Slow Prelude 1200

CU_AMiGA · 05 April 2006, 16:32

Hey Yo!

Recently purchased a Prelude 1200. Got Prelude 1200 hardware installed, plus the software installed (Prelude CD and AHI off websites). Thing is, mp3 playback is really slow (and the whole system slows down) when using mp3 players. Apart from using SongPlayer, but even that slows down a bit. Anyway ideas?

Regards,

keropi · 05 April 2006, 19:54

what cpu u got? AFAIK prelude does not decode in its own hardware mp3's...

DoctorQ · 05 April 2006, 20:09

As Keropi mentions, the Prelude hasn't gotten any hardware decoding for MP3s. You will need the MPEGit expansion, but it only works with the Zorro version of the Prelude.

Only other solution is a MAS Player, or a PPC CPU, to lower the CPU usage when playing MP3s.

Flashlab · 05 April 2006, 20:11

AFAIK your card doesn't have a DSP that can decode MP3's. So your CPU does the hard work; hence the slowdown. There are a few cards that do decode MP3 in hardware. One card is the Delfina.

ant512 · 05 April 2006, 22:28

Watch out for compatibility problems with the Delfina, though, and also note that the card's drivers are really shoddy (to the extent that Michael Henke, an end-user, had to write his own patch to make them even remotely useful).

For MP3 playback on the Prelude, I found that MPEGA gave the best quality/performance ratio. Choose the executable for your CPU (don't bother with the FPU versions - they're slower and don't noticably improve the sound quality) and drop the quality ("divider", or something like that) down to 1/2. That should give you acceptible playback.

Of course, this all depends on the speed of your CPU. An 030 can play 128Kbps MP3s if you drop the frequency to 22KHz and the quality to 1/4. An 060 can play full-quality 128Kbps, or 192Kbps with the quality at 1/2, and still have enough CPU time left over to run a few simple applications.

You'll find that playback through Paula leaves your system more responsive than playback through the Prelude - this is because Paula only outputs in 8-bit, so the 16-bit Prelude has a lot more work to do.

keropi · 06 April 2006, 07:32

unless you have a ppc then don't bother with mp3 playback...

CU_AMiGA · 06 April 2006, 15:27

Hey Yo!

Many thanks for the reply. Just for the record i have a 060@50mhz plus 64meg RAM. I personally thought that the slowdown would be either because of clockport timings, or because of slower CPU (what has been mentioned here). DAMN! I thought that this soundcard would make mp3 playback more faster, judging from this misleading review of the Prelude 1200:

http://www.infinitefrontiers.0catch.com/Prelude1200.htm

Anyway, i messed around with some drivers of the Prelude and AHI, and have got the playback a little faster under SongPlayer and AmigaAMP. I get full 44.1 16-but playback as long as i don't do anything else - even move the mouse!!! What version Delfina is the best then?

ant512 · 06 April 2006, 15:38

In my experience, the Delfina is a waste of time. It does not work in either of my Blizzard 1260-accelerated Amigas. It works in the Blizzard 1230-IV machine, but as that doesn't have the memory or the CPU power run the software I bought the Delfina for, there's no point in installing it in that computer.

There are three versions of the Delfina board. There's the Zorro version for bigbox Amigas and towered 1200s with a Zorro busboard; there's the original Petsoft clockport version, and the Individual Computers clockport version. The Flipper interface, which supposedly connected a clockport Delfina to a Zorro card, was vapourware.

As the Delfina doesn't work in my 060 machines I haven't really used it much, but I do know the following:

- The standard MP3 libraries are crap, and you need to use Michael Henke's patched version if you want to play MP3s;
- Michael Henke's patched libraries are old versions, and might have compatibility problems with the Individual Computer Delfina boards;
- The DSP on the card, that handles MP3 decoding, is unstable (either bad drivers or buggy hardware) and keeps crashing, requiring a power cycle of the entire computer before it starts working again.

In conclusion - don't bother with a Delfina. The Prelude1200 is a perfectly servicable card (though it seems to have problems with OctaMED Sound Studio). If you need to listen to MP3s, save some money and buy a cheap flash memory-based USB player, or treat yourself to an iPod if money is no object.

As for the review you linked to, it was clearly written by a crazed Amiga apologist. He doesn't understand how MP3 playback works (the effort is in decompressing the data, not mixing it), and anyone who would give the Prelude1200 97% when it is little more than a bog-standard Crystal soundchip on a custom PCB has no grasp of reality. This is precisely the sort of rabid, factless propaganda that makes me stay away from the Amiga One.

