MC wrote:nelson_a wrote:Unless you're using an active converter, such as the following:
https://www.pacrad.com/henry-engineerin … h-2x6.html
...I think you're going to encounter quite a bit of signal degradation / loss (when it comes to passively converting SPDIF to AES).
There is no 'signal degradation / loss'. If the sender has a problematic output stage all that could happen is that there will be no Sync, but unstable Sync/Lock/No Lock state with clicks and pops. The ADI-2 Pro clearly shows that. In nearly all cases such a connection will just work, which is why this cable adapter is mentioned in all our manuals.
Please explain why there could be 'quite a bit of signal degradation / loss', which reads to me like 'change in sound'.
Hello MC,
There are a few big differences between SPDIF and AES:
1. SPDIF is unbalanced, whereas AES is balanced.
2. SPDIF utilizes 75 Ohms of impedance, whereas AES utilizes 110 Ohms of impedance.
3. SPDIF output level is 0.5 volts, whereas AES is 2 - 7 volts.
4. SPDIF max current is 8 milli-amps, whereas AES is 64 milli-amps.
...there are also some subtle differences
1. SPDIF and AES utilize different sub-code formats, so a passive converter would not be able to properly convert SPDIF to AES (or vice-versa).
2. Going from AES to SPDIF is not the same both ways. In other words, going from SPDIF to AES is easier than going from AES to SPDIF.
The big issue with passive conversion is that, though impedance is easily taken care of with a passive converter, the level and drive differences between AES and SPDIF are not.
Note: You can read more about the technical differences between AES and SPDIF here: http://www.rane.com/note149.html
Lastly, I've heard it said many times that AES tends to sound cleaner than SPDIF (which makes sense given that AES is balanced whereas SPDIF is not). I'd imagine this phenomena grows the greater the length of the cables being used as well as the greater the amount of signal interference.
So, a cleaner sound (compared to a not so clean sound), will color things differently, and hence sound different.
Now all of that being said, the OP may not care about those minor differences. But to say there are no differences and that everything will sound exactly the same, is simply not true.
Nelson
