May 2020

We Ask 10 Questions For High-End Audio Manufacturers
Featuring Bill Dudleston, Founder & Chief Engineer Of Legacy Audio
Enjoy the Music.com's 25th Anniversary brings you a new special feature!

  During Enjoy the Music.com's very special 25th Anniversary we're asking various high-end audio manufacturers to answer the same ten questions. Their answers may surprise you! This month we're featuring Bill Dudleston of Legacy Audio. Bill Dudleston is President and founder of Legacy Audio, a high-performance audio and home theater equipment manufacturer located in Springfield, Illinois. A member of the Audio Engineering Society and the American Institute of Chemical Engineers, Dudleston was recently inducted into a regional Hall of Fame, taking his place among mid-western Nobel scientists and statesmen. He is listed in Who's Who of American Businessmen.

Bill Dudleston is a University of Illinois graduate and inventor/ patent holder of numerous circuit topologies and acoustic alignments, Dudleston has pioneered controlled directivity loudspeaker designs, wave-launch coherence in low frequency radiators, dynamic braking in active speaker design, selectable directivity multi-way microphone arrays, feedback eliminating stage monitors, and isolated wall-mounting methods for in-wall/on-wall speaker systems. His innovation in business practice, customer service and technology is noted in Tom Pettsinger's The New Pioneers. Dudleston has published numerous articles on acoustics and loudspeaker design. He also authored Reinforcement, Resonance, and Reverberation: Fundamentals in Sound Control.

Bill Dudleston has designed and provided Legacy speaker monitors for Arista, Sony, Universal Music Group and archival organizations such as the Stradivari Violin Society. Multi-Grammy award-winning producers Rick Rubin, Antonio "L.A." Reid, and renowned mastering engineer, Herb Powers, have utilized and publicly touted the Legacy designs as assisting in producing artists Sheryl Crowe, Johnny Cash, Tom Petty, The Red Hot Chili Peppers, Mariah Carey, and Usher. Re-mastering engineer Steve Hoffman has utilized the Legacy speakers on re-issues of Elvis Presley, Frank Sinatra and Nat King Cole.

Q. What is your first memory of falling in love with music?

A. When I first heard a live solo cello as a child, I was totally reeled in by the harmonics. I've recorded live audio for more than four decades, and it’s the process of capturing something and trying to realistically reproduce it that has continually held my fascination.

Q. How did you first get introduced to high-fidelity audio gear?

A. Right out of college I had a six foot high equipment rack stuffed with a vertical linear-tracking table with Marcof PPA-1 (seen above) and moving coil cartridge. I added a Revox 10" open reel with the pro version of the dBX 224 which doubled the dynamic range of the deck. For speakers I robbed the sweet sounding 2" domes from some A/D/S 910, matched them to a Philips ribbon, SEAS midranges and a new pair of 10" woofers. I built up a Hafler DH-500 amp so I could bi-amp with a Paragon tube preamp and my Ampzilla on the woofers. Pretty nice for 1981. I spent a year getting the crossover just right.

Q. What is your favorite piece of vintage hi-fi, and why?

A. A tuner designed by Richard Modaferri and my two open reel decks.

Q. When did you decide to start a high-end audio company?

A. I began building loudspeakers at the age of 13 and started recording live performances at the age of 16 on my Akai open reel. In my senior year, I presented a technical paper on a coaxial loudspeaker design with a low turbulence port and an ambiance system with bucket brigade reverb.

Loudspeakers fascinated me the most as they are obviously the weakest link in the playback chain. I studied mathematics and physics while earning a degree in Chemical Engineering at the University of Illinois in 1981. I then worked as a chemical plant engineer and also managed a digital calibrations lab. During that time, I would come home at night and work another six hours on audio projects. By 1983, I had founded Legacy Audio with my father-in-law, Jacob Albright, who was a seasoned craftsman.

