spookt Posted January 10, 2009 Share Posted January 10, 2009 Working now Nice tune too. Quote Link to comment Share on other sites More sharing options...
Tezz Posted January 10, 2009 Share Posted January 10, 2009 who knows maybe we can do editor for this kind of music.That'd be very cool. It's definately worth pursuing GTIA sound further. Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 10, 2009 Share Posted January 10, 2009 please, i know that pokey/ay/sid are better sound chip than GTIA but in this topic we are play on GTIA. ok. next zx spectrum music is from TDM, plays on 3 channels, attack, decay, volume control, no samples!: http://atari.pl/follininsane.mp3 (new) play on GTIA compare this to: http://atari.pl/tim.mp3 and http://atari.pl/follincore.mp3 if you find in internet another follins tune (or on follin play routine tune) take a link. who knows maybe we can do editor for this kind of music. that sounds cool... so in theory there are still all 4 channels of pokey left? how much cpu? Quote Link to comment Share on other sites More sharing options...
atariksi Posted January 10, 2009 Share Posted January 10, 2009 I remember there was a drums demo on Atari 8-bit that played different drums in a beat with screen on and it sounded like drums were sampled audio (like Sonix does on Amiga) rather than POKEY generated music. Drums is no problem. With 3kHz sampling you get the main frequency plus the harmonics. In some demos you have drums played by the VBI and it was clear enough. You can also use Pokey's generators, but 50Hz VBI is a bit slow for it. To the topic: No Problem with using GTIA for samples. Why not using this feature for drums , leaving the 4 channels of Pokey for "doing everything".... If you give an example of drums on POKEY w/o samples, perhaps someone can convert it to GTIA version... Quote Link to comment Share on other sites More sharing options...
Tezz Posted January 10, 2009 Share Posted January 10, 2009 It would be great if it's possible to add some GTIA sound as a 5th channel to the 4 ch Pokey tracks. Even for simple clicks it would be useful for rhythm etc. I've never touched anything with the GTIA sound myself so I'm unaware of how taxing it is. It could be the base for some great new title screen music if it's possible. I'd definately get into that. Quote Link to comment Share on other sites More sharing options...
peteym5 Posted January 11, 2009 Share Posted January 11, 2009 I have consider the ideal of using the GTIA sound for a 5th channel myself for simple sound effects, like explosions, gun shots, or anything that is not a pure tone. RMT music tracks can be 4 channels and does not leave anything for game sound effects. Usually we have to set a channel aside just for sound effects, having the GTIA channel is a viable option. Something I have always wondered about is how often do you need to write to this register. If its only a few times during a VBI, then it should not be a problem. Quote Link to comment Share on other sites More sharing options...
Rybags Posted January 11, 2009 Share Posted January 11, 2009 It's a case of even more often than for doing Pokey digital sound. As you'd probably have experienced, 4 KHz is about the acceptable minimum to plug direct volume values into Pokey if you're doing 4 bit sound. CONSOL is only 1 bit sound, and doing PWM effects is extremely CPU intensive. I've also tried just doing 1 bit sound, ie just treat values >8 as 1 and <8 as 0, but you're probably looking at one store per scanline for any sort of quality there. Depends on the effect you're after too - if it's just some sort of low pitched hum you're after, you could probably get away with a couple of dozen stores per frame. Quote Link to comment Share on other sites More sharing options...
xxl Posted January 11, 2009 Author Share Posted January 11, 2009 my very early version of jetboy has sound efect play on gtia - http://atari.pl/jettest.obx - change .obx to .xex (plays good only on real atari). music from zx game? sure: http://atari.pl/cybernoid.xex Quote Link to comment Share on other sites More sharing options...
Tezz Posted January 11, 2009 Share Posted January 11, 2009 (edited) my very early version of jetboy has sound efect play on gtiaThat was really neat emuating the original zx sound with the earlier conversion. I guess you decided to drop the GTIA sounds when you moved on to revamp Jetpac to it's final release version with Pokey RMT music. Edited January 11, 2009 by Tezz Quote Link to comment Share on other sites More sharing options...
Tezz Posted January 11, 2009 Share Posted January 11, 2009 It's a case of even more often than for doing Pokey digital sound. As you'd probably have experienced, 4 KHz is about the acceptable minimum to plug direct volume values into Pokey if you're doing 4 bit sound. CONSOL is only 1 bit sound, and doing PWM effects is extremely CPU intensive. Thanks for the info, I suspected that might be the case when I was thinking about itDepends on the effect you're after too - if it's just some sort of low pitched hum you're after, you could probably get away with a couple of dozen stores per frame.I think any use of the extra channel for sfx in a way that's viable without too many cycles used is good, perhaps it could be put to nice use in some game situations with some creativity. It'd sure be nice as mentioned above to have sfx (even v simple) not interupting the 4 ch pokey. Quote Link to comment Share on other sites More sharing options...
