microRendu Measurements Thread

Amir’s measurements are about the effects of the combination of MicroRendu with the iFi – the point he makes is that the mR in fact passes the flaws of the power supply through to the DAC. That is a valid complaint – not a statement about the quality of the iFi, but a statement about the claims of the mR isolating the USB output from network and PSU noise. It is a valid complaint, in principle, if the measurements are correct.

I am not vouching for his measurements. I am rather unhappy about using the mR in DLNA mode, and using it with a DAC that misbehaves when used in “bit perfect” mode so he used “standard” mode, whatever that is. Anybody on that forum who cares about that kind of stuff will run things bit perfect, with RAAT or NAA, not DLNA. I’m not convinced to trust his measurements.

But the issue he raises is perfectly valid.

In fairness Sonore don’t claim the mR lowers the noise floor.

They claim

You can also combine the microRendu with an
audiophile grade linear power supply to
achieve the lowest possible noise floor

I think it’s fair to say the iFi is the standard power supply not an “Audiophile grade” one.

Hopefully there will be a few other tests done over on CA that will give us something to compare Amir’s results with, which seems to be the problem at the moment there is no other data available.

I don’t know whether CA are as positively biased as they claim Amir is negatively biased. Amir’s reluctance to try the test again using NAA or Roon as “he is too busy and has so many other projects on” strikes me as someone who rather likes the current set of results.

I really want the mR to be Valhalla so hopefully the hint by Chris on CA that he will get someone to run some tests comes to pass and we have more than one source of data about the mR.

SJB

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Hey, my first post here! As a Roon user, hopefully I am welcome here :).

Quick background: I ordered this device because there was so much hype around it improving audio fidelity. I did not hold a negative position per se against it. But rather, cautioned people that the ability of a digital in, digital out device to improve audio fidelity is very, very low when used with async USB DACs. The fact that it degraded performance with ifi Power supply (which has persisted from the first test result I showed) was a surprise to me. Clearly even the simplest measurements were not taken before they choose to sell the device with iFi power supply as a package.

Yes, I had history with both AQ Jitterbug and Regen also not performing as advertised (i.e. not improving and maybe slightly degrading). And make no claims to sainthood when it comes to such endeavours. But the last thing I want to happen is put out test results which get repeated by others and come out different. In the case of Jitterbug and Regen, my results were duplicated by others so history shows objectivity here, not bias.

The bottom line here is simple: if a device makes technical claims, then those claims should be demonstrated to be valid with measurements. Such statements as “reduced noise” are easily and trivially measured even with hobby gear. You don’t need the fancy equipment I have. That this is not done is disappointing. As consumers, we must raise the bar with respect to what claims are thrown at us. We have to be on each other’s side more than we are on the side of the manufacturer.

Anyway, I will be doing a hardware tear down and if stars align, test it with Roon and HQPlayer (currently are not: http://www.audiosciencereview.com/forum/index.php?threads/hqplayer-does-not-work.585/#post-17245).

I don’t think that is fair to say :slight_smile: Here is what the manufacturer says:

[quote]The central characteristic of iFi is in pursuit of the zenith in audio performance: it leaves no stone unturned. Well, the all new iPOWER is an exemplary example of this. Despite the fact that the iFi Ultra-Low Noise AC/DC adapter was exceptionally quiet and elevated the iUSB and iPhono to punch way beyond their respective categories, the all new iPower is even quieter, up to 10x quieter in fact.

What is it?

Brand new audiophile-standard DC-power supply:[/quote]

I am sure it is these types of marketing claims that enticed Sonore to bundle it with microRendu. And me to order it from them just the same.

It is only after my measurements show that this power supply with microRendu degrades the DAC performance that is causing is to not call it audiophile supply. This points to usefulness of objective measurements.

Amir (and welcome by the way), we all know audiophile products have to cost over $100, it’s mentioned in the UN convention of Musical Rights or some such.

Nonetheless I (and many others) will be interested in seeing any data you can produce for Roon > mR and Roon>HQP>mR.

Bring it on.

SJB

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Interesting point, and one that makes sense to me. Seems to me there are better ways to spend $600 to improve the sound of your system.

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You’re very welcome here and I’m looking forward to the discussion including measurements.

Clearly even the simplest measurements were not taken before they choose to sell the device with iFi power supply as a package.

You don’t know what tests the developers performed. No measurement can tell you that. Please try to avoid this kind of unwarranted conclusion as it lowers the quality of the discussion and reduces the prospects of a response from the developers.

I was surprised at how little switching power noise came through from your laptop. The whole point of using an Ethernet network endpoint is supposed to be to avoid the noisy computer environment, yet your measurements suggested it would be better to have a laptop next to the DAC than a specialised device. The only other laptop measurements I’m aware of were these ones by Archimago. He speculated that the increased noise for the Aspire may have arisen from increased processing.

I use a BRIX as a server for Roon and have avoided putting it next to my DAC because of concerns about power or processing noise. I initially ran a 5m USB to the DAC, later used a CuBox-i (switching supply) and now the mR (iFi) as NAA for Roon/HQP. It would be interesting to compare measurements of all four configurations.

