interested in saving money by doing the simplest viable design. In the end, the ST is a pretty neat computer. I've been thinking that the Amiga could really have used a supporting off-the-shelf audio chip. Any YM would have made it a lot more than it was. Instead we have games where you have to choose either sound effects or music in the options menu or really annoying channel stealing, which seems quite ridiculous by the time they released the A1200. What if they just tacked on a PSG or an FM chip as well?

So true. IMO the Paula set the stage for digital sound. And at the same time it's revolutionary approach limits it's attraction for a stand-alone 'chip' synth. The Amiga has far more appeal as a whole system, from a retro aspect smile
Yogi

Agreed, agreed and agreed!

boomlinde
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Sweden
4mat wrote:

you'll be wanting the magic amiga doc

Great! I thought the Paula output was resistor ladders for sure.

yogi
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Jelly Stone park, MD USA

@4mat  Thanks also for the MAmiga doc. Very good info there, even though allot of the DSP clipped the top of my head wink
@broomlinde I hadn't considered the NES/Famicom but the DCPM was intended for samples indeed. Of course with the Japanese release date of '83 it pre dates the Amiga.
Did some fact checking on myself: the mocking board had a AY 3-8910 for the first ver, but later options included 'Speech'. But this was based on the SC-01 Vortrax chip. On the other hand, the later Covox Speech Thing was only PC and  was an R-2R DAC.

When I think about "wavetable synthesizers" I think of the likes of MT32, AWE etc., though.

smile smile I'm the other way round, thinking of the MT-32 and later GM Midi as a subset of wavetable. smile So much of the current soft synths are wavetable/sample based. the lines are blurred.
Yogi

maniacfreakquency
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Mexico

Thanks for all your answers guys. Maybe It would be better to fix the Amiga, the problems are in the keyboard and the floppy drive.