Phono Box DS3 B output impedance

Thanks a lot for those explanations, guys.

I'm reaching my limits in terms of understanding resistance and electricity but I will slowly learn and then understand what you're talking about.

As far as the sound quality is concerned, it's fine the way I'm going now. But you know, it's always better to match what you hear with the good figures so you are sure that everything is fine. Want to be sure that I made nothing wrong that could have an undesirable effect later...

What I was concerned about mostly is: I wondered if there could be damages if input Z is too low and output Z too high. From what I read it seems that it's not the case, but better to be sure.

"How can you not know this and still spout all kinds of technical details here?" Because I only write what I think is correct.  However, I am not an engineer, not infallible, and I can make mistakes.  When I am in the wrong, I like to be corrected, because I will have learned something. Your point about cable impedance is making me think again about what I thought I knew.  I thought cable impedance enters into the calculation only at RF level frequencies. I thought that at audio frequencies, we need only worry about cable resistance, which in this case is only a few ohms, at most. Cable resistance (not impedance) can be ignored in this instance, or so I thought. If I was putting out incorrect information, I apologize to the OP, and thanks for correcting me. I'd like it if someone else can comment on this particular point.

@lewm, don't worry about that, I'm grateful for your help so nevermind if it happens to be not 100% exact. Thing is, I'm gathering some informations and will draw conclusions later.

I've read that XLR cables have an impedance of 75 Ohms and DMX cables used for light shows have an impedance of 110 Ohms.

The jury is still out on whether the "impedance" of the cable, which when we say it is 50 or 75 ohms for a single-ended cable (with RCA terminations) or 110 ohms for a balanced cable terminated in XLRs, should be added in, in calculating the ratio between the input and output impedance of two devices connected to each other by cable. Lanx is absolutely right to say that cables have "impedance", but when we use that term for cables, we are really referring to a quantity more properly called "characteristic impedance". Characteristic impedance is the square root of the cable inductance divided by its capacitance (L/C). We express this fraction in "ohms". By this definition, cables with high capacitance have low characteristic impedance. Obviously, if you just take an ohm meter and measure the resistance across any IC, it will be only a few ohms, which can be ignored in our calculation of the ratio of the input to output Z. It is or was my belief that characteristic impedance only becomes significant at frequencies way higher than the audio spectrum, e.g. at MegaHz or GigaHz frequencies OR if the cable is very long, much longer than what you are likely to be using. But maybe I am wrong. Maybe we will find out.

Pro-ject answered me that the impedance of the XLR output was of 100 Ohms. So assuming that the impedance of the cable itself is between 75 and 110 Ohms, we should be fine with a 1,66 kOmhs input impedance.

Regarding the way we should count the impedance of the cable in the system, I can't answer at all but I would be curious to learn if someone can help.