Gianluca has suggested in the other forum that your playback problem with HQP may be because the internal audio device is busy. Are you running another audio program ?

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Hey Amir,

I found your blog via a link from the Roon community. I have bookmarked it and have enjoyed catching up on the topics you’ve covered.

Good luck from this Roon user and audio newbie. Looking forward to following your posts.

Tom

[Moderated]

Since you have stated that you feel the prospect of a digital I/O device improving sound quality is very very low… Can you please expound on and give us your view on software and it how it may or may not impact sound quality in this context also. Oh and BTW; since MR is an audio device designed for listening to music, have you bothered listening to it?

thank you

[quote=“Bob_Sherman, post:135, topic:8219”]
R is an audio device designed for listening to music
[/quote]it’s a microcomputer with ethernet input and USB output and some audio software loaded…as much an audio device as the next PC, except it claims to be better suited to audio application than other micro computing devices.

Correct. Architecturally it is a simple device. Its SOC (core CPU and system logic) is from freescale. It has a dual core ARM processor running at 1 Ghz! It has GPU for 3D operations, hardware video decoding, support for various copy protection systems, etc., etc. In short, it is a very high-end device for the functions that it is designed for. Single unit pricing for its CPU is $30! If I were to design something for audio, I would have opted for a much lower speed processor that would use less power, run cooler and have less potential for radiated signals.

I am puzzled why they thought they should use such a high powered platform given the target market and size of this device.

[Moderated]

If others are interested, I will write an article on ASR forum for it.

Well, I was going to do some of that testing but alas, as I reported earlier on ASR forum, the microRendu no longer recognizes my DACs. :frowning: I have tried everything and it just refuses to recognize the DAC.

Did you get yours and how does it sound to you?

Hi Tom. That is great to hear. And thank you very much. The forum is still new (started a couple of months ago) but I hope to keep growing it with technical articles and measurements.

Sorry, I assume everyone knows my history of testing of other products from John Swenson. He has produced another project, a USB device called the Regen. As here, I found through my measurements that it degraded performance when used as intended. And again like this round, usage of my lab supply cleaned up the problem. I then met with him and his sales person Alex and rocky mountain audio fest (RMAF). We spent a good hour together and during that time I realized that he doesn’t have any audio measurement tools. And that his day job is a digital designer in unrelated field so he did not have access to such equipment at work either.

Perhaps he now has such measurements and will post the results. Until then, my assumption is that no one would would measure this combo would recommend it for sale to audiophiles. A 30 db increase in mains noise and harmonics is no small matter.

Good USB DACs, even bus powered ones like the iFi DAC that I used, have post regulators that clean up the USB power. There is no reason or excuse for power supply noise to bleed into their output. And this is a low end DAC. I expect high-end audiophile USB DACs to be totally insensitive to such things. Please see the measurements of my Berkeley Alpha USB bridge driving my DAC here: http://www.audiosciencereview.com/forum/index.php?threads/high-performance-pc-server-interfaces-async-usb.8/

Those measurements were with my then Sony laptop driving the DAC. We see no evidence of the kind of noise that is present in microRendu. Performance is superb across the board. See this graph: http://www.audiosciencereview.com/forum/index.php?attachments/mark-levinson-502-hdmi-input-vs-berkeley-vs-audiophilleo-png.7/

I would immediately return any high-end USB DAC that is not immune to source/computer USB vagaries, noise, etc.

Indeed by using a low-end DAC here, I am giving these devices every chance to show that they can reduce noise. Yet what we see at best is no difference and at worse, degradation.

The marketing of audio tweaks has done a disservice to consumers by creating such worries and then selling products to fix them. They may be right but where are the measurements? Noise is trivial to measure. Why not demonstrate such facts? Where are all the measurements of laptops having noise injected into high-end DACs? I have not seen such.

What is your DAC? I would start with its measurements through its USB port. If it excellent, then I would not worry whatsoever about using it direct.

You should only use these devices if you need to put them far away from your computer server. Otherwise, you are buying yourself less reliability and extra expense.

This thread is for discussion about measurements relating to the microRendu. I have separated the discussion out from the microRendu General thread. I have moderated posts and parts of posts where they do not comply with the Forum guidelines or consist of discussion of such posts. I have indicated [Moderated] where I have moderated a part of a post, leaving the part that relates to audio discussion.

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Auralic Vega

I eventually intend to put my BRIX server further away from my stereo than it is now in order to isolate fan noise (comes on using closed form in HQP, which I like).

Also in addition to the DAC’s voltage regulation/supply, a lot of newer DACs employ XMOS chips or the like. These chips when properly deployed, completely isolate the power and noise on USB side of the DAC from the actual DAC and analogue circuitry on the output side, making the computer on the other end of the USB cable largely irrelevant.

Room Treatments?

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Absolutely!

Agreed. No kit upgrades and audiophoolery will get you as large an upgrade as a properly treated room or at least some DRC.

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