Sonore opticalRendu & Signature Rendu SE Optical Review | Part 2

On June 26, 2019 I wrote,

"Just when some are doubting the need or capability of D to D converters, Sonore releases the opticalRendu, Signature Rendu SE optical, and enables local storage on the platform. There isn't a single box solution available with the same level of performance, flexibility, and cutting edge features as the Rendus. In addition, there isn't a yearly, monthly, or lifetime fee associated with all this greatness from Sonore. As soon as my new speakers are installed I'll be listening through the noiseless optical network connection of the Signature Rendu SE optical and publishing an extensive review of its sound quality in a reference system. Stay tuned." (Part 1)

The time has come for me to stop listening and start writing about the Sonore Signature Rendu SE optical in my reference system. I don't want to stop listening. I'm writing this from my listening chair, with my feet up, and the volume at a nice -33 dB on an EMM Labs DV2 reference level DAC. Midnight Sugar from the Tsuyoshi Yamamoto Trio is playing through my Constellation Audio monoblocks and Wilson Audio Alexia Series 2 loudspeakers. It's truly delightful. 

Given that the technical details have been covered in my video and part 1 of this review, I'm sticking to the fun stuff this time around. I will note that the opticalRendu and Signature Rendu SE Optical I have are nearly identical. The "Signature" has a custom built-in power supply while the opticalRendu has a custom external power supply. The supplies are the same. The difference for the end user is s/he can use the all-in-one system of the Signature, or try different power supplies by going with the opticalRendu.

On With The Show

My reference system has been in place for a few months and my speakers were official setup by John Giolas from Wilson Audio about a month ago. The system has never sounded better and I've never had better sound in my house than I have currently. With that out of the way, let's dig into the performance of the Signature Rendu SE optical. 

We all agree that what's on a recording is 100% of the music we have a chance of hearing through our systems. It isn't 100% of the music usually, because the analog or digital capture probably left a little bit in the recording studio or live venue. Thus, we can only hope to reproduce 100% of what's on the recording. Audio equipment can do one of three things to a recording during playback, reduce this percentage from 100% to something less, add sonic color, or completely preserve it. Based on my extensive and critical listening through the Signature Rendu SE optical, I have no doubt this component completely preserves every last magical ounce of music. 

Over the last few weeks, I've spent a considerable amount of time comparing the Signature Rendu SE optical to different methods of sending music to DACs. The one absolutely major, can't miss, unmistakable performance aspect that the Signature Rendu SE optical brings to the table better than anything I've yet heard, is its ability to preserve transients. Yes, it preserves so much more than this, but its preservation of the attack, decay, sustain, and release of transients is otherworldly. 

Listening to the aforementioned Midnight Sugar album (Three Blind Mice / First Impression Music), this transient preservation is evident in spades. On the title track, Isoo Fukui's opening bass lines lumber forward and lay a foundation for Tsuyoshi Yamamoto to work his piano magic from about the 0:20 mark onward. The decay, sustain, and release of this first spattering of piano notes is just wonderful through the Signature Rendu SE optical, but it's the attacks starting at about 2:25 that really get me going. When Yamamoto presses each key, and the hammer subsequently strikes the string, it's a jarring yet beautiful start to some true melodic magic. It's as if he's telling the audience to listen up, then rewards them with terrific follow up notes with lush overtones that seem to decay for miles while giving away ambient details about the recording environment.

On track four, It Could Happen To You, everything is just right with this trio. Fukui's bass and Obara's drums are only there to support Yamamoto's brilliance on piano, and it comes through like a dessert for one's ears. There's a delicacy to Yamamoto's piano throughout this track, with subtle transient attacks and absolutely gorgeous decay, sustain, and release of the notes. The "SE optical" doesn't step on any of this enveloping sound that can transport the listening back to Tokyo in 1974. At roughly the two-minute mark of the track, Yamamoto plays a series of notes several times over. Each of these notes has a distinct and abrupt beginning with a lovely decay and glorious overtones that are pure pleasure for the ears. 

