CD-ROM Digital out to TOS-link out Conversion
CD-ROM Digital out to TOS-link out Conversion
Shawn Lin ([email protected])
If you want to record from CD to MD digitally, but don't want to buy a
new CD player, I have a cheap solution that requires stuff you probably
already have - computer and CD-ROM drive. This may require a little bit
of skill with electronics, but not much. Read on if you're curious.
Most 2x or better CD-ROM drives have a 2-pin "DIGITAL AUDIO OUTPUT"
which is actually SPDIF. To convert this to TOSLINK optical signals,
you will need to purchase a TOSLINK transmitter module. This module has
three pins: GND, VCC, and INPUT.
- Hook up power to the module: Grab any available power connector
inside the computer. Connect one BLACK wire to the module's GND pin and
the RED wire to the module's VCC pin.
PINOUTS for TOSLINK module (viewed from the end cable plugs into, with
pins pointing down): INPUT VCC GND
- Now hook up CD-ROM drive's digital audio to the module: Connect the
GND from CD-ROM's Digital output to GND on the module. Connect the
DIGITAL OUTPUT pin (or whatever it may be called) from the CD-ROM to the
INPUT pin on the module.
- That's it! The module can be mounted wherever it is convenient. It
has a screw-hole on it, so it will probably look okay mounted in a spare
DB-9 hole in your case. Last thing to do is connect a TOSLINK cable
from the module to the MD recorder. Flip the recorder over to digital
input and hit RECORD. The MD recorder should put "Din Unlock" on the
display. Start playing the CD on the CD-ROM drive. If all went well,
you should now hear the CD playing through the MD recorder.
Connections are not critical. I temporarily used small aligator clips!
You can solder everything directly, or use connectors. The module is
also PC board mountable.
Every time the track changes on the CD, it does on the MD recorder too.
When CD stops, recording stops (goes back to Din Unlock).
Benefits: CD-ROM drive's digital-end is probably better than many
home-audio players because the CD-ROM drive is probably built to tighter
tolerances; it must be able to read data off of CD's many times faster
than normal (2x, 4x, 6x, 8x, 12x whatever) with minimal errors. I may
be wrong, but I also think CD-ROM drives have cheap DAC's. Audio CD's
played on the CD-ROM drive seem to sound better when played thru my
MDS-JE500's DAC, though it could just be all in my head.
Parts Sources
- TOSLINK cable $10 each at Core Sound http://www.panix.com/~moskowit
- TOSLINK transmitter module, SHARP GP1F32T, direct from SONY part
#8-749-921-12 $20 each... OR SHARP GP1F38T, SONY part #8-749-012-69
(don't know price, but GP1F38T is newer for what it's worth).
- Digikey, http://www.digikey.com
carries 2 and 3-pin connectors to plug into the CD-ROM and transmitter
module.
- Radio Shack sells 4-pin MOLEX connectors that you can modify
to make it plug into a power connector (can't find the actual
connectors).
- I'm not sure where to find small gauge shielded wire in
small quantities, but Radio Shack may carry some.
- If you don't have a
CD-ROM drive, typically they cost $10 per 'x' (i.e. $20 for a 2x, $40
for a 4x, etc.) Panasonic CD-ROM drives almost always have the
digital output as does AZTEC.