JBL S106 Aquarius II

Name: JBL S106
Brand: JBL

You don’t find many of these—when you do, it’s like uncovering a prototype that slipped through from a parallel universe where JBL went all-in on exotic, hand-built audiophile art.

Overview

The JBL S106 Aquarius II isn’t just rare—it’s borderline mythical. This 3-way loudspeaker system was part of a fleeting moment in JBL’s history when the company ventured into the realm of ultra-low-volume, hand-assembled audiophile speakers under the Aquarius name. Very few were ever built, and those that exist are described as “Extraordinary and Nearly Extinct,” a phrase that captures both their sonic ambition and their near-total absence from the market. These weren’t mass-market floorstanders; they were closer to acoustic sculptures, conceived with a level of craftsmanship so intensive that it doomed them to obscurity before they ever hit a showroom.

What sets the S106 apart isn’t just its scarcity, but the philosophy behind it. Unlike the rugged, tour-ready speakers JBL was known for, the Aquarius II was built for precision. Every unit required hand-picked drivers—especially the midrange units, which had to be individually selected by JBL engineers to meet tight performance tolerances. The cabinets and hardware were handmade, a labor-intensive process that made production prohibitively expensive. This wasn’t a cost-effective product; it was an experiment in what JBL could build if commercial constraints were lifted. The result? A speaker that collectors describe as “Very Rare” and “Rarest of the Rare,” with a presence so faint in the historical record that even dedicated JBL archives barely acknowledge it.

Specifications

Manufacturer	JBL
Model	S106 Aquarius II
Type	3-Way Loudspeaker System
Drivers	One LE20 HF, two LE5 Mids, one 123 Woofer
Weight	about 80 lbs
Ship Weight	90 lbs
Impedance	8 ohms
Power handling	100 watts
Frequency response	70Hz - 20kHz
Sensitivity	90 dB

Key Features

Three-Way Driver Array with Precision Matching

The S106 Aquarius II employs a sophisticated three-way configuration: one LE20 high-frequency driver, two LE5 midrange units, and a single 123 woofer (a 12-inch driver). The use of dual midrange drivers is unusual for the era and suggests a deliberate focus on midband clarity and dispersion. More importantly, these LE5 units weren’t just installed off the line—they were hand-picked by JBL engineers to ensure consistent performance, a practice more common in studio monitors or high-end European designs than in American-made speakers of the time. This level of component curation hints at a system designed for critical listening, where tonal balance and phase coherence mattered more than efficiency or ease of production.

Handmade Cabinet with Acoustic Optimization

The cabinet is described as “Extremely Well designed,” likely due to its sealed enclosure design, which offers tighter bass control compared to ported systems. Constructed by hand, the enclosure avoids the cost-cutting shortcuts typical of mass production. While exact materials aren’t specified, the handmade nature of the cabinets and hardware points to a build quality far beyond JBL’s mainstream offerings. The result is a structure engineered to minimize resonance and internal reflections—critical for maintaining the integrity of a complex three-way crossover and multi-driver array.

Rear Deflection Panel with Diffraction Control

One of the most visually striking features is the rear-mounted “deflection panel,” which houses the two LE5 midrange drivers and the 123 woofer. This panel includes “wild looking diffraction cones and brackets,” suggesting an advanced approach to managing rear wave propagation and minimizing interference. By containing and shaping the rear output of the mid and low-frequency drivers, JBL may have been aiming to improve imaging stability and reduce cabinet coloration—techniques more commonly seen in research-grade or studio monitors than consumer loudspeakers. The high-frequency driver is the only one mounted on the front baffle, further emphasizing a design focused on controlled wave launch and time alignment.

Historical Context

The JBL S106 Aquarius II emerged as part of the Aquarius line, a short-lived series that included Models 1, 2, 2A, 3, and 4 around 1970. Unlike JBL’s commercial speaker lines, the Aquarius series appears to have been a boutique experiment—possibly conceived under the influence of James B. Lansing’s original design ethos—where performance trumped profitability. The S106, in particular, was not viable for mass production due to its reliance on hand-picked drivers and handmade cabinets, which drove costs too high for the consumer market. As one account puts it, production was limited “due to the way James designed them,” suggesting a design philosophy rooted in acoustic purity rather than scalability. These were not living room speakers; they were described as auditorium speakers, built for large spaces and critical listening environments, yet rare enough that even their existence feels apocryphal.

Collectibility & Value

Today, the S106 Aquarius II is among the most elusive JBL models in existence. Described as “Very Rare” and “Nearly Extinct,” it commands attention whenever it surfaces. A pair was listed for $475 in 2010, though the cabinets showed “dings, chips, and scratches.” More recent listings reflect a sharp increase in collector interest: €1,800 in 2019, $2,564 in 2024, and even a $4,999 listing on Reverb in 2024. These fluctuations suggest a market still finding its footing, where condition, provenance, and buyer awareness heavily influence price. Sellers consistently note “some cosmetic wear but are in good working condition,” but with no documented common failures or repair paths, maintenance is likely a bespoke challenge. Given the handmade nature and lack of service documentation, restoration would be a project for the deeply committed—not the casually curious.