I was so impressed with Rethm Audio’s Maarga loudspeakers, which I reviewed last year, that I spoke to Mark Sossa, of Rethm’s US distributor, Well Pleased Audio Vida, to arrange to buy a pair of Rethm’s magnum opus, the Saadhana. My timing was serendipitous -- Jacob George, the sound architect at Rethm, told me he’d made some improvements in the Saadhana, and that I’d be sent the first pair of units to incorporate them. The changes included a complete redesign of the bass chamber and driver configuration, improved woofers, and new isolation footers -- George promised substantial improvements in the already excellent bass reproduction.

The Saadhanas fulfilled that promise -- as much as I love the Maargas, I’m glad I’ve upgraded. The differences I hear between the two models are the Saadhanas’ ability to fill my fairly large living room with a soundstage even wider and deeper, and with much more substantial bass. The Saadhana’s subterranean bass -- it extends down to 22Hz, compared to the Maarga’s 28Hz -- is well defined, meaty, and tightly aligns with the outputs of the wideband drivers.

But I needed two new power cords -- the Rethm speakers aren’t shipped with power cords for plugging their powered bass modules into the wall. Up till now I’d been reluctant to fall down the rabbit hole of high-end power cords, fearing the damage it would do to my wallet, and had justified this reluctance by assuming that only abstention would keep the cost-benefit ratio in my favor.

Essential Sound Products

Nonetheless, I wrote to Michael Griffin, of Essential Sound Products, and asked if he could send me two of his MusicCord Pro cords and a pair of his Reference Duplex outlets -- I wondered if I’d hear any difference between them and my standard power cords and outlets. He agreed.

An upgrade from stock?

At $249.99 USD each, the MusicCord Pro isn’t expensive by audiophile standards, and I was interested to hear what it could do for the Rethms, as compared to generic power cords. After six months of using his cords and outlets, I’ve become a believer in the importance of Griffin’s products -- they provide a lot of sound quality for the price. I asked him some more questions about his ideas, and about what makes his cords and outlets special.

I’d met Griffin at AXPONA 2018, where his cords were part of one of the most impressive-sounding rooms at that show: Randy Forman’s Finest Fidelity room, which featured Ken Stevens’s Convergent Audio Technology amplification and A.J. van den Hul’s Crimson Stradivarius phono cartridge (my reference), among other products. When I asked Griffin how he’d become a purveyor of clean power, he told me that it had begun with a love of music. Influenced by his father and uncle, he learned early in life to appreciate high-performance audio gear, and owned his first component stereo system before he was in high school. He considers himself to be, first and foremost, a music lover, and focuses on designing power products that provide sublime emotional satisfaction to the listener. He grew up listening mostly to R&B and jazz, but felt that some of the music of his youth had not been very well recorded. This influenced his desire to make a better power cord that musicians and recording engineers, as well as music lovers, could appreciate and afford.

In 1991, Griffin bought his first audio component with a detachable power cord: a preamp. That stock cord was thin -- 18 gauge -- and he noticed that his power amp had a much beefier, 14-gauge, hardwired cord. Curious, Griffin bought a 14-gauge detachable cord and tried it with his preamp. While the 14-gauge cord made a big difference in the sound, not everything he heard was an improvement. He could hear more bass, but it wasn’t as well controlled as before; the stereo imaging was less precise; and the high frequencies were rolled off. Regardless, he was surprised that there were any audible changes at all, let alone changes this big -- as no audio signal is passed through the power cord, he wondered how it could affect the sound so much. Griffin reviewed some of his college textbooks to help make sense of this, but at the time, he was simply trying to improve the sound quality of his own audio system.

