How does G4 audio work?

Hi, G4-533 -

Welcome to Apple's Discussions.

Also, can I pull the Zip drive and replace it with a second hard drive?

Folk have done that, but it is not easy - the bay used by the Zip drive is too small for a normal-size hard drive. To get one to fit you'd need to do a bit of surgery on the internal frame of the G4; due care is necessary to avoid getting bits of metal in the logic board or other places where they can do harm.

Another way would be to get a pocket-size drive, like one used in a pocket-size firewire drive.

However, given the design flow of the cooling air inside the case, heat from a hard drive in that location can be of concern.

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The real solution is to just add a second drive on top of the first one in the main bay - G4s come pre-equipped for that, typically with a two-drive sled that allows stacking the drives in the rear position, and with a spare power connector adjacent to that spot as well as a spare connector on the IDE cable.

G4 (DA) models such as yours should use the Master and Slave jumper settings when you have two drives on the built-in bus.

You can view/download a how-to PDF and/or movieclip from this page -
http://docs.info.apple.com/article.html?artnum=75313

If you are missing the two-drive sled (bracket), you can get one from sites like this one -
http://www.welovemacs.com/8052322a.html

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With the addition of a PCI ATA controller card, you can have up to four drives in normal positions in the main drive bay - two in the rear on the two-drive sled, plus one in the middle and one in the front positions.

Some while back one regular posted that he'd managed to get seven hard drives into a G4 (DA) case - he also modified the cooling system to accommodate the increased heat load.

I was given a MAC G4 digital audio with missing
memory and hard-drive. I installed a gig of PC133
memory and a WD 20 gig hard drive. I replaced the CD
writer with a DVD combo drive. To my surprise there
were no audio connections on the drive. The audio
quality is great but how the heck does it get from
the drive to the main logic board?

That's why it's called the Digital Audio Mac. It doesn't use the analog audio output from the optical drive, but reads the digital audio from the disk. Software does any necessary audio processing and sends the output to digital to analog converters on the main logic board.

The computer reads the digital audio data just the way it would read any digital data from a disk. Some early CD-ROM drives would only let the computer read data CDs, not read the digital data from audio CDs. The computer could control the audio CD to select tracks, etc., but the audio had to come from the analog connector on the drive. With the digital audio, the data can be stored in a disk file for use by iTunes.