Marantz SA-KI Ruby, My Reference DAC

Music tells a story, and hi-fi equipment brings that story to life. Sometimes, an individual piece of equipment has its own story to tell. The Marantz SA-KI Ruby celebrates the story of Ken Ishiwata’s 40-year career as Marantz’s premier engineer and brand ambassador.

Today, I’d like to tell you my story of how I took a leap of faith on this piece of equipment that I’d never heard or seen, and how I was pleasantly surprised by what I found. The Marantz SA-KI Ruby is now my reference DAC.

What do I mean by “reference”, anyway? The ability to consider a component to be a reference can be a long journey through music and sound. An audiophile identifies a reference component only through broadening his or her perspectives, and experiencing a multitude of different equipment to determine what’s valuable and what’s hype.

Finding a Reference Component

My reference journey started in late 2018 when I read Marantz’s press release about the new KI Signature Ruby integrated amplifier and SACD player/DAC, commemorating Ken Ishiwata’s 40^th year with the company. These units were to be a limited-edition production run with only 1,000 of each being released in the European market. As I would find out from Mr. Ishiwata himself, there would be even fewer units in North America.

Of course, I had questions. Were these just pretty boxes with an engraved signature on the top? Were the scarcity and limited production run an intentional charade to create marketing hype? Or, was there true merit behind having a piece of equipment tuned by Ken Ishiwata’s ear? This was going to be my most expensive audio-related purchase to date. After much deliberation, I placed my order for the SA-KI Ruby in December of 2018. 

“Meeting” Mr. Ishiwata

Shortly after I placed my order, I inquired with Marantz’s American headquarters to confirm the exact production numbers for these limited-edition pieces. I got a vague and inconclusive answer, so I thought, “Why not go right to the source?”

I decided to contact Mr. Ishiwata by the not-so-clever method of blindly guessing his email address and sending my inquiry. Much to my surprise, I didn’t receive a bounce-back notification. Instead, a day later I received a response from Mr. Ishiwata himself! It impressed me that he took the time out of his day to respond to me. He didn’t ignore my email or pass me off to one of his associates. He casually replied as if we were old friends who spoke often. I didn’t realize it at the time, but this would be the start of a year-long email exchange, where I got to know Ken on a personal level.

He politely informed me of the European production numbers, as well as the estimated number of units that would be reaching North America. I replied, and we started chatting more about the newly released Ruby components. He shared some information and insight into his design and engineering goals and explained more about what was going on inside the Ruby gear on a component and integrated circuit level. He said that it was “his favorite player,” which is quite a compliment after 40 years of designing hi-fi equipment!

Getting My Own SA-KI Ruby

A few days later my very own SA-KI Ruby arrived. I hooked it up and began to fully explore its capabilities. It’s taken me nearly two years to be able to sit down and write something succinct and meaningful about its sound quality, and not because I wasn’t enjoying it. Rather, it’s because my system was growing, and I was learning what to listen for by attending audio shows and reviewing hi-fi equipment. As preamps, amps, speakers, and cables were swapped out and evaluated, one component that never left my system was the Ruby. Throughout all of the changes, its sound signature remained constant.

SA-KI Ruby Sound Signature

It’s not easy for me to describe the sound signature of the SA-KI Ruby. There are no euphoric overtones, boosted bass, hyper-detailed treble, or any of the other common ways that some equipment attempts to grab you. The Ruby simply does what I believe any competent DAC should do, present music without editorializing or coloration.

In this regard, the Ruby executes Mr. Ishiwata-san’s vision in stunning fashion. It’s neither warm, cold, bright, or dark. It is neither analog nor digital sounding. It simply makes music. It’s inherently difficult to pinpoint why a component sounds musical. In my experience, I believe it’s a result of the equipment getting out of the way and letting the music speak for itself.