The other thing that spurred Griffin’s interest in designing power cords was the difference in sound he heard between LPs and early CDs. As many of us remember, when CDs were introduced, in the early 1980s, they were touted as a superior recording medium to vinyl. Griffin told me that he believed this claim, and bought a then-state-of-the-art ReVox CD player, and CD editions of a few recordings he already owned on LP. Comparing LP and CD editions of the same recordings, it became apparent to him that, at that time, LPs sounded better than CDs, particularly in terms of midrange purity. Griffin surmised that while AC power distortions can be introduced by any component in the signal chain that has a typical power supply, record players aren’t burdened with the complexity and associated potential distortion caused by a power supply that interfaces with the signal-processing circuitry. In LP playback, the cartridge creates the electrical signal by taking the physical motions of the stylus caused by its tracing of the record groove and converting, or transducing, those motions into electrical impulses varied by changes in the magnetic field created by the cartridge’s magnets and coils. In his experiments, Griffin came to find that, once he was able to significantly reduce or eliminate AC-induced distortions, digital playback could approach the level of refinement of LP playback, particularly in terms of midrange purity.

Another observation that Griffin believes is significant to audiophiles is the relation of digital bit depth and sample rate to a recording’s overall fidelity. He feels that while analog-to-digital and digital-to-analog converters have improved significantly over the years, the development of more sophisticated power cords, and the improvements in the sound quality of digital front ends that they make possible, have borne out just how important it is to eliminate as much AC-induced distortions as possible. Moreover, Griffin’s experience in working with recording and mastering engineers has told him that when AC-induced distortions are eliminated or significantly reduced, the differences in sound quality in recordings made at different bit rates become relatively subtle and much harder to hear.

Most of us who live in North America get our electricity from AC mains connected to a national power grid. But whether that power is generated by water, coal, nuclear, or solar means, what’s most important in determining the sound quality of an audio system is the wiring between the voltage step-down transformer outside the building and the audio component’s power supply. At the step-down transformer, the means of energy transmission changes from high-voltage coaxial cable, where it’s carried via a magnetic field, to 120V AC mains, where current is conducted via copper or aluminum wiring of various gauges into the building’s installed wiring to its wall outlets, and finally through the power cords to each audio component.

Electrical codes in North America specify that AC mains wiring must be a minimum of 14 gauge for 15-amp service, and 12 gauge for 20A service. The stock power cords sent with most audio components are 18 gauge, which insert a relative bottleneck in the circuit. That’s a key reason why you can hear such significant differences by changing the gauge of your power cord. Some of the distortions we hear are actually caused by stock power cords.

Griffin recommends isolating your audio system from sources of electromagnetic interference, such as the motors of refrigerators and air conditioners, by putting it on a dedicated circuit. He also suggests trying to eliminate sources of radio-frequency interference (RFI) such as fluorescent lighting ballasts -- that is, “a device used to provide the starting voltage or to stabilize the current in a circuit (as of a fluorescent lamp)” -- and older dimmer switches. Because not all sources of RFI or electromagnetic interference (EMI) can be eliminated, Griffin’s third recommendation is to use shielded cables.

Because high-end audio is all about re-creating all the emotional content captured in the original performance, clean power must be the foundation on which a high-end audio system is built. It’s a relative miracle: electrons generated by a power system miles away flow through an electrical circuit into a home, then through an audio system to create a mechanical soundwave that then impinges on a biological listening apparatus to produce chemical signals in our brain that register pleasure. Clean power at the start of the signal chain defines the system’s “performance envelope”; dynamic contrast, frequency range, tonal and spatial qualities, and resolution can directly affect the amount of dopamine our brain secretes.

Griffin feels that dirty power can compromise practically every aspect of an audio system’s sound. For example, grain, particularly in digital sources, and white noise, can cause a loss of resolution -- i.e., a system’s ability to reproduce the nuances and subtle details that better create the illusion of being in the acoustic space in which the music was recorded. Severe noise issues abound -- buzzes, hum, even faint radio signals -- that can distract the listener. More insidious are phase distortions induced by the AC power system, which can cause midrange thinness, harsh transients, and attenuated extension into the lowest frequencies, or the opposite: bass that’s bloated and poorly controlled. Griffin believes that much of the sound-quality problems thought to be part of the audio signal itself are actually created by dirty AC.