I want to stress the exceptional ability of the Signature Rendu SE optical, with respect to transients, one more time because it's so critical to realistic music reproduction. Nothing makes me lose interest faster or makes me more bored with my favorite music than equipment that rounds the edges of transients. Conversely, when components get transients right, like my previous all Spectral Audio system, it leads to a transcendent listing experience. Yes, the activity of listening becomes an experience that can bring about goosebumps, chills, and even emotions. 

To hammer this transient preservation home, let's tap on the Larry Karush recording titled May 24, 1976, available at 24 bit / 96 kHz for stream or purchase. Track one, [Untitled] is 3:17 of harmonic heroin. Right from the start, the fundamentals and overtones lay an eerie and beautiful path to the transient hammer strikes of Larry Karush. This is most evident from about 2:15 of the track until 2:42 when Karush starts a series of notes with violent hammer strikes that shoot up in frequency like the read-out of an electrocardiogram. The Signature Rendu SE Optical enabled both the dCS Rossini and EMM Labs DV2 DACs to reproduce these transients like nothing else I've heard in any of my systems over the years. The leading edge of the transient appears to shoot up like the face of El Capitan, then trail off as the overtones played out in beautiful fashion. 

In addition to transient preservation, the Signature Rendu SE Optical preserves all the musical information without adding any secret sauce to flavor its output. This enabled the reference level DACs to which I connected it, to shine in ways I haven't heard surpassed. I did so many A/B listening sessions that my head spun like Regan in The Exorcist. I know what I heard over and over again as I tried different music and different interfaces on these DACs. I just had to be absolutely positive that the results were repeatable 100% of the time. I can unequivocally state that the differences I heard between the output of the Signature Rendu SE Optical flowing to USB inputs versus AES inputs and Ethernet inputs, were pronounced and the "SE optical" was as good or better in almost every way. 

Note: My comparisons with the Aurender W20SE weren't thorough as I'd just received it for evaluation. But, there were some nuances in tone that I heard via the W20SE and not the "SE optical."

When I switch to Ethernet and AES inputs I obviously had to use different sources because the "SE optical" only has a USB output. Thus, the sonic differences can't be pinned 100% to the Sonore component. However, given the real-world scenario of selecting a source component based on how it sounds with one's DAC, I have no issues with attributing my findings to the Signature Rendu SE Optical. For example, using Roon to send audio to the dCS Rossini's Ethernet interface versus using Roon to send audio to the "SE optical" that sends it on to the Rossini's USB interface, I'm 100% positive the path through the Sonore component is much better. This source selection is a real-world decision people will make, should they use Roon directly or through an optical Rendu? Sure, this can be sliced every which way, but in this real-world situation, I haven't heard anything deliver audio to the Rossini better. 

I mentioned music and emotion a bit earlier. Note, Song and Emotion is a great track from Tesla's 1991 release Psychotic Supper. Anyway, music's ability to bring out emotion and suck listeners in is uncanny. When an audio system gets everything right, this can lead to experiences one never forgets. This is exactly what happened to me a couple of weeks ago, listening to Bob Seger's Greatest Hits. I know, of all albums, Bob Seger's Greatest Hits is the one that gave me chills, sent me back to the 1970s in a time machine, and pushed me to keep listening until the wee hours of the morning. I have no attachment to Bob Seger's music as I didn't really listen to it back in the day, but dang it sure was special the other night, through the same audio system as used previously.

Bob Seger's Turn The Page is a classic track that doesn't even rank on any audiophile approved music list. Instead, it's about the story, the way Seger weaves it through his lyrics, and the way he delivers it with a sense of authenticity. Through the "SE optical" I immediately established a vision in my head of Seger's tour bus rides, the restaurant into which he walks, and Cobo Hall in 1975 with him on stage. I was simultaneously in my listening room and on a long leg of a North American tour with the Silver Bullet Band. 

The track is recorded live but it certainly sounds much more intimate than the 12,000 seat Cobo Hall (now TCF Center) on Washington Boulevard in Detroit. Right from the unmistakable opening saxophone melody, I connected with Seger's story. His vocals had this realness to them, not Maria Callas style with impeccable range and precision, but as if the guy next door grabbed a microphone and walked me through the last few months of his life. My audio system brought me closer than I've ever been to Seger's voice. I was captivated. I listened to the entire album several times over without a break. The entire time, I never lost the sense of closeness with the performers and the performance. OK, I skipped over "Old Time Rock & Roll" because I can't get the image of Tom Cruise dancing in Risky Business out of my head. I think that's called a buzz kill in certain circles. 

