USB vs I2S Input to DAC

I am setting up an endpoint. I have either ethernet or wifi to endpoint. Considering 2 options for ethernet/wifi to USB connection to DAC:

1- Raspberry Pi wifi to USB output to DAC (understand ethernet connection to RPI would provide to much noise to the USB output).

2- Sonore Rendu (ethernet to USB) to DAC. Assume this will have better sound than option (1) above.

When doing research on a DAC I was considering (Topping D-70) it recommended using the I2S input since it sounded better than USB.

Does anyone have experience if USB or I2S input to DAC sounds better?

Any thoughts would be greatly appreciated.


I use both. It’s too close for me to say I2s is better, although it’s supposed to be. If you have I2s available, use it, but I wouldn’t buy something just to get I2s.

I did purchase a converter, a Sonore Ultradigital, but I also use it to split the USB out signal from my microrendu to I2s and SPDIF. This feeds two input devices.

Robert- Thanks so much for your input. It is extremely helpful. I had thought about the Ultradigital. So glad to hear from someone who had used both.

Found a convert you could use with Raspberry Pi. It was called Ian FIFO. It was a board you can add to the RPi for about $140 and give you an I2S output.

Thanks again for your help.


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Robert do you like the Micorendu? Is it is good as all the reviews? Consider purchasing the the original rendu.

Thanks for your kind help.


It’s a great device. I was an original adopter. If you plan on purchasing one new, this is where I would buy it. They also have premium options like the UltraRendu and OpticalRendu. Andrew Gillis @agillis owns small green computer. He is on the Roon site and will offer assistance if you need it.

You will need a power supply with it. The ifi Power device works fine ($50).


Thank you very much for he information. You have been extremely helpful. Thanks



I use both and have decided to abandon USB in favour of other means of connecting a to b. The reason was USB can be made to sound different quite easily, hence the popularity and range of ‘fixes’ for its perceived issues. I have used an AudioByte Black Dragon, PS Audio NuWave DSD, and most recently the afore mentioned Topping D70. USB into the D70 isn’t at all bad, but some effort finding an i2S LVDS source pays dividends IMO. So now to disagree with the MicroRendu as a recommendation. The 1.3 hw model makes a D70 sound flat to me. It is quiet, and the bass can be extraordinary but it sounds to me like the music is straight jacketed. And after you have spent accordingly to extract best performance guess what. A microRendu, LPS-1 or 1.2 and your D70 collectively come to more than the U.K. price of something like a Teac NT-505! So certainly, for me with exchange rates as they are and the opportunity to exchange several boxes and associated power supplies for one box, the NT-505 was something of a revelation.

Have you considered the Toneboard DAC by Khadas? It’s available for $99USD. It can be used as a standalone DAC using USB Type C, or with their optional SBC using a network connection. The DAC is a real winner and VALUE at $99. It sounds very good. Details can be found here.

The khadas SBC is not able to run roon bridge tho iirc. The Tone board is quite good but the usb-c is physical but needs to connect to a usb-a output, I’ve tried both my KTB’s and neither run directly usb-c direct

I run many dacs direct off of RPi 3B’s usb connected via LAN and no issues, some running source material upsampled even to DSD512. Cheap enough to try for sure. Ropieee Is highly recommend for the OS

I have 2 of Ian Canada’s I2S boards but never got them running - maybe a challenge unless you are right into Diy (which I am) but still gave up maybe too fast.

Wizard of Oz- Thanks for your input. You said you connect via your LAN. Is that direct with ethernet to RPi or via Wi-FI? Understand you might get noise via ethernet and better via wi-fi. What would you recommend? You seem like a great resource. Thanks for your kind help. I corresponded with Ian and either he is busy or cold. Basically I will sale you equipment but do not bother me with the details of your issues. Hope you get the boards working one of these days. Greg

Richard. Thanks for info on Toneboard. Greg

Wizard of Oz- Another question. I was thinking either using a Chromecast Audio (disk) or Raspberry Pi as an endpoint for Roon. I am assuming that I would get better sound quality out of the Raspberry Pi since I would use the USB into DAC versus Chromecast Audio using an optical in to DAC. If you do not mind when I decide on a path I might run it by you first since I new to this area of equipment. Greg

Wired lan…CC is limited to max data rates of 24/96 iirc

Happy to offer any guidance as will others no doubt.

