topgun@chaos.cs.brandeis.edu (Chandra Bajpai) (03/01/90)
What type of sound chip does the STE use? Is it different from the ST? Does the quality of the sound chip rival that of the Mac II/NeXT/Amiga? Can some one list the specs of the STE? -topgun@brandeis.cs.edu
apratt@atari.UUCP (Allan Pratt) (03/02/90)
topgun@chaos.cs.brandeis.edu (Chandra Bajpai) writes: >What type of sound chip does the STE use? Is it different from the ST? >Does the quality of the sound chip rival that of the Mac II/NeXT/Amiga? The STe has two sound subsystems. One is like the ST's: it's a Yamaha PSG (Programmable Sound Generator), also available from General Instruments (I think), which is why you see it referred to as "The PSG" and "The GI Sound Chip." The other sound subsystem in the STe is our own creation: it's a two-channel 8-bit digital-to-analog converter which is fed by DMA (direct memory access), which means the processor can set it up and then go do something else while it's playing. You will hear that referred to as "digital sound" or "DMA sound." Data goes to the DAC at 50KHz, 25KHz, 12.5KHz, or 6.25KHz, selected in software. There are two channels, one left and one right. You can play monaural sound out BOTH speakers and use only half the data. The quality is very good. I don't know how to quantify that. Remember that digital sound is only as good as your sampler plus your playback (including amp and speakers), and the STe serves as part of the playback system: you provide the amp and speakers. The sound will come out the monitor's speaker, but that's not stereo and it's just not up to the task. The NeXT box has a DSP (digital signal processor), which doesn't just play back sound, it GENERATES it from formulas or other data. That's a different beast altogether. Amiga's the same way. I guess those chips can simply play a sampled sound, and I don't know how to compare them against the STe's sound capability. The STe is certainly better than the Mac's digital-sound-output mode: the (highest) sampling rate is higher and we use better filters to smooth out the "jaggies." For more technical specs you'll have to write to Atari; I don't know anything about audio electronics. ============================================ Opinions expressed above do not necessarily -- Allan Pratt, Atari Corp. reflect those of Atari Corp. or anyone else. ...ames!atari!apratt
hyc@math.lsa.umich.edu (Howard Chu) (03/03/90)
In article <2062@atari.UUCP> apratt@atari.UUCP (Allan Pratt) writes: >The NeXT box has a DSP (digital signal processor), which doesn't just >play back sound, it GENERATES it from formulas or other data. That's a >different beast altogether. Amiga's the same way. I guess those chips >can simply play a sampled sound, and I don't know how to compare them >against the STe's sound capability. The STe is certainly better than >the Mac's digital-sound-output mode: the (highest) sampling rate is >higher and we use better filters to smooth out the "jaggies." Well, the DSP in a NeXT can do some pretty amazing things, but it's a silly use for that hardware. I like setting up sound routines in the background and then going my merry way hacking/etc. on the ST. On the NeXT, you don't get any sound of any kind when the DSP is used for any computational purposes. That is, unlike a disk drive, there's no way to share access to the DSP between multiple tasks. Also, for most of the stuff I've played with, the sound is cut-off whenever other tasks are driving up CPU and disk use. This makes no sense to me, since the DSP should be executing its program independently of the 68030. But the end result is that sound on the NeXT gets chopped up horribly if you try to do anything else along with it. (Like open a new window.) Cute, isn't it? Steve Jobs turned a wonderful processor (68000) into a toaster (Thin Mac). Now he's turned Unix on a 68030 into a single-user single-tasking non-operating system. Will wonders never cease. I wish they would... -- -- Howard Chu @ University of Michigan
blee@plains.UUCP (Blaine Lee SEE ADVTISMENT ) (03/03/90)
In article <11231@stag.math.lsa.umich.edu> hyc@math.lsa.umich.edu (Howard Chu) writes: >In article <2062@atari.UUCP> apratt@atari.UUCP (Allan Pratt) writes: >>The NeXT box has a DSP (digital signal processor), which doesn't just >>play back sound, it GENERATES it from formulas or other data. That's a > >share access to the DSP between multiple tasks. Also, for most of the >stuff I've played with, the sound is cut-off whenever other tasks are >driving up CPU and disk use. This makes no sense to me, since the DSP >should be executing its program independently of the 68030. But the >end result is that sound on the NeXT gets chopped up horribly if you >try to do anything else along with it. (Like open a new window.) > >Cute, isn't it? Steve Jobs turned a wonderful processor (68000) into a >toaster (Thin Mac). Now he's turned Unix on a 68030 into a single-user >single-tasking non-operating system. Will wonders never cease. I wish >they would... >-- > -- Howard Chu @ University of Michigan Not that I can claim that I know what I am talking about...but... From a early article in Byte on the NeXT I seem to remeber the memory that the DSP has is quite limited. I would guess that the 68030 has to swap in new data all the time. Isn't the *only* reason it was installed was for 'CD' quality sound... wasn't the 030 supposed to handle the tasks? Working on release 0.9, I am amazed every time I log onto it... just wait until it gets to 1.4...(isn't that the magic number??) Another thought: How many songs do you want to hear concurently? PS: see you on comp.sys.next Since I don't think Mr Jobs will be able to reply I felt someone should offer a little reality. Blaine Lee blee @ plains.nodak.edu