Doc Mindie · 07 April 2006, 13:57

ant.... feel free to stuff your delfina card my way :look

CU_AMiGA · 07 April 2006, 14:21

Hey Yo!

I take it that the statment saying that "Quake runs 50% faster on 040" is BS as well then? Ant, are you sure that problem isn't because you may have an early rev of the board you're using?

Regards,

ant512 · 09 April 2006, 01:38

Quote:

Originally Posted by CU_AMiGA

I take it that the statment saying that "Quake runs 50% faster on 040" is BS as well then? Ant, are you sure that problem isn't because you may have an early rev of the board you're using?

50% faster!? Heh, funny. Playing back sound through the Prelude will actually slow Quake down, because AHI will have more work to do. Whichever way you look at it, shoving 16-bit data around in memory takes twice the work that shoving 8-bit data around does, as there are twice as many bits flying around. Mixing and processing 16-bit data is more CPU intensive than 8-bit data*.

The only gain you'd possibly get from having a sound card is that the CPU doesn't have to worry about playing back the sound - that can be handled by the sound card. As audio playback on the Amiga is handled by Paula anyway, the benefit is negated.

Anyway, you can switch the audio off in Quake completely, and it really doesn't affect the speed of the game. Quake runs slowly because the m68K series of processors simply aren't fast enough to handle the complex mathematics behind the 3D engine, not because the samples are being played back in 8-bit quality. I repeat - the guy who wrote this review is deluded.

Oh, and this is completely false:

Quote:

These two formats were made popular on the PC and allow multiple 16-bit channels for music, with many modules playing in 8, 10, 12, 16, or even more channels. Normally, for Amiga module players to handle these, they mix the samples real time and play them back through the Amiga's internal sound chip and tend to suffer in terms of quality. Unless you have a reasonably nippy processor, they don't play back too well. However, when using Prelude, each channel can be allocated separately, plays back in full 16-bit and they sound pretty amazing (as long as the original module is any good!).

Most cheap PC soundcards of the Prelude's vintage have just two sound channels - one left, one right. The Prelude is no exception. Multichannel PC modules are mixed down in realtime to the two channels. You don't noticably lose any quality because the card remixes in 16-bit; mixing in 8-bits does create an audible loss of quality. Modern PC soundcards have more channels; this is simply because most modern cards support surround-sound. Samples are still mixed down for each speaker.

Pretty sure the Delfina I've got dates from at least a couple of years after Individual's release of the board; in theory, the bugs should have been ironed out by Petsoft before Individual got anywhere near it. I had a brief email exchange with Jens Schoenfeld when I first got the card - he confirmed that there is a compability problem with 040/060 cards, but he stopped communicating once we'd established that the card worked OK with an 030 accelerator.

---

*Might be worth checking this out - since the m68K CPU can process 16-bit words, I'm not entirely sure that manipulating 16-bit data will be slower. However, I'm pretty sure that, from a memory point of view, reading and writing 16-bit data is slower. I'm reading the m68K handbook at the moment, exciting as it is, so hopefully I should know the answer soon...

CU_AMiGA · 10 April 2006, 15:20

Hey Yo!

Yeah should be interesting to find out. I have got SongPlayer now running 128/192kbps MP3 with no quality loss or speed reductions. The Prelude 1200 is a good card, but i feel that the Zorro Prelude with the MPEGiT add-on is the ulitmate!

Cheers

Mad-Matt · 10 April 2006, 20:33

The Melody A1200 is more like the ultimate for a clock port expantion with its hardware dsp to take the load off mp3 processing.

Im using a soundblaster128 though a mediator at the moment and unfortunatly due to the rarther slow zorroII of the A1200, is shit ass slow to use. So even though I have access to 16bit modes, the ahi 14bit paula mixer is far faster, and the end result isnt much different from the sb128. Even with ppc, the mediator bottleneck makes it impossable to do much else with my machine while its playing back high quality mp3 through the sb128. Also the 14bit Deliplayer plugin in ahi 16bit mode is usless on sb128, just not enough cpu power from my poor 040 to even add effects to 4 track protracker modules. The plugin is far superior through good ole paula

.

keropi · 11 April 2006, 07:46

really? I have no prob whatsoever to play 192kbps/44khz/16bit mp3's on the background on my g-rex->ess solo1 using the ppc, the 060 is free for os3.9 and there is only a very very minimal delay...

