I heard about the wonders of a small device by Sonore called the microRendu, a product that takes an Ethernet audio stream from a computer or server and “renders it to a perfect, ultra-low noise USB feed to one’s USB DAC.” It purportedly boosts digital playback in terms of clarity and “musicality.” One of my audiophile friends who tinkers with his system regularly bought one and made it a permanent fixture. I had been using the Salk Audio StreamPlayer III, which is a server and also does the rendering, with success and did not really have a strong reason to upset the apple cart save for the fact that I know how it is with audio components. There is never an ultimate; there is always something to come along and improve performance.
I was thin on experience with server/streamer devices and it was time to push the boundaries a bit further in that respect. Catching the hubbub about such components I saw quite a bit of favorable comment about the Sonore products, so I decided to jump to the top of the line. The Signature Rendu SE is two rungs above the original microRendu and includes a premium built-in power supply.
To use the Signature Rendu SE, I needed an Ethernet streaming device. A company called Small Green Computer, which also sells the Sonore products, provided their sonicTransporter i7.
The Small Green Computer sonicTransporter line comes in a variety of configurations and price points, from the $697 microjukebox NAS/server to the sonicTransporter AP i7 4T (the abbreviations stand for Audiophile, Intel i7 core and 4 Terabyte storage).
The SGC sonicTransporter AP i7 4T (Roon Server)
This is where the files are stored and cached for playback. It is a computer built with attention to speed and capability for maximum performance in music related activity and this model is specifically optimized to support Roon DSP and other processor-intensive playback software, such as HQ Player. However, you are not required to run Roon with the sonicTransporter nor with the Sonore Rendu. Other options include Squeezelite, HQ Player, Squeezebox Server, and BubbleUPnP Server.
Here are some technical highlights of the SonicTransporter under review:
Intel Processor i7 – 4 core with 8GB RAM
128GB SSD for the Operating System
4TB Western Digital Red Pro Drive for music storage.
TEAC Ripping drive (best available)
All music play back is from cached Memory
For a more thorough look at the SonicTransporter:
Sonore Signature Rendu SE
Without regurgitating the entire litany of specifications, the Rendu SE is capable of frequency rates for PCM up to 768kHz and for DSD up to DSD512. To learn more of the minutia of the operation of the Rendu SE, I direct the reader to this web page on the Sonore site:
Getting the sonicTransporter and Rendu SE working together was the easiest of any computer-based digital source I have used. When the two components were connected to each other and to my network, all I had to do was go to my home computer on the same network and open the page http://sonicorbiter.com, where both units appear as “sonicTransporter Audiophile” and “Signature Rendu SE.” For either one, clicking on the associated “Manage” button (onscreen, not on the unit; there are no other buttons on the face of the units except for a CD eject button on the AP i7 4T) allows entrance to the Settings, where the proper server software can be selected. From that point the setup is automatic and upon opening the playback software the duo updates the system and readies to play!
Regarding my interaction with Simple Green and Sonore, I spoke mostly with Adrian Lebena, co-owner and designer of Sonore products (Jesus Rodriguez being the other co-owner of the company), in order to clarify installation of the safely shipped, mundane looking, but well-built blacked out components that arrived at my door. The instructions found in the box of the Rendu SE on a single instruction card, as well as online, are minimalist, but sufficient. The user is gently nudged to conduct setup and interface with the companies online. However, both Andrew and Adrian seemed at ease and content to assist by phone whenever needed.
In discussion of where the combo would be placed there was some concern raised by Adrian initially that a long run of Ethernet cable might interfere with proper operation of the Signature Rendu SE (hereafter Rendu SE). Sonore recommends establishing the Rendu SE as close to the source router as possible. My router is upstairs, quite a ways from the listening room. Out of necessity for the integrity of the signal I use an Ethernet over power line solution, and it has proven effective beyond my expectations for both dependability and quality. The systems I’ve set up using Ethernet signal over the power lines have exceeded the quality of older ones using a Mac Mini in the same room!
To my delight neither of the niggling problems thought to potentially appear with my setup so far from the home’s router happened. Even though approximately 100 feet of Ethernet cable snakes its way to the listening room (and that not custom wire) there were no dropouts. I did occasionally have dropouts with the Salk StreamPlayer III, which I had chalked up to lengthy signal transmission. It was a most pleasant surprise to discover that the Sonicorbiter and Rendu SE were bomb proof when it came to uninterrupted streaming playback. The long signal transmission was no longer suspected as the cause.
The other potential source of irritation mentioned by Adrian, prompting some customers to locate the sonicTransporter outside of their listening room, was a very, very faint whirring of the hard drive. In my custom listening room, with an ambient noise level of approximately 10 dB, I could hear the drive of the StreamPlayer III readily if no music was playing and I was still. The sonicTransporter seems to be slightly less noisy, and at no time did I find its operation to intrude upon my listening during quiet passages. I hasten to add that I do not listen extensively to chamber music, close microphone instrumentals, or classical music where silence is an integral part of the composition.
When all the pieces of the puzzle were in place – essentially, the sonicTransporter and Signature Rendu connected to each other and to the home network – they performed flawlessly in initiating music playback. A visit to the sonicorbiter.com website allowed my home Mac computer to recognize both the sonicTransporter and the Signature Rendu, and to ensure they were communicating properly.