On Night Moves, the opening acoustic guitar sounded nothing like that on a Reference Recordings release and Seger's was in the same less than audiophile category. But, given what I heard, I'd take this experience 100% of the time over something recorded pristinely at the highest resolution available. This Redbook 16/44.1 track, with goosebump inducing backing vocalists, was absolutely perfect. 

I recently thought about that evening, trying to figure out why I was so moved and how to repeat this experience. How to listen to music which I'm not attached and have no real emotional connection from my youth, yet have a transcendent experience listening to it. I believe it was the perfect music being played effortlessly through a great system that was fed from a transparent source that didn't change what Bob Seger delivered and his recording engineer captured back in 1975. This was a remarkable audio experience I will never forget.

Conclusion

The Sonore Signature Rendu SE optical is quite a component. It delivers everything one could want to an audio system. That's its role. Don't change anything, don't add anything, just make sure that what's on the recording is delivered to one's DAC of choice pristinely. The "SE optical" is in an enviable position in that it's a component capable of improving almost every audio system. I say that because it improved every level of the system to which I connected it over the last few months. I consider its improvement in my reference level system to be indicative of its highest achievements. 

One aspect of music that makes or breaks the illusion of reality and live performances in our listening rooms is transient attack, decay, sustain, and release. This is what real-life sounds like. A real hammer strike from a piano doesn't have a rounded edge, and it doesn't when played through the Signature Rendu SE optical. Compared to Ethernet and AES inputs on reference level components, the "SE optical" delivering audio to their USB inputs sounded better. Plain and simple. That's not a knock on the DACs, it's a huge compliment to the Sonore team for delivering perfect audio to and improving performance of some of the biggest hitters in HiFi.

If the "SE optical" can make a dCS, EMM Labs, and Berkeley Audio Design DACs perform at an even higher level, I'd say the future is bright for almost anything to which it's connected. Right now we have a leader in the clubhouse for Audiophile Style 2019 Product of the Year. 
 

Product Information:

• Product:  Sonore Signature Rendu SE optical ($3,445)
• 

Associated Music:

• Qobuz AXPONA 2019
• Computer Audiophile 100 Playlist
• Computer Audiophile PJ4CA Playlist

Associated Equipment:

• Source: Roon ROCK, 2018 MacBook Pro Running Roon, JRiver (Windows 10 and macOS Mojave)
• DAC: dCS Rossini, EMM Labs DV2
• D-to-D Converter: Sonore Signature Rendu SE (optical), APL HiFi DNP-SR
• Amplifiers: Constellation Audio Mono 1.0 / Monoblock Power Amplifiers
• Preamplifier: Constellation Audio PreAmp 1.0
• Loudspeakers: Wilson Audio Alexia Series 2
• Remote Control Software: Roon Remote, JRemote, Aurender Conductor
• Remote Control Hardware: iPad Pro
• Playback Software: Roon, JRiver, 
• Network Attached Storage (NAS): Synology DS1812+, CAPS v4 Cortes Server
• Audio Cables: Transparent Audio Reference Interconnects (XLR & RCA), Transparent Audio Reference 110-Ohm AES/EBU Digital Link, Transparent Audio Reference Speaker Cables
• USB Cables: Transparent Audio Premium USB Cable
• Power Cables: Transparent Audio Reference Power Cables
• Power Isolation: Transparent Audio Reference Power Isolator
• Ethernet Cables: Transparent Audio High Performance Ethernet Cables
• Acoustic Room Treatments: Vicoustic Diffusion and Absorption,  ATS Acoustics Bass Traps
• Network: Ubiquiti UniFi Switch 24, Ubiquiti UniFi Switch 8-150W x2, Ubiquiti UniFi Security Gateway Pro 4, Ubiquiti UniFi AP HD x2, Ubiquiti FC-SM-300 Fiber Optic Cable x2, UF-SM-1G-S Fiber Optic Modules x4, Calix 716GE-I Optical Network Terminal, CenturyLink 1 Gbps download / upload