...Madsen makes an interesting first of what is becoming an impossible task: finding fresh lines in the most overworked book in modern jazz...the performer's pianism is often elegant and he is given a beautiful piano sound.
— The Penguin Guide to Jazz Recordings (8th Edition)

The pianist, who sounds nothing like Monk, nonetheless really gets at the freedom that lies at the heart of the tunes, and the results are warmly satisfying and instantly enjoyable. Madsen, currently based both in Austria and New York, deserves to be better known, for his versatile imagination, accessible swing, and self-assured touch. A fine disc, warmly recommended.
— Stuart Kremsky, IAJRC Journal

Like Steve Lacy before him, pianist Peter Madsen immersed himself in the music; the liner notes to this astounding CD report Madsen had transcribed most of Monk’s compositions by 1980, when his career was just beginning. Avoiding most of the more familiar tunes, the pianist approaches nine Monk compositions with microscopic attention and thunderous physicality.
— Randal McIlroy, Coda

Top 10 of 2003 List.
— David R. Adler, Coda

Mr. Madsen has broadened not only the scope of reinterpretations of the music of Monk by solo piano, but also the sonic palette available on the piano.
— Dennis Diener, Jazz Director - WNHU-FM (West Haven, CT)

The pianist takes on Thelonious head-on, and the results are neither imitative nor ironic. Madsen brings his own avant-garde side to the familiar repertoire.
— Steve Greenlee, Boston Globe

Running solo, he changes speeds and redesigns Monk's landscapes to suit his own moods—interpreting the minimal theme of 'Oska T' in a surprisingly dark and brooding manner, for example, slowing the pace of the waltz 'Ugly Beauty' or going outside the changes and rhythmic mold of 'Four in One'...he inevitably fleshes out Monk's skeletal forms with nice details and convincing gestures.
— Art Lange, Tower Records' ePulse!

Tackling the music of Monk is a daunting task, doing it solo takes a brave heart, and reinterpreting or reinventing it, as Madsen does here, requires complete understanding of the original compositions, and of ones inner self. Madsen deals a fresh full house on this project that is worth all jazz lovers attention, especially the spherically challenged.
— Michael G. Nastos, WEMU-FM, Ypsilanti, MI

...Madsen goes beyond simply covering Monk’s tunes, he collaborates with them, adding a distinctive creative spirit truly inspired by Monk’s free-thinking rebelliousness.
— Sound Tracks, NewMusicBox

He approaches Monk's music from two different sides. In one he calls on the mainstream experience he gained playing with the like of tenor saxophonists Stanley Turrertine and Benny Golson; the other extends the experimental position he has shown with players like saxist Ted Levine and bassist Mario Pavone. On many of these tunes he goes beneath the Monkisms to expose the early Broadway show tunes and Harlem rent party influences that are part of the compositions' DNA. Some of this recasting at least shows off Madsen's individuality and the pianist can be praised for giving us a different view of Thelonious.
— Ken Waxman, Jazz Weekly

After fully absorbing the songbook of Thelonious Monk, pianist Peter Madsen's dream of performing several of these works for a solo workout comes to fruition on this captivating release. Throughout this outing, he captures an aura and reshapes many of these works into what may appear to be, a concise history of modern jazz piano...the artist's brainchild imparts an indelible impression.
— Glenn Astarita, All Music Guide

...the fact that Madsen performs solo makes it abundantly clear that he can command the listener's attention through mastery of the material and remarkable technical facility, even on tunes that listeners have heard numerous times...it's Madsen's intelligent approach to Monk tunes—like his galloping, ominous introduction to 'Criss Cross' or his rumbling, prestissimo breaking apart of 'Four in One'—that invariably surprises the listener. On Sphere Essence, Madsen doesn't try to improve on Monk, he uses historical comprehension of several elapsed decades to thoroughly understand the music and put his own personal stamp on it.
— Bill Donaldson, Cadence

Madsen spreads the canvas with rich textures, bringing the well-known compositions to life through his expansive resolution of their complexities. Monk's music has had more exposure since his death than I would imagine he ever dreamed possible; yet Madsen stamps the selections with a unique identity and brings freshness and vitality to the repertoire. Madsen has captured Monk, and in the process confirmed a concrete link to his own musical personality.
— Frank Rubolino, AllAboutJazz

...a brilliant example of how time-honored standards can be seen from a fresh and exciting new perspective. Madsen's interpretation of 'Evidence' is startling in its brilliance, execution, and daring. He gives the piano several dimensions, plucking the strings, striking the keys, pounding out rhythm on the casing, making the instrument a living entity. Sphere Essence is stellar on all levels, transcending geometry, a pluperfect tribute to a singular, timeless musician.
— Terrell Holmes, AllAboutJazz-New York

His explorations of extended techniques appear to flow from the sense of freedom Thelonious Monk's music has imbued him with since he began transcribing it as a student in the 70's. The truth of the matter is that Madsen can also create a much wider range of sound from inside the piano than most players. His expressive re-imagining of 'Evidence' is a sonic treat, filled with the crystalline shimmers, something akin to a slapped electric bass and an echo of tympani. While purists may prefer a more reverential attitude, there's no denying the power of Madsen's wide-open approach to finding new ways to interpret Monk.
— James Hale, DownBeat

Madsen, who divides his time between homes in New York and Austria, presents a solo master class in which his musical mentor, Monk, is merely a starting point—harmonically, rhythmically, even structurally. Like Monk, Sphere Essence is pure introspection. Madsen has captured the essence of his idol and stamped his own futuristic essence in his own sphere.
— Harvey Siders, JazzTimes

Pick of the Week
— Jazz Excursion (May 25th, 2003)

Recommended New Release
— AllAboutJazz-New York (July 2003)

Best New Releases of 2003 List
— AllAboutJazz-New York

Top 10 of 2003 List
— Randal McIlroy, Coda