Spica TC-60 loudspeaker Manufacturer's Comment
Editor: Thanks for the excellent review of our TC-60 speaker, my latest attempt to coax a quart of juice out of a pint jar. John Atkinson did an amazingly good job of delineating the many tradeoffs involved in this (and any other) design. It is such a relief to have been reviewed by someone who actually has a real understanding and appreciation of what goes on under the veneers.
It is also a joy to be working with Richard Schram, Ric Mancuso, and everyone else at Parasound Products. Working with people who are as capable and enthusiastic as they are makes this a marriage made in, well, Alaska...
Regarding the leading-edge peak in the step and impulse responses, I recall from our conversations that JA's measurements are corrected for microphone magnitude irregularities, but not for phase errors. The ½" B&K (DPA) mikes have significant phase error at high frequencies, lagging 40° at 10kHz and fully 80° at 20kHz. The first ¼ millisecond of JA's time-domain graphs would all look better-behaved if this error was corrected. In fact, he may be making things worse by correcting the magnitude only.
I wish the TC-60's lobing behavior above the listening axis were better; it is an unfortunate consequence of the Bessel-based crossover function. But, given that this is the only significant compromise, I believe I can live with it for now, and hope to improve upon it in future products.—John Bau, Design Engineer, Spica
Editor: When the Spica TC-50 debuted over a decade ago, the high-end press heralded the scientific foundation of its unique design as the major contributor to its astonishingly accurate reproduction. Many thousands of TC-50s are still in service, and you don't have to look very far to find a serious listener who had—or still has—them. It's also amazing that, years later, others have not been able to improve upon, much less fully comprehend, John Bau's landmark design for the TC-50.
John Atkinson's thorough and overwhelmingly favorable review of our new TC-60 is history repeating itself. His report gives a glimpse into the approach of this unorthodox but uniquely gifted designer. Read it carefully and you'll gain a valuable understanding of why the TC-60 sounds so musical and natural, and also of why it's such an important new product, bound to redefine value over the next decade.
For a little over a grand, including industrial-strength Gravity stands, Spica TC-60s give fresh meaning to the motto appearing on New Mexico license plates: "Land of Enchantment."—Richard Schram, President, Parasound Products