Union Supreme 6

Order-to-ship schedule [updated 4/23]

Satin Black - 5 week
Black Starlight - 6 weeks
White Starlight - 6 weeks
Cosmic Carbon - 6 weeks
Mercury - 7 weeks
Rustic Hickory - 6 weeks
Black Hickory - 6 weeks
Ruby Red Hickory - 6 weeks
Electric Blue Hickory - 6 weeks
Blue-Teal Hickory - 6 weeks
American Walnut - 6 weeks
Other finishes - 7 weeks+

Included: simple and effective press-fit protective driver cover, cleaning cloth, and oval-ended stainless steel set-screw footers (installed), plus 4x per speaker 1–1/2” [38mm] adjustable carpet spikes. Installed stud-style footers make effective adjustable footers for most flooring. Packaging is designed for easy unpacking/repacking and tough enough to survive rough freight handling and reuse.

Price is for a matched pair. Singles are simply half price—if you need a single please email us and we’ll send you quote with payment link. In addition to the cabinet finish you can also select black or silver aluminum tweeter lens and driver trim ring, selected at the end of the checkout process (no up-charge).

Union Six Supreme is a medium format floor-standing loudspeaker. U6 Supreme builds on the essential agile, bursty, toneful sound of Union Six, extending its range and articulation and further focusing its acoustic output for even less cabinet dissipation. Harmonic content extends out to 29kHz and bass digs a tad deeper than Union Six, but is noticeably harder-hitting. Locating all of the moving elements around a single axis makes for an exceedingly cohesive and unified wavefront but in this case, we use the full Soul Six integrated-flux driver with main driver and ring-radiating supertweeter fully conjoined. Union Six Supreme is astonishingly vivid, yet nuanced and subtle when it needs to be. It delivers salacious slam and scale in real-world spaces without forcing you to organize your room around the speakers. Discover intricacies you've missed in your music until Union Six Supreme, and you're likely to hear new energy in dynamic swells, too.

U6 Supreme features our new more sophisticated ZuGriewe and scatter plate internals that eliminate the fussy floor gap and instead allow the main driver to "see" the room via a rear exit. You can place Union as close as 2" [51cm] from the wall behind it. It is both highly efficient and generally amp-friendly, with its 8 ohms impedance.

Union reviews

“Union Six sound anything but entry-level and can, truly, be your last speaker purchase.… I wish more companies would build entry level products like Zu does. The Union 6 has my highest recommendation, and is easily the best passive speaker I have heard under $3000.” - Sam Rosen, Positive Feedback Review

Legendary Performer 2020 - Enjoy the Music // Best of 2013 Award - Enjoy the Music

Easier to understand, setup and use

Tapping R&D work done for Definition Six and Soul Six, Union Six Supreme also introduces new technology within the cabinet’s acoustic functionality, greatly improving the bass through midrange performance over what we have been able to implement at the more affordable end of our designs in the past. The Henthorne Disrupted Flow Filter consists of a wide-band "scatter plate" that combines with air mass load tuning and the ZuGriewe function to optimize the acoustic impedance adaptation of the driver to the room. Designed initially for Definition Six, its first market appearance is in Union Six. Floor gap tuning is banished as we are able to put the exit interface out the back of the loudspeaker. Cabinet resonance distortions are held to very low levels through efficient energy transfer (1st rule: try not to induce harmonic resonance in the first place). The "decoherence" function of the scatter plate and a wide bandwidth / low Q distribution of plate modes within the cabinet design further minimize spurious resonances. Implementation of the scatter plate complex dovetails with our 10” [26.2 cm] coaxial driver as if it was specifically engineered around it, because it was.

Union 6 Supreme specifications

Bandwidth: 30 - 29k Hz [in-room average]
Sensitivity: 99 dB-SPL @ 2.8V, 39” [1.0m] from FRD face to mic [2π - 4π transition @ 200 Hz]
Impedance: 8 ohm nominal full spectrum Z-weighted
Wavefront: virtual point source
Near Field Transition: 10” [25cm] (driver face to your nose on axis)
Max SPL Program: 120 dB-Z (slow)
Max Input Power: 150 W (300 W w/ high-pass at 50 Hz, 12 dB/octave)
Left/Right Pair Matching: 0.25% on drivers and 0.1% on all other components

Amplifier power output guidance

2 - 15 watts for low to moderate sound pressure levels
15 - 50 watts for moderate to very loud SPLs
50 - 150 watts for very loud to ear damagingly loud SPLs

Build specifications

Internal Cable: Zu Event Mk.II harness with silver plated connections
FRD: ZuCX-ND-8-N151M (10.3” coaxial paper/CNT cone, under-hung 2” [50.8 mm] coil on paper/Kapton former
Tweeter: Eminence N151M
High-Pass Network: single element mono pole filter (Jupiter Copper 1.0 µF)
Crossover: none, and no filter components on FRD
Cabinet: North American made composite wood, skinned with real wood veneer or epoxy
Bottom Insert Threads: 3/8–16 (9/16 hex nut—14 mm wrench can be used but is tight)
1–1/2” [38mm] adjustable carpet spikes

Factory burn-in

400 hours for Union Six Supreme
(200 hours for standard)
Factory burn-in runs 24/7 cycling every 12 hours—moderate levels by day and soak levels by night. Program is full-bandwidth hard hitting music. Final QC is always post burn-in process.

Dimensions

12 x 12 x 36 inches [30.5 x 30.5 x 91.5 cm]
12 x 12 inches [30.5 x 30.5 cm] footprint
FRD protrudes 5/8” [16mm] from the face of the cabinet
Binding posts protrude 1-1/8” [29mm] from the back of cabinet
Union Six Weight: 60 pounds [27 kg]
Packaged Weight: 70 pounds [32 kg]
Package Size: 17 x 18 x 41 inches [43 x 46 x 104 cm]

Input Connections

ZuB3 via speakON NL8 (parallel with binding posts)
Posts accepting 1/4” [6.3 mm] and oversized spades, bare wire ≤ #4 AWG [5.1 mm], banana plugs

Other Detail

Union 6 Supreme entered production May 2022
Union 6 supersedes Union Mk.I - in product 2012 - 2014

Warranty

Like everything we make, Union Six Supreme is built to last a lifetime—cabinet materials, adhesives, driver assemblies... every component is a quality part engineered and built to create a loudspeaker system that will continually satisfy and amaze decade after decade, backing up that claim is our liberal five year limited warranty to materials and workmanship. Warranty does not cover misuse, abuse, components upstream from the loudspeaker system, modifications or non-factory overseen service. Full details here.