Kaz atarionline.pl Posted January 11, 2009 Share Posted January 11, 2009 I guess you decided to drop the GTIA sounds when you moved on to revamp Jetpac to it's final release version with Pokey RMT music. There is no final version yet (from my point of view ). Quote Link to comment Share on other sites More sharing options...
atariksi Posted January 11, 2009 Share Posted January 11, 2009 It's a case of even more often than for doing Pokey digital sound. As you'd probably have experienced, 4 KHz is about the acceptable minimum to plug direct volume values into Pokey if you're doing 4 bit sound. CONSOL is only 1 bit sound, and doing PWM effects is extremely CPU intensive. I've also tried just doing 1 bit sound, ie just treat values >8 as 1 and <8 as 0, but you're probably looking at one store per scanline for any sort of quality there. Depends on the effect you're after too - if it's just some sort of low pitched hum you're after, you could probably get away with a couple of dozen stores per frame. PCs did all sorts of music with 1-bit sound; digitized samples are CPU intensive but music notes should work okay. Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 11, 2009 Share Posted January 11, 2009 is the mentioned sample dithering similar to the GTIA sound? http://www.ffd2.com/fridge/chacking/c=hacking11.txt Quote Link to comment Share on other sites More sharing options...
xxl Posted January 11, 2009 Author Share Posted January 11, 2009 (edited) no! pokey/sid/ay have volume levels and you can play samples eg. 15,14,15,14... you got somting 14.5... but gtia have 1bit so: 1,0,1,0 - 0,5 ? heh no... on powerfull cpu with 1-bit you can generate multichannels with any wave: Edited January 11, 2009 by xxl Quote Link to comment Share on other sites More sharing options...
atariksi Posted January 11, 2009 Share Posted January 11, 2009 is the mentioned sample dithering similar to the GTIA sound? http://www.ffd2.com/fridge/chacking/c=hacking11.txt It's not as good as a 100% accurate DAC but the faster you can modify the bits in the DAC port, the better the simulation of higher bit depth. It also depends on how circuitry for the speaker out is constructed how many intermediate levels can be simulated. Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 11, 2009 Share Posted January 11, 2009 still not get it... where can i find some information? I mean not high level physic stuff but newbie info... Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 11, 2009 Share Posted January 11, 2009 http://omino.com/blog/2007/the-1-bit-dac/ Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 11, 2009 Share Posted January 11, 2009 http://arstechnica.com/articles/paedia/aud...onversion.ars/3 Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 11, 2009 Share Posted January 11, 2009 and some info here... http://www.atarimagazines.com/compute/issu...or_Apple_II.php Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 11, 2009 Share Posted January 11, 2009 http://z80.i-demo.pl/music.html Quote Link to comment Share on other sites More sharing options...
atariksi Posted January 13, 2009 Share Posted January 13, 2009 no! pokey/sid/ay have volume levels and you can play samples eg. 15,14,15,14... you got somting 14.5... but gtia have 1bit so: 1,0,1,0 - 0,5 ? heh no... on powerfull cpu with 1-bit you can generate multichannels with any wave: But accuracy decreases with more bit depth and higher frequency of samples to playback. I remember PC DAC simulator could only do about 64 levels at around 11Khz sampling rate and the levels dropped as the sampling rate increased. Quote Link to comment Share on other sites More sharing options...
+JAC! Posted January 13, 2009 Share Posted January 13, 2009 Hi XXL, This is cool stuff and the Tim Follin tracks sound really great. And full respect for the stuff of Mister Beep. What I'm wondering is, if there really is a big difference between using POKEY AUDCx direct volume control (as 1 bit) or GITA CONSOL as 1 bit. From the schematics I don't see any circuitry that should change the attack/decay in a different way (there is only one more op-amp in between). But a don't have a scope to check and my XL is 105 miles away until the weekend. Regards, Peter/JAC! Quote Link to comment Share on other sites More sharing options...
xxl Posted January 13, 2009 Author Share Posted January 13, 2009 > if there really is a big difference between using POKEY AUDCx direct volume control (as 1 bit) or GITA CONSOL as 1 bit. try this: http://atari.fandal.cz/detail.php?files_id=5909 - you can choice output POKEY/GTIA btw. today i rewrite Zilog's 4-channel player (with patterns - tracker player?). mp3 soon. Quote Link to comment Share on other sites More sharing options...
xxl Posted January 14, 2009 Author Share Posted January 14, 2009 (edited) Zilog's cover, 4-channels player (GTIA) http://atari.pl/jsw_beep.mp3 Edited January 14, 2009 by xxl Quote Link to comment Share on other sites More sharing options...
xxl Posted January 18, 2009 Author Share Posted January 18, 2009 http://atari.pl/bombo.mp3 - Miker (RMT conversion) - 4 channels http://atari.pl/vectron.mp3 - Tim Follin - 3 channels, volume control (different player than last follins one) Quote Link to comment Share on other sites More sharing options...
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