CU_AMiGA · 25 April 2006, 17:02

Quote:

Originally Posted by Mad-Matt

The Melody A1200 is more like the ultimate for a clock port expantion with its hardware dsp to take the load off mp3 processing.

Im using a soundblaster128 though a mediator at the moment and unfortunatly due to the rarther slow zorroII of the A1200, is shit ass slow to use. So even though I have access to 16bit modes, the ahi 14bit paula mixer is far faster, and the end result isnt much different from the sb128. Even with ppc, the mediator bottleneck makes it impossable to do much else with my machine while its playing back high quality mp3 through the sb128. Also the 14bit Deliplayer plugin in ahi 16bit mode is usless on sb128, just not enough cpu power from my poor 040 to even add effects to 4 track protracker modules. The plugin is far superior through good ole paula

.

Hey Yo!

Yeah but is the DSP on the Melody 1200 used for MP3's? I thought the DSP on that was for MPEG 2.5 layer I (mp1) and II (mp2). Anyway, i have got Prelude 1200 running pretty well. I think i'll keep it, unless someone has a Catweisel MKIII A1200 they're willing to part exchange!

Best Regards,

05 April 2006, 16:32	#1
CU_AMiGA Banned Join Date: Dec 2003 Location: Exeter Age: 38 Posts: 970	Slow Prelude 1200 Hey Yo! Recently purchased a Prelude 1200. Got Prelude 1200 hardware installed, plus the software installed (Prelude CD and AHI off websites). Thing is, mp3 playback is really slow (and the whole system slows down) when using mp3 players. Apart from using SongPlayer, but even that slows down a bit. Anyway ideas? Regards,

06 April 2006, 15:38	#8
ant512 Registered User Join Date: Dec 2002 Location: California Posts: 965	In my experience, the Delfina is a waste of time. It does not work in either of my Blizzard 1260-accelerated Amigas. It works in the Blizzard 1230-IV machine, but as that doesn't have the memory or the CPU power run the software I bought the Delfina for, there's no point in installing it in that computer. There are three versions of the Delfina board. There's the Zorro version for bigbox Amigas and towered 1200s with a Zorro busboard; there's the original Petsoft clockport version, and the Individual Computers clockport version. The Flipper interface, which supposedly connected a clockport Delfina to a Zorro card, was vapourware. As the Delfina doesn't work in my 060 machines I haven't really used it much, but I do know the following: - The standard MP3 libraries are crap, and you need to use Michael Henke's patched version if you want to play MP3s; - Michael Henke's patched libraries are old versions, and might have compatibility problems with the Individual Computer Delfina boards; - The DSP on the card, that handles MP3 decoding, is unstable (either bad drivers or buggy hardware) and keeps crashing, requiring a power cycle of the entire computer before it starts working again. In conclusion - don't bother with a Delfina. The Prelude1200 is a perfectly servicable card (though it seems to have problems with OctaMED Sound Studio). If you need to listen to MP3s, save some money and buy a cheap flash memory-based USB player, or treat yourself to an iPod if money is no object. As for the review you linked to, it was clearly written by a crazed Amiga apologist. He doesn't understand how MP3 playback works (the effort is in decompressing the data, not mixing it), and anyone who would give the Prelude1200 97% when it is little more than a bog-standard Crystal soundchip on a custom PCB has no grasp of reality. This is precisely the sort of rabid, factless propaganda that makes me stay away from the Amiga One. Last edited by ant512; 06 April 2006 at 15:45.

07 April 2006, 14:21	#10
CU_AMiGA Banned Join Date: Dec 2003 Location: Exeter Age: 38 Posts: 970	Hey Yo! I take it that the statment saying that "Quake runs 50% faster on 040" is BS as well then? Ant, are you sure that problem isn't because you may have an early rev of the board you're using? Regards, Last edited by CU_AMiGA; 07 April 2006 at 14:26.

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05 April 2006, 19:54	#2
keropi . Join Date: Oct 2004 Location: Ioannina/Greece Posts: 5,040	what cpu u got? AFAIK prelude does not decode in its own hardware mp3's...