Much like how a painter starts with a completely blank canvas, the SA-KI Ruby only gives you what you put into it. Whether listening to CDs, SACDs, or when using the digital coaxial input with the Lumin U1 Mini streaming transport for Tidal and Qobuz. Since all of these sources are up-sampled to DSD before playback, full justice was done to preserve the source material.  The music emerged from a silent background, demonstrating the Ruby’s low noise floor.

I easily heard this when playing SACDs, where the Ruby’s S/N ratio reaches a lofty 112db. Like the painter strategically letting certain areas of his blank canvas show through on the final composition, the strength of the SACD playback was in the blackness between the notes. The nuance when a coarsely plucked guitar string fades into darkness before you’re startled by the next note. The eerie sensation when the music reaches an explosive crescendo and then stops on a dime, leaving behind a several-second long reverb of the recording space. The complex layers of instruments, vocals, and rhythm were effortlessly discernible, allowing me to pick and choose favorite micro-details to follow along with. The SA-KA Ruby flawlessly demonstrates the massive dynamic range of a well-mastered SACD.

The sonics were also genuinely impressive with lossless FLAC files via the Lumin U1 Mini streaming Tidal and Qobuz. Demonstrating its transparency, the Ruby allowed the above-average performance of the Lumin to shine. It resulted in a spacious and exciting sound, with excellent holographic and three-dimensional imaging effects. Tidal’s quality is an experience to behold via the U1 Mini through the SA-KI Ruby. It will completely change your expectation of what Tidal can sound like if you’ve only ever heard it through your PC or a lesser streamer. When the sound is this good, and the library this vast, you might even forget about listening to vinyl.

Ken Ishiwata’s Departure from Marantz

On May 16, 2019, I read a press release announcing Ken Ishiwata’s departure from Marantz after 41 years with the company. In fact, I read it several times. I couldn’t believe that after so many years they had decided to part ways. Ken’s quote said, “It must be [a] big surprise that I’m not part of Marantz organization… I thought I’d be forever a part of Marantz. Unfortunately, that’s not the case.” This inspired me to email him again just like an old friend certainly would in this situation. I expressed my admiration for his impressive legacy with Marantz and provided words of support about his departure.

He replied later that day, and echoed the same feelings from the press release quote, saying, “I never thought such a day would come…..  As you know Marantz was Ken Ishiwata and Ken Ishiwata was Marantz…..” I could tell the split had hit him hard, like a punch to the gut. Ken was someone who lived to work, not worked to live. Marantz was his life and designing the company’s electronics was his passion. Clearly, no longer being a part of Marantz wasn’t sitting well with him.

One Last Email

I checked back in with Ken in August to see if he had accepted a position with a different company. He said other companies had approached him with offers but nothing had genuinely interested him. I encouraged him to turn to music during this difficult time. I believe music is the one thing in this world that will never let you down. In the last email he’d ever send to me, he said, “Music will always make me smile.” This is when I realized he was a music lover first and an audiophile second. This love is fully realized in his design, execution, and the resulting performance of the SA-KI Ruby.

SA-KI Ruby, a Fitting Swan Song

On December 3^rd, 2019, I read another press release. It was the somber announcement that Ken Ishiwata had died on November 25^th at age 72, reportedly of an autoimmune disease. This time, the news hit me like a gut-punch. I immediately thought back to our last email exchange in September and how I had never replied despite meaning to. Now, I would never be able to. This made the messages we did share even more meaningful. I’m grateful that I was able to offer Ken some solace during a difficult time in his life.

My short relationship with Mr. Ishiwata-san gave me a unique insight into his mind and his thought process regarding equipment design. It made me realize that sometimes an audio component is more than the sum of its parts. Befriending Ken created experiences that I will remember each time I listen to music through my SA-KI Ruby, my reference DAC.

May Ken’s spirit and love of music live on in his final design. The SA-KI Ruby is a fitting swan song for a 41-year career with Marantz.

Editor’s Note: Want to read more posts from Drew? Take a look here.