MicroRendu, UltraRendu or Other

From that link:

" Objective measurements of analogue output from my DAC using the optical USB cable shows no difference compared to a shielded 10’ USB 2 wire cable.** **Likewise, no difference in the J-Test FFT to suggest audible jitter anomaly at 16-bit/44kHz or 24-bit/48kHz"

Two paragraphs higher: “Indeed, the analogue noise can be transmitted down cables like the USB cable and cause audible interference. I demonstrated how the Corning Optical USB cable can be used to minimize the noise originating from the computer. It’s logical. It can be measured. No magic.”

1 Like


The ultraRendu has far less circuitry than the RPi units. The RPi is a scaled down general purpose computer that makes lots of electrical noise. The components are so close together that EMI is an issue so even with all the cleanup that Also does, there is still more noise than with the ultraRendu. I’ve tried all this stuff as I wanted a cheaper endpoint…it’s just putting lipstick on a pig. It’s better but it is still a pig.

(post withdrawn by author, will be automatically deleted in 24 hours unless flagged)

1 Like

Both the Sonore and Allo products referred to above are excellent. I use a microRendu in my main rig and a DigiOne in a second system at my partner’s house.

Unfortunately I haven’t done a direct comparison in a way that would enable me to sensibly recommend one over the other and I haven’t had any experience with an ultraRendu.

One bit of gear that did make a difference in my microRendu system was the UltraCap LPS-1.2. This definitely increased the dynamics in my system. Would another less expensive LPS have done the same ? I can’t say.

Edit: One thing I would say about the price differential between a second hand microRendu and a new ultraRendu is that spending that money on a room treatment wav to convolve in Roon is likely to make a bigger impact.


This should be everyone’s take-home. There are no bad choices here. Plus, in all likelihood (and this coming from someone who’s happy to use such devices rather than a Pi), a bit is a bit, anyway.

and that, too… 3… 2… 1… “Dirac, or better yet, Trinnov, add-on for Roon !!!” :wink:


I’ve had an ultraRendu in my system for nearly a year, feeding the DAC in a Hegel H190, with Roon core running on a Mac mini. It cost me about 1,000 Canadian pesos (with sBooster PS). It works flawlessly. It sounds great. I’m very happy with it, especially having faffed around with DNLA, UpNP etc., as all I have to do is switch to Roon on my MacBook Pro where the controller is and turn the amp on. Haven’t had a chance to A/B with a similar product like Allo’s offerings, which by all accounts are also excellent, but it definitely sounds better than the Mac mini directly feeding the Hegel. In fact, the Roon Ready implementation from Hegel (whenever it arrives) is going to have to be pretty darned good to make me switch. You’d be happy with either Allo or Sonore offerings I’m sure.


Thanks for everyone’s input. I am curious if anyone has experience with the Bluesound Node 2 or 2i and should I consider as a possible solution.

Thank you

Am I right in thinking that Daniel has used these @Rugby ?

I have used the DigiOne, not the signature version, and I love that. I have tried the Sonore products and while I like them, I really didn’t have a use for them so I passed them on to other friends. If I had a situation where I needed one, I’d have no hesitation picking one up.

I have the Bluesound Node 2i and more recently added an ultraRendu (with UltraCap LPS-1).The Node 2i has a few functional advantages (such as support for integrating a hand-held IR remote, a greater variety of input/output options, and physical volume/tracking controls atop the device.) It’s a relatively user-friendly device.

For me, probably the most important thing the uR brings to the table is support for network operation of HQ Player. If you are not interested in HQ Player, then I’d hesitate to recommend the uR over the Node 2i solely on the basis of SQ. The uR (by itself) may or may not deliver a noticeable enough difference in SQ over the Node 2i (for you, in your system) to justify the additional cost. To know for sure, I think you’d need to try out both, then keep the one you prefer and return the other.

I know a lot about the pi processor board. I’m not against using it, but we looked at it and it can’t meet the goals we set forth for our products. I won’t get into why the pi board is inadequate for our needs because what we are doing in the Rendu series is proprietary. Hint, we are closely interfacing with the SolidRun module in a way that you can’t do with a pi board. The SolidRun module we use looks similar to the standard offering but it’s a custom order so your analysis is wrong. BTW we have our own processor board design, but it costs a lot of money to reproduce and it’s really not worth it for us to produce it because SolidRun has a firm handle on that.

FYI Some companies say ground up design but they are actually using reference designs made available to anyone so best to avoid assumption. Also, SotM claims to have made the operating system, but I know where they got it from…us:)

These are computers with USB output streaming bit perfect audio so irrelevant graphs showing nothing useful are pointless. I think’s it’s inappropriate for you to suggest we don’t have an incredible product with fantastic support and fantastic customer engagement. We are a small company in a niche market and we tailor to our customers. We have products at various prices with and without power suppiles.

By all means recommend Allo, SOtM, pi, or anything else for that matter, but please avoid comparing things incorrectly.


Tom, the UltraCap LPS-1 has a lot of noise on it’s output. The UltraCap’s charger was less noisy when I last measured it;) If you want to improve things you need a better power supply. At minimum you should implement a trick that John came up with to reduce the output noise from the LPS-1 which is to shunt the DC negative of the charger to AC ground. You can find more information on this technique here:

I thought the UltraCap LPS-1 came highly recommended. Now I’m confused. It has (or had?) a lot of noise, but now is less noisy? These are not inexpensive products. I’m not too inclined to mess around with the grounding.

@Jesus_Rodriguez, did you mean to say that SMPS are noisy ? The cited article by John details his experiments in suppressing leakage current from SMPS and concludes:

If you want to get it all you will have to use something like the LPS-1 which will get rid of it all.

The UltraCap LPS-1 was replaced with the UltraCap LPS-1.2. The UltraCap LPS-1.2 is an updated design and it also has the grounding trick built into the SMPS.

Both are noisy. The combined update and grounding trick on the LPS-1.2 makes for a cleaner power supply. Personally, I prefer a linear supply.

1 Like

So was John wrong in the cited article when he said the LPS-1 eliminated all such leakage current ?

I thought the design of the LPS-1 rendered the charging device completely irrelevant because there was never a connection between the charging device and the capacitor bank supplying power.

John identifies two forms of leakage current. The combination of the trick and the update design improves things.

I am more confused now. What I bought (to power the ultraRendu) is the LPS-1.2. Isn’t “LPS” an acronym for “linear power supply”?