I got an problem;
i hear an digital sound looks like static sound when connected the
digital output to an DAC i have convert the SPdif TTL to COAX
does anyone knows this problem
i hear an digital sound looks like static sound when connected the
digital output to an DAC i have convert the SPdif TTL to COAX
does anyone knows this problem
I was always under the impresion that SPDIF was a coaxial connection. Maybe you mean you converted a Toslink or other optical to coaxial.
Please forgive me if i am wrong.
Regards Ian
Please forgive me if i am wrong.
Regards Ian
I only hear this with using THE digital output
Of THE dvd rom to be sure i have converted THE ttl
To normal voltage use for coax
Of THE dvd rom to be sure i have converted THE ttl
To normal voltage use for coax
Spdif digital from CDROM = 5 v ttl
I have this with capacitor and two resistors
And THE DAC Locked good.
I have this with capacitor and two resistors
And THE DAC Locked good.
"Two resitors" - that's your problem.
The coax SPDIF is a 75 ohm input. In order to build a passive divider you need to end up with the same impedance at the source - so your divider should be 75 ohms to ground.
That would overload any CDROM digital output, since those are made to work with 1 kohm loads.
If you do a divider with unmatched impedance (1 kohm), you will have "reflections" of the signal on the connecting cable (especially if it is short) and you end up with noise.
The coax SPDIF is a 75 ohm input. In order to build a passive divider you need to end up with the same impedance at the source - so your divider should be 75 ohms to ground.
That would overload any CDROM digital output, since those are made to work with 1 kohm loads.
If you do a divider with unmatched impedance (1 kohm), you will have "reflections" of the signal on the connecting cable (especially if it is short) and you end up with noise.
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Do you have an schematic for so i can try
I have use also with 100 nF PE65612 paralel 75 ohm to ground same problem
Use several DAC and dvd-rom and CDROM players
I have use also with 100 nF PE65612 paralel 75 ohm to ground same problem
Use several DAC and dvd-rom and CDROM players
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You'll find most DAC inputs are 5v tolerant - you should be able to connect your TTL input directly to it.
SPDIF is a bitstream protocol, and can be passed over any medium. TTL is just 0-5v square wave. "Coaxial" is 75 ohm transformer coupled, 0.5v peak-peak. AES/EBU is a balanced 100 ohm signal. TOSLINK is an optical transmission system.
SPDIF is a bitstream protocol, and can be passed over any medium. TTL is just 0-5v square wave. "Coaxial" is 75 ohm transformer coupled, 0.5v peak-peak. AES/EBU is a balanced 100 ohm signal. TOSLINK is an optical transmission system.
Yes it woks also if i connect the digital output to the dac but the sound is totally better
when converting it but then i hear an static sound
I have now
---100 NF ---00000--|----------- digital
....................T1.... 75 ohm
-------------00000 --|----------- GND
when converting it but then i hear an static sound
I have now
---100 NF ---00000--|----------- digital
....................T1.... 75 ohm
-------------00000 --|----------- GND
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