Kurt L – DK

“This isn’t a subtle improvement—it’s a clear and tangible leap forward. The
soundstage deepens, the imaging tightens, and everything becomes more
life like. The Regenerator has elevated my entire listening experience, making it
more immersive, natural, and fatigue-free. It’s now a permanent fixture in my
Hi-Fi setup.”

Smooth Generator
Earlier, I purchased the AUVA 50s for my speakers, AUVA EQs for everything
else, and the passive SmoothLAN from Stack Audio. All of these exceeded my
expectations—often in surprising ways—so I was naturally curious whether this
new active regenerator would also earn a permanent spot in my system.
I’ve been testing this compact unit for about a month now, and here are my
findings.

“Tea for Two” from Lyn Stanley’s Tribute to 1924 is a perfect showcase for
what the Regenerator brings to the table. The performance and recording—
already exceptional—become even more engaging. The soundstage opens up,
and the music blossoms like spring itself. The holographic presentation
becomes deeply immersive, pulling you into the performance. The entire album,
in fact, benefits from this upgrade. It’s a superbly recorded, produced, and
performed work—and the Regenerator enhances every facet with grace.

“Where I’ll Find You” by Joan Shelley demonstrates an expanded, more
enveloping soundstage. Her beautiful voice detaches effortlessly from the
loudspeakers and is rendered with remarkable clarity. Without the Regenerator,
her sibilants can verge on harsh, and the depth of the performance feels
slightly diminished. With it, everything snaps into focus. It’s as though a layer of
haze has been lifted.

“Blues Run the Game” by Headless Heroes also benefits significantly. Texture
becomes more defined, instrument separation improves, and subtle production
details—like the digitally added reverb—finally emerge with clarity. Previously,
those nuances were buried in the mix. This track also doubles as a great test
for comparing Ethernet cables: within seconds, you can tell if a cable is too
harsh (especially during the guitar intro) or if the reverb becomes unnatural and
fatiguing (around the 00:10 mark).

“Running Out” from Pretty Maids’ Syndicate album, recorded at Sweet Silence
Studios in Copenhagen, brings back vivid memories. I had the chance to visit
the studio during the album’s production and interview producer Flemming
Rasmussen. I was stunned by the sheer power of the drum sound—it was
massive. With the Stack Audio Regenerator, that explosive energy is preserved
but refined. The music is clearer, less fatiguing, and more listenable for long
sessions. Now, I can enjoy these heavy, highly compressed tracks for hours
without tiring my ears. That’s no small feat.

“Yesterday” from the 2023 remixes is as fresh as a summer breeze—it really
does sound like it was recorded just yesterday (pun intended). With the
SmoothLAN Regenerator in place, the delicate strumming of the guitar and the
nuance in Paul McCartney’s vocal become more vivid. The clarity and intimacy
are striking, breathing new life into this timeless classic.

“Say You Don’t Mind” with Hailey Tuck never fails to put a smile on my face.
The coherence of the instruments playing in harmony is delightful. On many
systems—even some high-end ones—this track can come off flat or uninspired.
Not so with the Regenerator. It transforms the track into an engaging, dynamic
performance that holds your attention from start to finish.

“Station VI: Sancta Veronica” by Liszt, performed by Leif Ove Andsnes and
The Norwegian Soloists’ Choir, conducted by Grete Pedersen, is another
standout. The emotional depth and spatial rendering are sublime. Every vocal
line and instrumental detail is presented with breathtaking realism.

“Beethoven’s Violin Concerto – Larghetto,” performed by Nicola Benedetti
(DECCA Records, 2025), also showcases the Regenerator’s finesse. There’s not
a trace of harshness, even as the piece reveals the tiniest sonic details.
Dynamics are nuanced and elegant, offering a nice balance of softness and
strength. The transparency and “hear-through” quality are simply spot-on.

“Girona” with the Kühn Quartet is a challenging track for many Hi-Fi systems.
There’s so much happening at once—but with the Stack Regenerator, it’s a joy
to follow each instrument. Every line is distinct, precisely placed, and
emotionally expressive.

These and other great tracks from my library are available on my Qobuz playlist,
right here:
https://open.qobuz.com/playlist/31512478

Power Supply Surprise
The included switch-mode power supply deserves special mention. It’s been
carefully tuned to match the Regenerator, and it’s honestly one of the best I’ve
tried. I compared it with a €205 Allo Shanti linear power supply. In blind A/B
tests (my wife kindly swapped the cables without telling me), I preferred the
Stack Audio PSU every single time. The Allo is excellent, no question—but the
Stack PSU just added that little bit more: a deeper soundstage, increased
resolution, and an overall sense of musical ease. Sometimes, bigger and more
expensive isn’t better—just different. In this case, Stack’s PSU is a perfect
match: simple, effective, and best of all, forgettable in the best possible way—it
simply works.

Sound of Science

With Stack Audio’s SmoothLAN Regenerator, digital audio takes a significant
step closer to the warmth and soul of analog, while retaining the precision and
clarity we love about digital. The slight edginess I sometimes noticed from
Qobuz (my preferred streaming platform for its excellent sound quality) is now
gone. Yet, the attack and decay of instruments like harps, guitars, and cellos
remain intact—only now they’re rendered with greater finesse and control.

So, should you upgrade your speakers, or invest in the Stack Audio
Regenerator? In many cases, the Regenerator will give your existing setup a far
more noticeable and satisfying boost. It reduces ear fatigue, increases clarity,
and improves detail retrieval. Vocals are purer, cymbals shimmer more naturally,
and decays linger beautifully. It doesn’t just make your system sound better—it
makes listening more enjoyable. And that’s what it’s all about.

This isn’t a subtle improvement—it’s a clear and tangible leap forward. The
soundstage deepens, the imaging tightens, and everything becomes more
lifelike. The Regenerator has elevated my entire listening experience, making it
more immersive, natural, and fatigue-free. It’s now a permanent fixture in my
Hi-Fi setup.

For many years, my system has been fully digital—except for the speakers. I use
a digital Lyngdorf streamer/amp, and I can say with confidence: for the first
time, my fully digital system now sounds analog again. And that’s one of the
highest compliments I can give. The SmoothLAN Regenerator restores warmth,
emotion, and musicality and reveals details previously hidden. It makes digital
feel human again.
© Kurt Lassen, 2025
International Independent Hi-Fi Reviewer, Sound Engineer, and Music Producer