Comprised of six equal-format panels arranged in a two-by-three grid, BA 2001 presents a quietly commanding investigation into the relationships between color, proportion, and perceptual sensation. Each panel shares the same fundamental compositional logic: a black rectangle resting atop a warm golden-yellow rectangle, the two forms together creating a compact unit that floats against a background moving through the amber, sienna, and deep russet tones of the red-brown spectrum. The backgrounds shift subtly from panel to panel, ranging from a luminous burnt orange in the upper left to a somber, earth-bound burgundy in the lower right, while the internal black and yellow rectangles vary in scale, from the diminutive pairing in the lower left to the expansive, nearly field-dominating forms in the bottom center. This systematic variation transforms what might initially appear as repetition into a rich meditative exercise in visual difference. Tirelli is deeply invested in the phenomenological tradition of color investigation, one that draws clear lineage from Josef Albers and his landmark Homage to the Square series, while asserting its own distinctly contemplative and almost archaeological sensibility. Where Albers approached color interaction with a quasi-scientific rigor, Tirelli inflects his panels with a warmth and material intimacy that feels more rooted in the Mediterranean landscape and the earthen pigments of antiquity. The mixed media on board lends each surface a subtle tactility, absorbing and diffusing light in ways that shift the apparent temperature of each hue depending on viewing conditions and proximity. The polyptych format is essential to this effect: no single panel is fully legible in isolation, and meaning accrues through comparison, through the eye moving restlessly between panels and registering gradations that would be invisible if only one were present. BA 2001 represents Tirelli at the height of his serial practice, producing work that is neither purely formalist nor purely expressive but occupies a thoughtful space between the two. For a collector, this polyptych offers the rare quality of sustained engagement, rewarding long acquaintance rather than yielding its full complexity on first encounter. The work functions equally well as a unified installation statement and as a record of an artist thinking rigorously through color across time, inviting the viewer into a slow and deeply satisfying form of looking.