05 April 2006, 20:09	#3
DoctorQ What?? Who?? DoctorQ!! Join Date: Jun 2005 Location: Rødding/Denmark Age: 43 Posts: 314	As Keropi mentions, the Prelude hasn't gotten any hardware decoding for MP3s. You will need the MPEGit expansion, but it only works with the Zorro version of the Prelude. Only other solution is a MAS Player, or a PPC CPU, to lower the CPU usage when playing MP3s.

05 April 2006, 20:11	#4
Flashlab Registered User Join Date: Sep 2005 Location: Netherlands Posts: 158	AFAIK your card doesn't have a DSP that can decode MP3's. So your CPU does the hard work; hence the slowdown. There are a few cards that do decode MP3 in hardware. One card is the Delfina.

05 April 2006, 22:28	#5
ant512 Registered User Join Date: Dec 2002 Location: California Posts: 965	Watch out for compatibility problems with the Delfina, though, and also note that the card's drivers are really shoddy (to the extent that Michael Henke, an end-user, had to write his own patch to make them even remotely useful). For MP3 playback on the Prelude, I found that MPEGA gave the best quality/performance ratio. Choose the executable for your CPU (don't bother with the FPU versions - they're slower and don't noticably improve the sound quality) and drop the quality ("divider", or something like that) down to 1/2. That should give you acceptible playback. Of course, this all depends on the speed of your CPU. An 030 can play 128Kbps MP3s if you drop the frequency to 22KHz and the quality to 1/4. An 060 can play full-quality 128Kbps, or 192Kbps with the quality at 1/2, and still have enough CPU time left over to run a few simple applications. You'll find that playback through Paula leaves your system more responsive than playback through the Prelude - this is because Paula only outputs in 8-bit, so the 16-bit Prelude has a lot more work to do.

06 April 2006, 07:32	#6
keropi . Join Date: Oct 2004 Location: Ioannina/Greece Posts: 5,040	unless you have a ppc then don't bother with mp3 playback...

06 April 2006, 15:27	#7
CU_AMiGA Banned Join Date: Dec 2003 Location: Exeter Age: 38 Posts: 970	Hey Yo! Many thanks for the reply. Just for the record i have a 060@50mhz plus 64meg RAM. I personally thought that the slowdown would be either because of clockport timings, or because of slower CPU (what has been mentioned here). DAMN! I thought that this soundcard would make mp3 playback more faster, judging from this misleading review of the Prelude 1200: http://www.infinitefrontiers.0catch.com/Prelude1200.htm Anyway, i messed around with some drivers of the Prelude and AHI, and have got the playback a little faster under SongPlayer and AmigaAMP. I get full 44.1 16-but playback as long as i don't do anything else - even move the mouse!!! What version Delfina is the best then?

07 April 2006, 13:57	#9
Doc Mindie In deep Trouble Join Date: Sep 2004 Location: Manchester, Made in Norway Age: 51 Posts: 841	ant.... feel free to stuff your delfina card my way :look

10 April 2006, 15:20	#12
CU_AMiGA Banned Join Date: Dec 2003 Location: Exeter Age: 38 Posts: 970	Hey Yo! Yeah should be interesting to find out. I have got SongPlayer now running 128/192kbps MP3 with no quality loss or speed reductions. The Prelude 1200 is a good card, but i feel that the Zorro Prelude with the MPEGiT add-on is the ulitmate! Cheers

10 April 2006, 20:33	#13
Mad-Matt Longplayer Join Date: Jan 2005 Location: Lincoln / UK Age: 44 Posts: 1,848	The Melody A1200 is more like the ultimate for a clock port expantion with its hardware dsp to take the load off mp3 processing. Im using a soundblaster128 though a mediator at the moment and unfortunatly due to the rarther slow zorroII of the A1200, is shit ass slow to use. So even though I have access to 16bit modes, the ahi 14bit paula mixer is far faster, and the end result isnt much different from the sb128. Even with ppc, the mediator bottleneck makes it impossable to do much else with my machine while its playing back high quality mp3 through the sb128. Also the 14bit Deliplayer plugin in ahi 16bit mode is usless on sb128, just not enough cpu power from my poor 040 to even add effects to 4 track protracker modules. The plugin is far superior through good ole paula .

11 April 2006, 07:46	#14
keropi . Join Date: Oct 2004 Location: Ioannina/Greece Posts: 5,040	really? I have no prob whatsoever to play 192kbps/44khz/16bit mp3's on the background on my g-rex->ess solo1 using the ppc, the 060 is free for os3.9 and there is only a very very minimal delay...

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