Ian is a talented cat and like many engineers is not great with public facing things :slight_smile: I haven’t put much effort into the I2S boards as I have happily working systems.

wizard of oz- thanks for your willing to help.

I am considering Roon (do you have Roon and what do you think of Roon?) for my home audio system. Considering adding Roon to my audio system) endpoint in my basement. Have ethernet or wifi connection available. Also would like to have a headphone amp and be able to use use regular audio system in conjunction with the endpoint. Have consider the following:

1- Ethernet to RPi to USB out to Pro-Ject Pre Box S2 USB input. Have read that there might be a issue with noise using ethernet to USB on RPi. Others have used wifi to RPi and USB out to dac. What would you recommend? Also should i consider a RPi “hat” that has USB out for better sound? Also have seen mixed reviews and experiences with forum members regarding Project S2.

2- Same as above except using SMSL M500 (new DAC from China) which seems to be similar to S2 above. Have not been able to find reviews or user comments on the SMSL M500.

  1. Consider ethernet to Sonore MicroRendu to USB out to Topping D70 DAC (good reviews and user comments on the D70 DAC). However, one of the forum members said he had tried this setup and did not like the sound.

  2. When reading reviews on the Topping D70 DAC they said better sound from the IS2 DAC input. That is where the interest in the Ian’s RPi “IS2 to HAT” came from. Have decided this is beyond my level at expertise at this point.

  3. To use a Chromecast Audio disc has endpoint with optical out going to the DAC out. However, understand that is might not be the best sound quality.

Hope you do not mind me asking your help and suggestions regarding the above.



I’ve been using roon for 3+ years…love it.

I prefer lan wired connections and have no issues with audio disturbances for want of a better word. You could try the micro or ultrarendu too instead of the rpi, but if you have the rpi now then start with that.

I would go with usb if you can at first…more universally supported.

I’m not familiar with the topping products but they seem popular.

Chromecast (CC) audio is probably at the bottom of the quality stack imho but fine for a kitchen or basement setup maybe. I have a couple of of them and a few CC ultra 4K using hdmi just for fun, but most of my dacs are usb via RPi and ropieee.

Some of the better HAT based dacs have headphone outputs too, but only 3.5mm normally and limited drive so a hard to drive headphone might not do well.

You need to think about your roon core machine too…for a trial is perhaps better to use a faster machine as initial setup and music importing and analysis can be heavy on cpu use.

Henry- thanks for the info. Greatly appreciated.

Disappointed to about the use of the MicroRendu with D70. It is good to know about the sound from this combo before putting out the money for the 2 pcs of equipment. In the USA recently I saw the D70 for $420 (off now but assume it will be on sale again before Christmas) and the MicroRendu (original unit) B stock is $430 plus if power supply ($50). So could get setup for around $900. I setup $1000 for a budget.

The Teac NT-505 looks like great alternative as a all one solution. However, it is above my budget (at this point). Appreciate your bringing this unit to my attention. On wish list but hard to justify at this point.

Thanks again for your help. It is greatly appreciated.

You can look at the IQAudIO dac hats - some have amp board options too so can directly connect a pair of speakers…I use this in a couple of rooms for sound from roon and have a display on one showing tracks info and a clock when sleeping.

There are plenty of options here!

I use a RPi 3B+, connected over WiFi, to drive a DAC via USB. Works like a champ. If I wanted to use Ethernet instead, I’d use a RPi 4 instead of the 3, as it removes the issue with the Ethernet-USB competition.

I’d also recommend that you don’t worry too much about what someone else said about the sound of whatever you decide on. I suspect you’ll get great sound from any of your five options.

Im using mod. singxer f1 with r2r dac modules, no output stages, powered by hpuln lt3045 modules 4 pcs, 8 rail, singxer clock separately powered, dac as well,short signal cable max 5cm, and everything just so amazing.