Regarding the B&G RD-75 ribbon drivers, I agree with Han_N that they like power and actually need quite a lot of power to come alive.
While the Genesis 1.2, Prime, & Dragon and Gryphon Pendragon use an array of tweeter drivers to take the high frequency response the rest of the way, beyond 10 to 18 kHz depending of design, the Wisdom Audio Adrenaline Rush and Infinite Rush models use a modified version of the B&G driver to reproduce the entire upper octaves out to 30 Khz without the use of additional tweeters.
“The Wisdom Audio SMART Planar Line Source designed by Tom Bohlender uses more filament trace runs that are narrower than the conventional RD50 or RD75 from Bohlender Graebener. Most important is it's patent pending circuit design dedicating certain runs for ultra-high frequency use. This SMART driver produces uncanny smoothness, greater detail, less distortion, but most of all--greatly improved high frequency response well above the range of 30KHz. All of this is achieved while preserving line source phenomena and negating the use of highly inadequate controversial techniques (added tweeter, or multiple tweeters, etc.). This allows for a single driver to produce over 80% of the spectrum, completely eliminating driver mating problems of phase alignment, speed matching, crossover abnormalities at highly exacting frequencies, and increased distortion. Although the Wisdom Audio SMARTdesign planar line source drivers are significantly better performers. Manufacturing them was an intensive and exhausting process. All Wisdom Audio products use the SMART planar line source drivers and they are exclusive to Wisdom products.”
My experience with the B&G ribbon drivers on my Wisdom Audio Adrenaline Rush is that they not only require an extreme amount of power to come alive but benefit from the active equalization tilt-up. It is daring, to put 1200 watts per channel of amplification on the ribbon towers but once you have heard them open up there is no going back. My Lamm 1.1 monoblocks don’t even begin to wake them up, my Spectral 360 monoblocks sound great on the ribbon towers but trip their protective circuit protection just about when things get interesting, my 500 watt per channel Belles MB-500 gives them a little more to work with but what surprised me is that I was actually able to clip the 1,000 watt per channel Maker Audio Signature Reference 3A monoblocks during the loudest passages when the music demands that you turn it up and jam. I have finally removed all power limitations from the ribbon towers by powering them with a set of Cello Audio Duet 350 amplifiers in bridged mode, capable of 1,200 watts per channel. It was/is with trepidation that I first used that much power on the ribbons, as replacement “SMART” 75” version of the modified B&G RD-75 ribbon drivers are unoptanium, but once you hear them open up you don’t go back. I quickly referred back to my owners manual, where it states that the ribbon towers on the Wisdom Audio Adrenaline Rush are rated for a maximum of 1,250 watts. So I’m listening on the edge but enjoying the bliss.
By the way, all these four (4) column systems obviously also require extreme power to drive their woofer/subwoofer columns to their full potential. I use four rare Rowland Research WL-500 monoblocks, which Jeff originally designed for Roger West at West Labs to drive the largest Soundlabs electrostats. I now use two WL-500 monoblocks per subwoofer column, after my mighty Krell KRS-400 and NRG Control A-400 monoblocks ran out of steam, at total in excess of over 1,000 watts per side on the subwoofer columns for a total system power availability of close to 2,500 watts per side, 5,000 watts total power for the system, from dedicated 240volt and 120volt systems from the electrical main transformer.
As you can see, these systems require massive amounts of power and unless you use several sets of Tube Research Labs Platinum Golden Triode 800 monoblocks, VTL Wotans or Siegfrieds, or Audio Research 750’s, I don’t see how you get there with only tubes and without employing high power solid-state amplification.
The bottom line is that I concur that the big 75” ribbon drivers need real power to come alive and sing, as does the rest these big four column systems as a whole, if you want that airy top-end with sparkle and a prodigious bottom foundation.
I hope that my experience with these drivers, albeit in modified form and in a different implementation, helps.
While the Genesis 1.2, Prime, & Dragon and Gryphon Pendragon use an array of tweeter drivers to take the high frequency response the rest of the way, beyond 10 to 18 kHz depending of design, the Wisdom Audio Adrenaline Rush and Infinite Rush models use a modified version of the B&G driver to reproduce the entire upper octaves out to 30 Khz without the use of additional tweeters.
“The Wisdom Audio SMART Planar Line Source designed by Tom Bohlender uses more filament trace runs that are narrower than the conventional RD50 or RD75 from Bohlender Graebener. Most important is it's patent pending circuit design dedicating certain runs for ultra-high frequency use. This SMART driver produces uncanny smoothness, greater detail, less distortion, but most of all--greatly improved high frequency response well above the range of 30KHz. All of this is achieved while preserving line source phenomena and negating the use of highly inadequate controversial techniques (added tweeter, or multiple tweeters, etc.). This allows for a single driver to produce over 80% of the spectrum, completely eliminating driver mating problems of phase alignment, speed matching, crossover abnormalities at highly exacting frequencies, and increased distortion. Although the Wisdom Audio SMARTdesign planar line source drivers are significantly better performers. Manufacturing them was an intensive and exhausting process. All Wisdom Audio products use the SMART planar line source drivers and they are exclusive to Wisdom products.”
My experience with the B&G ribbon drivers on my Wisdom Audio Adrenaline Rush is that they not only require an extreme amount of power to come alive but benefit from the active equalization tilt-up. It is daring, to put 1200 watts per channel of amplification on the ribbon towers but once you have heard them open up there is no going back. My Lamm 1.1 monoblocks don’t even begin to wake them up, my Spectral 360 monoblocks sound great on the ribbon towers but trip their protective circuit protection just about when things get interesting, my 500 watt per channel Belles MB-500 gives them a little more to work with but what surprised me is that I was actually able to clip the 1,000 watt per channel Maker Audio Signature Reference 3A monoblocks during the loudest passages when the music demands that you turn it up and jam. I have finally removed all power limitations from the ribbon towers by powering them with a set of Cello Audio Duet 350 amplifiers in bridged mode, capable of 1,200 watts per channel. It was/is with trepidation that I first used that much power on the ribbons, as replacement “SMART” 75” version of the modified B&G RD-75 ribbon drivers are unoptanium, but once you hear them open up you don’t go back. I quickly referred back to my owners manual, where it states that the ribbon towers on the Wisdom Audio Adrenaline Rush are rated for a maximum of 1,250 watts. So I’m listening on the edge but enjoying the bliss.
By the way, all these four (4) column systems obviously also require extreme power to drive their woofer/subwoofer columns to their full potential. I use four rare Rowland Research WL-500 monoblocks, which Jeff originally designed for Roger West at West Labs to drive the largest Soundlabs electrostats. I now use two WL-500 monoblocks per subwoofer column, after my mighty Krell KRS-400 and NRG Control A-400 monoblocks ran out of steam, at total in excess of over 1,000 watts per side on the subwoofer columns for a total system power availability of close to 2,500 watts per side, 5,000 watts total power for the system, from dedicated 240volt and 120volt systems from the electrical main transformer.
As you can see, these systems require massive amounts of power and unless you use several sets of Tube Research Labs Platinum Golden Triode 800 monoblocks, VTL Wotans or Siegfrieds, or Audio Research 750’s, I don’t see how you get there with only tubes and without employing high power solid-state amplification.
The bottom line is that I concur that the big 75” ribbon drivers need real power to come alive and sing, as does the rest these big four column systems as a whole, if you want that airy top-end with sparkle and a prodigious bottom foundation.
I hope that my experience with these drivers, albeit in modified form and in a different implementation, helps.
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