Phono Box DS3 B output impedance

AI says 200 ohms for xlr and 50 ohms for rca.  Write an email to Pro-ject for confirmation if you want to be sure.  So as long as the preamp xlr has 2k input imp. or higher you should be good to go otherwise use rca.

Lanx, The OP wrote above that he is driving a 1.66K input impedance. And I think that's no problem, even if the output impedance is 200 ohms.

@lewm I can raise it a bit for 6.7Vrms / 2.46kΩ input impedance but then the dynamic range is less satisfactory. So if output impedance is low enough, I would rather keep the 4,5 Vrms / 1,66 kOhms setting. I'm trying to figure out if the ratio of output Z to input Z is about 1:10 as you have guessed.

I emailed Pro-ject first but they read my email too quickly and sent a specs sheet without the information I needed. Will try again on Monday!

I am not sure why you prefer Pro-ject phono box over other brands. The xlr output imp on Schiit Skoll is only 10 ohms. Fully discrete, true balanced output and more dynamic. The SINAD from the 3rd party (asr) rated 78 for DS3 but 81 for Skoll.

Oh, you save a bunch of green.

1.66K divided by 200 = ~8/1, so not quite 10/1, but the difference is trivial. There is nothing magic about the 10X rule of thumb.

The fraction of signal voltage transferred is defined by the fraction Zi/Zo+Zi. When the ratio of output to input Z is 1/10, that fraction says 92% of signal voltage is available to the driven device. When it’s a ratio of 1/8, about 89% of the signal voltage is transferred. No big deal.