Sonore opticalRendu

@thyname “as fiber transmission is just light, no electrical signal.”
As I said, it’s just 0s and 1s.

You can do anything you want, but that doesn’t make it better. Using the same supply means you are sharing the ground and thus the inherent galvanic isolation of the connection is lost.

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You haven’t read John’s white paper. It’s posted above someplace


The HD Plex claims separate rails and no shared ground.
The circuit for the separate rails are posted on the site.

That doesn’t tell me everything I would like to know.

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thanks for the reply but let me ask the question again without using the word “clock” as my question is about how the opticalRendu interacts with RAAT.

[transport + ROCK] --> usb cable --> [t+a dac 8 dsd]

[transport + ROCK] --> fiber --> [opticalRendu] --> usb cable --> [t+a dac 8 dsd]

in the before configuration, RAAT functions such that the DAC pulls the data from roon player running on the transport according to its (the DAC’s) internally generated timing.

in the after configuration, an opticalRendu is inserted into the signal path. my question is simply: will the opticalRendu in any way change how RAAT delivers the signal to my DAC in comparison to the before configuration? stated another way, is the opticalRendu simply passing through the signal making the after configuration functionally identical to the before configuration in terms of RAAT?


quick implementation question: is it possible to assign the opticalRendu a static IP address?

If you have the DAC connected directly to the Core, as in your “before” setup, Roon is not using RAAT as nothing is going over Ethernet. So of course things are different in your after scenario because it uses RAAT and talks to a Roon endpoint.

Basically, Roon streams the data to the Rendu and the Rendu buffers that data for playback to your DAC. If your DAC is asynchronous it pulls the data based on it’s internal clock. This process is also bit perfect.

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thanks for the information and clarification!!

from this KB article describing RAAT, this is not my understanding of how RAAT works.

It enables you to play your Roon music to:

  • Roon Ready hardware devices
  • Audio outputs, sound cards, and USB DACs connected to the Core.
  • Audio outputs, sound cards, and USB DACs connected to any computer or device running Roon Bridge
  • Audio outputs and USB DACs connected to Android devices running Roon Remote.

RAAT is a network protocol. USB ports on DACs don’t know anything about Roon or RAAT. They use standard USB audio protocols so that is what Roon MUST use to communicate with USB DACs.

thanks for helping out here… but i am having a hard time reconciling this statement with roon’s documentation. another article: What audio outputs or devices are supported by Roon? – from the faq page in roon KB. this clearly states that directly connected devices including usb dacs use RAAT for playback.

FAQ: What audio outputs or devices are supported by Roon?

Connected Outputs: Built-in outputs, USB DACs, and Sound Cards

Any audio devices recognized by the OS will be recognized by Roon, from Built-in Sound to PCI Soundcards to USB DACs.

In the settings of Roon, you will select which recognized audio devices you would like to display as Zones in Roon. Any Zone can also be configured to support Exclusive (bit-perfect) mode.

Playback to these devices uses Roon’s RAAT technology, and can be grouped with each other or other RAAT-based zones for multi-zone playback.

also, the before configuration is what i have implemented. here, a computer running ROCK and also used for the roon core is connected directly to the dac using a usb cable. the resulting signal path also indicates RAAT is used in transporting the audio stream:

…what am i missing?

We are getting off topic here. This might be a better discussed in a general forum section.

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just trying to fully understand how an opticalRendu would work in my system. your confirmation that it preserves asynchronous playback in my dac, presumably via RATT, is an important characteristic, along with optical isolation.

i think i understand this fully now. thanks for the help!!

An alternative is to use USB-C - DC 21.5mm cables connected to a USB-C Power Bank (like a RavPower) and feed the optical box closest to the Rendu with this.

Ghent Audio just posted these cables on Ebay after I requested them to make some for me.

Ebay ID: 223570527288

Would it still be worth keeping a USB re-clocking device like the W4S Recovery USB reclocker just before DAC after the OpticalRendu?
Or would the extra device with another linear power supply in the chain after “optical isolation” just be adding more bad than doing good at this point?

We generally don’t recommend adding anything between the Rendu and the USB device.

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Thanks Jesus for the advice.
That’s actually good news, and if I put the opticalRendu just behind my DAC I can connect them both directly with a very short 30cm ish curious cables usb I already have, shorter has to be better surely

RAAT as already mentioned is how audio is transported from core to endpoint over network not USB, USB does not understand RAAT it can only use USB Audio protocol. So in this setting its RAAT from.core to Rendu then USB Audio Protocol to DAC. Only DACs with ethernet connections receive RAAT and are classed as Roon Ready DACs. USB DACs are only Roon tested which means they work with Roon to full capabilities. Roon Ready means it uses RAAT.

Hi guys. Recently got the optical Rendu and it sounds amazing. I have a custom built power supply (built by Kenneth Lau) to power it. It’s a 7.5 v supply. I’ve heard it’s normal for the Rendu to run warm. Not too hot to touch but warm. I’m assuming this is normal. Just want reassurance as it really sounds wonderful.


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