Q. What, and when, was your company's first product?

A. The Legacy-1 was my first model, which later became the Classic. It was a full range four-way that removed a lot of limitations from the two ways and three ways that were available. I was influenced on it by what I heard from the Dahlquist DQ 10's and just wanted something more dynamic than that.

Q. What challenges did you face during those early years?

A. I always consider challenges tremendous learning opportunities. By studying the design of microphones and the works of pioneers such as Alan Blumlein and Harry Olson, I was able to gain perspectives on loudspeaker design that others were not utilizing.

Q. How have your products evolved over the years?

A. Every year, we try to increase the acceleration factor of our loudspeakers. We're building the fastest stuff out there. Driver materials have evolved immensely. In our midrange drivers, for example, we've gone from Kevlar to Rohacell to woven Silver/Graphite to titanium encrusted carbon filled pulp.

All of our top of the line models are active designs, and this is very quickly trickling into our smaller speakers, such as Calibre. Active designs offer many advantages, the first being more compact enclosures. When using digital filters, one can achieve far less intermodulation distortion and more efficiency with less power wasted. Passive crossovers can consume a quarter of your amplifier output. If one can add DSP to the equation, all the inductive and capacitive reactances no longer dominate the crossover. For example, try to design a passive crossover within an octave of a driver's resonance. Unless impedance compensation networks are applied (which suck enormous power), the network is not effective.

Legacy has been an industry leader in digital signal processing. I partnered with Bernt Bohmer from Sweden to develop the Wavelet processor / DAC / Preamp / Crossover that provides state of the art room correction. It analyzes your room and creates an algorithm to correct for its effects, allowing you to hear your music exactly as it was intended to be heard.

Bottom line, the Legacy difference is dynamic range, lower distortion, faster acceleration and wider bandwidth. We'll continue to offer more active designs with DSP.

Q. What is your company's most popular product(s)?

A. The Focus speaker hands down. The model has been around for nearly 30 years, and has seen many of the improvements described above. It has truly become a world standard in full range speakers. Recording and mastering professionals worldwide including L.A. Reid, Rick Rubin, Herb Powers, Jr., SONY / Epic, Mercy Sound, Sono Luminus and The Bridge studios, to name a few all rely on the Focus speaker.

The speaker that taught me the most is Whisper. It is the first truly full range directivity controlled design. It offers increased clarity, greater placement flexibility and a significantly broader sweet spot. While guys like Earl Geddes and Richard Modaferri understood these benefits immediately, the hi-fi world was slow to understand. It took 10 years to overcome 20 years of Bose touting diffusive designs. Now, room correction and directivity control are well accepted techniques with pros and audiophiles. Look at the plethora of woofer based dipoles out there now. They are still not employing differential alignments using DSP to delay the front array which is the name of the game.

The Aeris system with our Wavelet technology really put us on the map in recent years. It can do things speakers are more than twice the price can't.

Q. What is your next planned product offering and its' features?

A. I've actually just released our new i·V amplifier series. Today's 24-bit recordings afford 35dB more dynamic capability over 16-bit. At the same playback level, that's 17.5dB more upward dynamics with a noise floor 17.5dB lower. This demands a much more powerful, yet quieter amplifier to take full advantage and the Legacy i·V amplifiers deliver. Utilizing the latest ICEedge amplifier technology, I designed this series with exceptional power, very high current (i) and voltage (V) for stability into low impedances with a peak output current capability of 38A.

Q. What advancements do you speculate high-end audio will offer ten years from now?

A. Speaker efficiency needs to increase industry wide. Less than 2% of electrical energy is converted to acoustic energy. Electrical transmission will change with application of Graphene superconductors in the signal path. We are already developing efforts in this area. Internal amplification is also eminent with small enclosures.

Manufacturer
Legacy Audio
3023 East Sangamon Avenue
Springfield, IL 62702

Voice: (217) 544-3178
E-mail: info@legacyaudio.com
Website: www.LegacyAudio.com