December 03, 2021, 04:47:05 AM

LaserActive YM2612 Sound

Started by blackevilweredragon, June 19, 2007, 08:02:41 PM

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blackevilweredragon

I don't have a laser active, but for it's optical out, this is what I'm wondering about.


The YM2612 has an internal FM DAC (to produce it's FM sounds on speakers), where, say, on an Adlib card, the YM3812 needs an external DAC.

Perhaps the YM2612 on the 315 chip has direct access to the pre-DAC digital audio, and those Pioneer chips re-sample/encode it into something optical audio can use?

I wish we had schematics to the laser actives 315 chip, i'd like to see if the audio does come out with the 2612's pre-dac data.  That could mean an even better mod for the Genesis 2 sound..

RobIvy64

Heh, no point in discussing it really.

SSF will disagree with me and the thread will get locked.
"Console Mods" lurker

blackevilweredragon

nah, we should be able to discuss it without getting the thread locked, as long as it stays on the debate of the 2612...

timofonic

Sorry for bumping another old post. What about this? I did read LaserActive converts from analog audio to digital.

Leynos

Hi timofonic,

You are correct.  There was some uncertainty some time ago as to whether or not this is the case, but I think it has long since been resolved.

My Laseractive seems to have a broken ADC, so whilst I get digital output from the redbook audio in CD games, none of the chip sounds are output.

Regards,

Leynos

Shou

Has it been confirmed that LA games, MD and PCE games running on the Packs actually output optical audio? I only have tested the NEC unit but I get no sound on Vajra, nothing from HUcard titles and only redbook from CD games which makes sense.
become history

l_oliveira

Two names for the same thing:

SPDIF:  Electrical specifications and encapsulation protocol for audio transfers on home theater setups. Uses an serial electric line. Usual setup is either non buffered 5v/3v level TTL signals or high power for transfer between units (orange coax cable)

TOSLINK:  Optical interface which uses an optical fiber cable to transfer the data. Electrical isolation is achieved with this method. Uses the same encapsulation protocol as SPDIF.


The Laser Active probably uses TTL level SPDIF signal for the chips audio. There's an high pin count Pioneer LSI in each pack module. It's possible that the said LSI has the ADC internally. Once the SPDIF signal is encoded, if the single wire communication line is interrupted, no sound will be heard regardless how many analog outputs are multiplexed in it.

NFG

I think you misunderstand the question, l_oliveira.  Either that or I misunderstood your answer.  ;)

He's asking if game sounds are heard on the optical output, or just CD digital audio.

l_oliveira

Quote from: Lawrence on April 17, 2010, 05:54:08 PM
I think you misunderstand the question, l_oliveira. 

I suppose that's the case ... lol
Anyway I'd love to have the chance to lay my grubby fingers on a LaserActive unit... Yes, Yes ... Hahaha :)

NFG

I should really drag mine out of the box it's in.  ^_^

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