Loading the music
Loading the music that had been on the StreamPlayer III was a bit trickier. When I switched over to the new equipment I lost the playlists that had existed on the StreamPlayer III. Andrew gave me adequate guidance via phone calls to make the transition, but I had mistakenly stored the backup on Roon to the StreamPlayer III. There is a possibility I can save those previous settings to an external drive plugged into the StreamPlayer III, then transition to the Sonicorbiter, add the external drive and recover the Roon settings and playlists. This is no fault of the equipment under review; it’s simply something to be aware of when transitioning to a new digital streamer/server. There may be complications; frankly, it’s one reason I delayed the transition. However, eventually the reward long term is so significant as to make those complications fade away once established.
A glitch that appeared seldom with the StreamPlayer III and Roon was a lock up of the software. Perhaps once a month while attempting to play a particular song, among them The Who’s “Eminence Front,” Roon simply froze. Nothing would dislodge it from the inability to load the song and play. The entire program had to be crashed and restarted. In fact, that was not enough to restore working order, because the StreamPlayer III also had to be restarted. An entire digital system reboot was necessary to get back to square one. This happened no less than five times over the months and it was usually with the same two or three songs, so I eventually stopped playing them. I do not know whether this was the fault of the StreamPlayer III or the Roon software, or an anomaly with the file residing at Tidal, the music source.
I have found no such malfunctions with the Sonicorbiter and Rendu SE. The pairing seems more capable of recovering from digital disasters, as there are several tracks with known damage on my Toto Tambu CD that were preserved in the files ripped and stored in my song database. Playing back the damaged files has been instructive, as the amount of time the server spent in “dropout” mode was less with the Sonicorbiter and Rendu SE than with the StreamPlayer III.
Sound quality differential between server/streamer components
This next section I presume objectivist listeners will disbelieve. So be it; I’m not out to argue ad nauseam what can or cannot be heard, but I simply report the experiences as they happen. If I have a technical answer as to why, I report it, and in many cases I do. However, there are some reasons for distinct performance differences that are not forthcoming, either because they are inscrutable or because the potential causes are too myriad for me to chase them all down and pinpoint.
I presume the second is the case in this instance, as, simply put, the combination of the Sonicorbiter and Signature Rendu SE has more high-end sensibility in playback of either file or streaming audio than the StreamPlayer III. Is this due to the isolation of function achievable with a two chassis product versus the integrated build of the StreamPlayer III? Perhaps; some of the most highly regarded digital sources made by top end companies separate function, primarily power supply, server and DAC into separate chassis, just as an integrated amp can be separated into two chassis as preamp and amp.
That is not a terribly satisfying answer, however. I suspect that a more satisfying answer is found in the power supply of the Rendu SE. Power supplies are critical to a component in allowing it to achieve ultimate performance. If you have a component that uses a “good enough” power supply, the component is not all that good – regardless of brand or reputation. How dare I say such a thing? When a person handles dozens and dozens of components across a wide spectrum, and every time an enhanced power supply is offered, or a custom build with an improved power supply is offered and the performance is markedly better, then the conclusion is clear, that stock power supplies usually fall short of premium sound.
Some try to go the external system power supply upgrade route, and many companies, some that manufacture cables as well, are willing to oblige. I find this a whitewash solution that paints all components the same coloration. I prefer to work with specialty power supplies for each component as opposed to broad-brush coat the entire system.
Setup for maximum playback quality using Roon
Roon itself offers several other options in the “Settings” menu bar, and one of the most critical for my achievement of the best sound was to turn off Roon’s Digital Engine entirely. I started by lowering, and then defeating the Headroom Management feature, but that only provided so much improvement. Turning off the Digital Engine provided another significant improvement. According to the Roon knowledge database the purpose of the 3 dB reduction is to prevent audio samples that exceed the allowed range and cause “clipping”, which it is said can produce audible distortion. In my experimentation the audible distortion happened well beyond the “0” setting and into the positive numeric settings such as “1”. I’m not suggesting that there is no digital music that may clip audibly due to defeating either the Headroom Management or turning off the Digital Engine, but I never heard any among my collection of artists. The result of both actions was vastly improved sound.
I will caution the reader once again; if one chooses to defeat either the Headroom Management or Digital Engine caution must be taken because if one is reckless with playback levels damage could occur to equipment. The -3dB reduction in the digital signal is significant and when it is eliminated the playback level jumps significantly! Do not mindlessly ramp up listening levels after defeating either the Headroom Management feature or the Digital Engine. There may be some among the audiophile population who prefer the sound of the signal with these engaged. I am not interested in debating my findings in this matter.
Another option in Roon is to tweak the frequency and bit rate of the playback, but since I had just finished the BorderPatrol DAC, which is an “NOS” design (non-oversampling), I started out with straight PCM or Redbook settings. However, even when using the Exogal Comet or Eastern Electric Minimax DSD DAC Supreme I found that the native signal as heard through Roon with the Digital Engine turned off was as appealing as any upconverted signal with it turned on. It seems that for all its functionality, there is a price to pay sonically for the tweaks available in Roon.