The MusicCord Pro

In 2005, Griffin decided to focus his efforts on designing a power cord that could become a reference for the audio industry. Such a cord had to offer genuine improvement in sound that could be supported by measurements, work well with almost all audio components, exceed industry safety standards, and, most important, be affordable for most music lovers, not just wealthy audiophiles.

Essential Sound Products

To meet these goals, Griffin reengineered the Essence Reference-II and came up with the MusicCord Pro. This was more difficult than he’d imagined, and took him three years. The result, however, combines a patented cable geometry with handcraftsmanship and mass-production processes.

In his MusicCord Pro power cord, ESP’s Michael Griffin has combined a number of thoughtful design elements to maximize its speed, phase performance, and current capacity. The cord is comprised of eight conductors of 20-gauge copper -- four neutral, four line -- connected in parallel and wrapped around a single, oversize core ground conductor of 12-gauge copper. These conductors are extensively shielded by four individual layers: inner and outer jackets are separated by a shield of braided copper to lower the noise floor; the entire cord is then enclosed in a protective sheath of woven polyester.

The plugs show a similar attention to detail, with solid-brass terminals and hand-soldered terminations. The entire assembly is certified hospital grade, meaning that it meets high performance standards of grounding reliability, assembly integrity, strength, and durability. Considering the price, the level of craftsmanship is impressive.

In Griffin’s mind, the MusicCord Pro proves that if a design is fundamentally sound, it can result in a high-quality, high-performance power cord made in the US for a reasonable price. He takes great satisfaction in noting that MusicCord Pro cords are equally at home connected to instrument amplifiers, recording-studio equipment, and high-end audio gear. Recording engineers have told Griffin that his power cords have greatly diminished their listening fatigue during long recording sessions. In addition, many audiophiles have said that his power cords make “digital” sound more “analog,” which Griffin understands as meaning that the midrange sounds smoother, more refined, more pleasing to the ear.

To refine his products, Griffin especially likes to hear from musicians who play acoustic instruments, because they’re intimately familiar with the sounds of those instruments. Griffin has received endorsements from a number of high-profile musicians who tell him that the sound of their acoustic instruments, when amplified using ESP power cords, is faithful to the instruments’ unamplified sound. Similarly, recording engineers value tonal accuracy over coloration, and their choice of Griffin’s cords has validated his design and guided his product refinement. I don’t know much about acoustic instruments, but I did plug my Tom Anderson electric guitar into my Carr Bloke amp, and was blown away by the increased purity and density of tone, as well as the layers of harmonics the MusicCord Pro revealed.

One thing that impressed me about Griffin’s work is his extensive use of measurements in designing his products. On his website he’s posted graphs showing the reductions in total harmonic distortion (THD) and intermodulation distortion (IMD) produced by a guitar amp after swapping out its stock 18-gauge power cord for a MusicCord Pro.

Essential Sound Products

Griffin believes that what’s most needed to advance power-cord design are objective measurements of their electrical performance, based on modern power-supply performance. His experience has been that, in contrast to audiophiles, record producers and engineers have generally been suspicious of the claims made for high-priced aftermarket audio cables, primarily because of the lack of measurements to help define performance requirements. In general, advances in circuit design and component specifications have promoted much faster rates of charge and discharge of stored energy. As these advances have occurred, designers of audio components have not formally defined, for example, what minimum instantaneous rate of current flow is required to ensure that the power cord is not a limiting factor in a power supply’s performance.


Griffin’s measurements support what I heard in my system. Comparing the standard power cords I had on hand with ESP’s MusicCord Pro, one of each plugged into my Rethm speakers’ bass modules, it was easy to run an A/B test by panning left and right. I was astonished and delighted to easily hear differences between the two cords, and how much the Saadhanas’ already amazing powered bass modules benefited from cleaner power.

