CDROM Audio Connectors
The CD plays music via it's audio connector cable. It is does not pass though the CD controller ribbon.
Years ago, every CDROM manufacturer and sound card company used their own connectors. Since you had three major sound card interfaces, Creative Labs, and two from Media Vision, and almost 10 different CDROM sound port connectors, you can see the number of interface cables was huge. I have a rather large box of Creative labs to Plextor, to NEC, to Sony etc. They are all $10 each or so each. Unfortunately for me, the new, IDE CDROMs usually come with free audio, MPC-2 cable.
Then Media Vision died and the CDROM manufacturers decided to standardize on common connector. This is the MPC-2 connector. It is big, usually black, and has a squeeze locking key. It hangs out of the card or CDROM enough to hold the plug and push the release tab at the same time. The MPC-2 is the connector found on 99% of all CDROMs these days. It was a major improvement. All other connectors rely on friction to secure the connector. Most of the old connectors didn't have any place to get your fingers on, so people ended up pulling on the wires in desperation. The result was a lot of broken sound card wires. You would think that with the MPC-2 CDROM connector and only one sound card interface, life would be good. Not so fast, buddy.
Creative Labs still had a ton of their connectors on the shelf. It is a little, white, square block with a keyed top and four pins. They had 3 wires -- red for right, white for left, and a black for ground. The socket side of this connector is almost free, and the plug is also cheap. So for a while most of the cards still being sold had the Creative Labs connector.
When I bought CDROMs they came with sound cables with the Creative connector on one end and the MPC-2 for the CD on the other. Later Creative labs changed the connectors so that the sound card used the MPC-2 connector.
But even these Creative Labs sound cards were not the same. For some odd reason most of the SB16 and SB32 family used one pinout and the SB64AWE used another. Why? Someone probably messed up a circuit card layout and didn't correct it.
The above figure shows the two pinouts of the sound blaster connectors. The view is from the wire side. O is for open, L for left, G for ground, and R for right. Not all of the SB64 family uses the same pinout either, so you need to do check on your card to see which pinout you have. The only difference is connection for the left channel. If your sound card is working perfectly and the CD only plays one channel in audio mode, you might have the wrong cable between the CDROM and the sound card. As an interesting side note, the MPC-2 connector uses the same wiring pattern of R-O-G-L. The view is from the wire side. The table below might help.
|Sound Card||Creative Number||Pinout|
|SB32AWE, IDE||CT3670||Standard Creative|
|SB64AWE Value||CT4500||Standard MPC-2|
|SB64AWE||CT4520||Alternate Creative on AUX. port
Standard MPC-2 on CDROM
|SB Vibra 16XV||CT4170||Standard MPC-2|
|SB16, AT||CT2230||Standard Creative|
|SB Vibra 16C||CT4180||Standard Creative J2 or MPC-2 on J3*
AUX. Connector J1 uses Alternate pattern
|SB16 w/IDE||CT2940||Standard Creative, and MPC-2|
* The CT4180, Vibra 16C, had a couple of different models. The silk screen and board allow for a Standard Creative CDROM connector for the CDROM as J2 and an MPC-2 socket as J3. J2 , however, blocks the pins of J3. So the sound card might have the MPC-2 connector or the Creative connector, J2, but not both. The AUX1 connector, which sits right next to J2, is a Creative Labs connector. However, it uses the alternate wire pattern of the SB64AWE. So you have a sound card that might bite you if you are not careful and watch what connector you pick. J1 and J2 are mechanically identical. They look the same, but they aren't.
Now most new sound cards and CDROMs use the same MPC-2 plug on both ends with the same pinout. Gee. What a concept. It only took five years.
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