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Offline amiadudeorwat

Re: Prisma?
« on: November 15, 2016, 02:51:06 AM »
What he could do is connect the CD Audio header to the A4000 motherboard header, since the Paula Audio connects to the Prisma header anyway.
 

Offline amiadudeorwat

Re: Prisma?
« Reply #1 on: November 18, 2016, 02:42:35 AM »
Quote from: danwood;816451
True, but the A4000's motherboard header has a weird, non-standard pin layout.  I did make up a special cable to fit it a few years ago, but it was very unbalanced, CD audio was very quiet and Paula output really loud.  Will be much nicer when the Prisma does it, I imagine.

Yes that is true the A4000 CD audio volume on the header is known to be low, some speculate it was so CD Music wouldn't be too loud over SFX in games.  There are however two easy fixes.

https://groups.google.com/forum/#!topic/z-netz.rechner.amiga.hardware/f3Lh-RwYJbU

Replace resistors or AsimCDFS lets you play the CDDA without the audio header at all, but I'm not sure if that just renders it via Paula.
 

Offline amiadudeorwat

Re: Prisma?
« Reply #2 on: November 19, 2016, 12:59:32 AM »
The playing audio without the cable with AsimCDFS I'm quite sure just  renders it down to Paula audio so it probably sounds bad compared to CD  quality.  This has been a feature on Wintel machines for a long time (and apparently some Amiga CD player programs) it just sends the CDDA over the IDE or SCSI bus, but since it's digital it has to go through Paula to make it out to the speakers.

The resistor method is kind of a pain, as the second  resistor is on the bottom of the motherboard so it means complete  disassembly, but if that's not a big deal then it's simple enough to  do.  

All that being said the Prisma should support this  feature.  It is to me a minor scandal that such a simple feature doesn't  work out of the box.  Maybe the wiki should be updated under the -CDDA  header (Yes it's there, it doesn't do anything currently).  

With the four connectors on the breakout, maybe one of them is a secondary input and the CDDA could be connected that way?

Back  to the years old discussion on this, I understand *It's not a sound  card, just a multiformat decoder* since WAV is one of the formats it  supports, why couldn't AHI be adapted to send WAV encoded audio to it?
 

Offline amiadudeorwat

Re: Prisma?
« Reply #3 on: November 22, 2016, 11:56:19 PM »
Quote from: QuikSanz;816745
Agree! If I can't hook it thru my sound card it's no use.

If you have a sound card like an SB128 or an FM801 you probably already have Paula connecting into the line-in of this card.  You could route the speaker out from the sound card to the line in of the Prisma.  Or connect the speaker-out from Prisma to the line in of the sound card.

The issue Dan was having of only one channel working is probably just a bad solder joint or a dodgy connector somewhere, bad luck that it went to someone that would post a review.

Some documentation of those extra two connectors would be nice.  Maybe they do nothing and are for future expansion.
« Last Edit: November 22, 2016, 11:57:54 PM by amiadudeorwat »