Rockin' and rollin'

It is tempting to yell out “yabadabadoo” once you’ve set your eyes on these speakers carefully handcrafted by the men and women of RTV Labs headed by Rolly T. Vicencio. Fred Flintstone will surely be rockin’ and rollin’ as these speakers shake out hard-to-resist, cardiac-arresting dance tunes. The speakers are literally housed in stones.

The idea isn’t new. What makes these speaker gadgets stand out is that they have been designed for home use. Exceptionally inflexible, concrete easily has a much higher “Q” than hardwood, marine ply and MDF (medium density fiber); the most common materials used in speaker enclosures. A higher “Q” means zero resonance especially in the lower bandwidth. Kick drums, stand-up/electic bass and pipe organs, among others, are reproduced without any sound coloration that is usually caused by vibrating wood panels. RTV’s concrete speakers’ bass response is incredibly good; not loud, but reasonably tight. My guess is that they can go down well below 35 hertz.

RTV’s use of vintage drivers – JBLs, Altec-Lansing – is another plus factor. Highly sensitive, these drivers with alnico (aluminum, nickel and cobalt) magnets are extremely easy to drive. A nine-watt amplifier (and higher) is all it takes to make these speakers sing. Equally sensitive vintage horn speakers are used for midrange and high frequency reproduction. With a combined sensitivity rating of more than 100dB, these drivers really rock! But it doesn’t stop there. The woofers, the mids and the tweeters are wired in a tri-amp configuration. This means that each driver is being powered by separate amplifiers with an electronic crossover dividing the sound frequencies. With this configuration, this system will certainly give you awesome dynamics.

I first saw similar stoned speakers in Malabon where a town sound festival has become an annual event. Humongous speakers were deployed in an open basketball court, each one trying to outdo the other in a sound competition. The enormous challenge is to have near-perfect sound quality despite a hostile acoustic environment.

Rolly, RTV’s top honcho, who hails from Malabon, says that the tradition started in the early ’60s when an audio dealer, in a marketing coup, paraded six of his customers’ stereo sets to an open basketball court for an audio exhibition. The gimmick was copied by other dealers in Metro Manila, but it was in Malabon where the novelty was totally embraced and has since become a yearly event eagerly awaited not only by Malabon audiophiles but its townsfolk as well.

Concrete was the material of choice for most speaker enclosures participating in the competition. The thought of these speakers performing so well in an open environment gave Rolly the idea that they would even sound better in-house.

Rolly finished his electronics engineering course at the Mapua Institute of Technology in 1971. Even as a freshman, he had already designed and assembled a slew of electronic gadgets such as passive crossover network, vacuum tube preamps and amps. After a brief stint as a teacher at Don Bosco College, Rolly worked for AKAI-Mariwasa where he was trained by Japanese audio engineers. He rose from the ranks to become the company’s production manager.

“My job at AKAI-Mariwasa contributed much to my desire to explore the audio world. It was really my great passion to develop a unique sound system that will satisfy my taste for good music. At first it was just a hobby but when friends and audio enthusiasts enjoyed what I created, it became a business as orders started coming in,” says Rolly.

With business partner Jerry de la Rosa, RTV Labs currently designs and manufactures state-of-the-art audio system that can link up an eight-way driver system via a multi channel electronic cross-over, and single-ended and push-pull tube amplifiers. According to Rolly, through his company’s tireless research and development initiatives, RTV was able to make more improvements so that concrete speakers can be adapted for home audio.

* * *

For comments or questions, please e-mail me at audioglow@yahoo.com or at vphl@hotmail.com. You can also visit www.wiredstate.com or http://bikini-bottom.proboards80.com/index.cgi for quick answers to your audio concerns.