Impact of a DDC using SPDIF (not I2S)

@rikkipuu Thanks, I will take a look at the Rendu gear. 

I have a Statement.  I found using an Antipodes S20/S60 to output S/PDIF (BNC) is a benefit even with the Statements excellent USB, so higher quality sources also benefit.

FWIW I also found the Ethernet output of the Statement to be better than USB.  I use an OpticalModule/Signature Rendu Deluxe to change Ethernet to USB and then to the Antipodes.

I can't say enough how blown away I was when I added the Signature Rendu Deluxe,  I think it has been the single most profound upgrade I have made.  Its more than just the Optical as I used an UltraRendu/OpticalModule combo before the Signature Rendu Deluxe.

Thank you for all the replies, this is very helpful. What I am hearing is that a DDC is most effective when the source is lower quality or if there is a genuine need to convert or split the signal to different formats. Given that I have a well regarded source in the Innuos Zenith and a very decent DAC in the Merason, I think that I will put this idea on the shelf for now. Thanks again for your input!

My findings with my Hermes is that there is slight improvements to soundstage size, depth and better bass definition. I've had it since March of 2022. I use 3 inputs, so that is convenient.

I2S is always better sounding 

I bought the top Wireworld  hdmi and it sounds great 

my wife has the Denafrip Iris  ddc and it really cleans up, the noise and cleans up 

the signal .

@fuzztone - Denafrips (or their former dealer) youtube videos actually clearly state that DDC effect depends on the source. If source is already good, there may be no effect - like there is no reason to chain 5 DDCs, right?

DDCs are designed to convert outputs. If there is any sonic upgrade, existing components could only be lacking. Mine contributes no "improvement."

Denafrips actually recommends using DAC clock and Hermes can operate on Terminator (DAC) clock - this is my setup. I think DDC effect depends on quality of USB source. You may get biggest value if source is a PC which tend to be noisy. On the other hand, if the source is already good, reclocking again may or may not bring any benefits. 

My first DDC was the Hermes. I tried it on a whim, did not perceive a sonic improvement, and eventually sold it. After going a year without using a DDC, I changed some things in my system, added a Sonore Signature Rendu SE optical streamer which only has a USB output, and decided to try another DDC, mostly to have additional connection options.

I am now using a Singxer SU-6 connected to my Sig Rendu SE streamer by a short USB cable and am currently running three different DACs connected to it by AES/EBU, S/PDIF, and toslink/optical. In each case, I do not discern any loss of performance by having the DDC in the path. Using the DDC is also a great way to compare different inputs going into the same DAC since you can literally have them all connected at the same time.  The SU-6 has operated without a glitch in the 6 months or so since I have owned it.

I believe you are correct about inputs being "component dependent." None of the DACs currently in my main system have an I2S connection but I previously used I2S with Metrum’s Pavane and Adagio DACs. I didn’t hear much if any difference between I2S and the other digital inputs. I suspect the most significant sonic difference would occur between using a USB input, where the DAC’s clock does the work, and S/PDIF or AES/EBU inputs.

As discussed in the linked Singxer SU-6 review, there are likely jitter improvements associated with using a DDC, but whether those will be audible will probably depend on your system.

Although I use the i2S connection from my Iris and have gotten significant improvements from it, I gotta believe the clock and noise reduction/galvanic isolation are also providing a good amount of the benefit I’m hearing.  Here’s a Hermes at a nice discount, and I think the seller offers a 30-day return policy so well worth a look I’d think.

https://tmraudio.com/components/d-a-converters/denafrips-hermes-ddc-d-d-converter-2/