The kick drum in Meshell Ndegeocello’s cover of TLC’s “Waterfalls,” from her Ventriloquism (16-bit/44.1kHz FLAC, Naïve/Tidal), had more powerful and resolute low-end wallop. The same was true of the bass in “Hard Place,” from H.E.R.’s EP I Used to Know Her: Part 2 (16/44.1 FLAC, RCA/Tidal), which sounded more authoritative and resounding.

Essential Sound Products

I then went on a tour of great bassists, bass lines, and bass guitars. Chris Squire’s Rickenbacker tone in “Roundabout,” from Yes’s Fragile (16/44.1 FLAC, Atlantic/Tidal), was more explosive, while John Entwistle’s Gibson Thunderbird in “I Am the Sea,” from the Who’s Quadrophenia (16/44.1 FLAC, MCA/Tidal), was even more relentlessly propulsive. Both bassists coupled highly melodic, contrapuntal bass lines with deep, rumbling, organ-like low-end notes to create an orchestral bass sound that the Saadhana-ESP combo seemed to delight in demonstrating.

Flourishes, Tales and Symphonies: Music for Brass and Organ, by the Chicago Gargoyle Brass and Organ Ensemble with organist Jared Stellmacher (16/44.1 FLAC, MSR Classics/Tidal), sounded richer, more sonorous, and better-defined with the ESPs in the system. I also appreciated the bone-quivering intensity of Stellmacher’s pipe organ in Craig Garner’s arrangement of the Adagio of Saint-Saëns’s Symphony No.3.

Essential Sound Products

Esperanza Spalding’s electric bass in “Earth to Heaven,” from her Emily’s D+Evolution (16/44.1 FLAC, Concord/Tidal), was titanic in scale. The soundstage was bigger with the ESP cords installed. The title track of Spalding’s Junjo (16/44.1 FLAC, Ayva Musica/Tidal) also showcased the Saadhanas’ strengths as enhanced by the ESP cords: The bass line was fatter but not amorphous, with defined leading edges and beautiful harmonics.


Essential Sound Products’ MusicCord Pro might very well have become the most cost-effective part of my stereo. Given its relative affordability in a sea of expensive competitors, my enthusiastic recommendation of it is a no-brainer.

. . . Tom Mathew

Associated Equipment

  • Speakers -- Horning Eufrodite Ellipse, Jamo R 909, Rethm Saadhana, Vivid Audio K1
  • Amplifiers -- Shindo Laboratory Cortese and Haut-Brion
  • Integrated amplifiers -- Luxman L-590AX, Spec RSA-F33EX
  • Preamplifiers --Linear Tube Audio MicroZOTL, Shindo Laboratory Monbrison
  • Digital sources -- Luxman DA-06 DAC, Schiit Audio Yggdrasil DAC, Innuos Zenith Mk.II and Zenmini music servers, Aurender X100L music server
  • Analog sources -- Garrard 301 and 401 turntables in Chris Harban custom plinths
  • Cartridges -- Hana SL, Miyajima Laboratory Shilabe and Zero mono, van den Hul Crimson Stradivarius
  • Phono preamplifiers -- Bob’s Devices Sky 30, Luxman EQ-500
  • Speaker cables -- Auditorium 23, High Fidelity Cables CT-1 Enhanced, Skogrand Ravel
  • Interconnects -- Bob’s Vintage phono, MG Planus 3, Skogrand Ravel, Swiss Cables Reference Plus
  • Power conditioners -- Shindo Laboratory Mr. T, Silver Circle Audio Tchaik 6
  • Accessories -- Acoustic Revive RR-888 low-frequency pulse generator, Kanso audio furniture, Symposium Acoustics speaker stands

Essential Sound Products MusicCord Pro Power Cord
Price: $249.99 USD.
Warranty: Lifetime.

Essential Sound Products, Inc.
PO Box 81998
Rochester, MI 48308
Phone: (248) 375-2655
Fax: (248) 375-2701

Website: www.essentialsound.com