It seems that nobody mentioned i2s output, could I get out of the DigiOne?
Nope you cannot. Please use Kali for that.
Hi Johan, I could not find a detailed specifications and support documents for the DigiOne. For example, is it 192/24 max? Please let me know where to find it if I overlooked, Thx.
I will check the manual, but yes 24/192Khz tested.
I forgot to connect the terminating resistor.
No issues James. Lets see what the new (tested) Digione does to your system
My DAC supports both i2s and BNC input, do you think I should use Kali or DigiOne to get the best sound quality?
Hi Johan
We briefly discussed over PM but I was just wondering why a 50-ohm RCA connector was used and not the SPDIF 75-ohm standard for RCA?
Whether we can find true 75-ohm RCA connectors on 75-ohm cable is one thing but I would have thought to find the 75-ohm standard here to reduce impedance mismatches from the SPDIF standard.
I would expect most people to be using 75-ohm cable (the most common), but I could be wrong.
I would also expect most DACs to follow the SPDIF standard of 75-ohm RCA connectors.
Yes, I also know that it should be 75 ohm. According to this site, it is 75 ohm but hard to find one.
I did mention above that cables with 75 ohm connectors can be hard to find because I know about that BJC site.
But as I mentioned I would have thought youâd try to reduce the number of impedance mismatches.
But is the board connector (not cable connector) really hard to find at 75 ohm?
And it appears the HiFiBerry Digi cards conform to SPDIF 75 ohm standard but Iâll get confirmation:
While I donât think it will make an audible difference I wanted to know why the decision to select 50 ohm
And according to BJC:
the Canare RCA plug maintains the coaxial geometry through its entire length, and maintains a 75 ohm impedance as far as possible into the plug. While itâs inaccurate to call this a âtrue 75 ohmâ RCA plug, itâs accurate to say that no other plug on the market does such a good job of minimizing the effects of the impedance mismatch caused by the RCA plugâs unfortunate dimensions. The RCAPâs reliability, durability, high pull strength, and excellent spring-grip outer contact complete the package, making it, in our opinion, far and away the best RCA plug available
No RCA connector can be 75 ohm. Impedance is a part of cable geometry. The diameter of the center conductor and the distance to the outer shield will determine the impedance. The RCA connector has too wide a center conductor for the distance to the outer shield to come close to 75 ohm.
The âFâ type connector and some BNC connectors can be made in 75 ohm. They use very thin center conductors, compared to RCA.
The closest you can get is the design by WBT NextGen where the outer ring is not fully connected. That will then let the cable used determine the impedance. The WBT NextGen male connectors and the Eichman Bullet connectors are designed similarly.
Bottom line, if you want true 75 ohm impedance for digital, you would have to use BNC connectors on both ends of a 75 ohm cable.
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Yes thatâs the same as Blue Jeans Cable say above.
Hi Sean,
sorry for the late response , weekend
So if the RCA cables are really 50 ohm , its better to design with the true impedance in mind since beginning.
All good designers (DAC side ) they have 50Ohms terminations on the coaxial spidif as well since 75Ohm is simply impossible on cables. (except maybe that unique cable above)
Kali is a great choiceâŚbut to connect i2s to your DAC, it wont be so easy.
Really? 50Ohms terminations? That is new⌠I didnât know that. Someone should make a device (an SPDIF transmitter) that automatically optimises the transmission based on termination at the receiver end and reflections on the transmission line. The impedance is actually not relevant, the optimised transmission line is.
Yeh Iâve only seen SPDIF standard and SPDIF products mention 75-ohm. So it was strange to read that 50-ohm is a standard design.
I had thought it was best to aim for as close to 75ohm as possible too.
I bought a 75ohm cable to use with the rca output - belden coax with Canare âtrueâ 75 ohm RCAP connectors. How true to 75 ohm they are Iâm not sure as I donât have anything to measure with and a pro audio shop made it for me.
Im generally using the BNC>aes converted output and will probably disconnect the rca, but if known I wouldnât have worried about getting a cable made upâŚ
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Hi Johan,
Why is Kali is better one? it seems DigiOne is better based on spec.
Why is it not easy to connect i2s to my DAC? it is because of soldering?
Thanks