Originally published in 2015
Paul McGowan:
No, this post isn’t about some lame track about ‘dat bass‘, but it is about ‘dat bass’.
Over dinner last night with Infinity founder Arnie Nudell and PS Audio’s Bill Leebens, the discussion turned to bass. Better put, the lack of it in today’s speakers, something I constantly harp about in these posts. For those of you that have followed Arnie’s past exploits in speaker design, you’ll remember he was first to introduce the idea of servo bass in the Servo-Statik 1a. J. Gordon Holt, then editor of Stereophile magazine, wrote in 1968 that the speaker was appallingly expensive (a whopping $3,000) but of the bass he wrote:
the low end was improved beyond all expectation, and the 100Hz crossover from the Nine allowed it to put out considerably higher listening levels without strain.
Which brings me to the point of this post. Why do so few speakers–even subwoofers–incorporate servo woofers? Yes, they are technically challenging to design, but their benefits of lower distortion (by a magnitude), near perfect response, improved transients (they can reproduce a square wave) are mostly unachievable by any other means. True that you can equalize a woofer for the same near-perfect response, but lower distortion and improved transient response? Not a chance without a servo.
It boggles one’s mind that with today’s crop of mega expensive speakers, focused on the most minute of details, purporting to be state of the art, that none contain servo bass systems. Worse, most don’t even go that low in frequency. It is like designing a high end car, paying attention to every last detail–save one–the turbocharger to make it go fast. “Oh, when we said it was state of the art, we didn’t mean all of it.”
I don’t get it.