By PSW Staff • February 2, 2011 Bruce Jackson PA EVOLUTION I sold out of JANDS and planned on traveling, meeting Roy Clair around 1970 when he came to Australia with the band Blood Sweat and Tears. He brought the sound system with him because there was nothing in Australia. The PA was the first we had seen of a horn system in Australia. Before his arrival, he had the “W” bass boxes built to save shipping weight, and its affiliated costs. Roy put four 15-inch woofers in the two W boxes, added his multi-cell mid-range horns and “bullet” superhigh tweeters to make a three-way system. The show was outdoors, and I was very impressed; although in retrospect, the Altec (Lansing) 1567 tube mixers, Altec cut-only EQ and domestic crossover by Pioneer were pretty basic by today’s standards. The crossover gave you a choice of six, 12 and 18 dB/octave crossovers and the hiss came for free. Linkwitz-Riley crossovers were unheard of. Roy invited me to come and visit Clair Bros in the U.S., so I stopped by on my way to London. Clair Bros was really small, based in an old barn north of Lititz, Pennsylvania. Morris Kessler, founder of SAE, a pioneering hi-fi company, had built what was effectively his high-end consumer graphic EQ into a card designed for a mixing console. Clair Bros had installed these printed circuit cards into a few mixing consoles, and this was my first opportunity to use selective EQ circuitry. Early EQ using magnetics. Inductors made from transformers, pictured along the bottom, work with capacitors to create frequency selective boost or cut. (click to enlarge) It used old-fashioned toroidal inductors, made from wire that was wound around magnetic cores that varied from the size of a nickel up to the size of a mini doughnut. When you combined these different sized inductors with various capacitors, it created a switchable, frequency selective circuit that allows for boosting or cutting a particular band of frequencies. These inductor based circuits are expensive to manufacture, and as soon as op amps started to improve, they were replaced by electronic equivalents. That’s the interesting part. I didn’t really think the electronic equivalents sounded as nice as the original. There was something about the simplicity of the original inductor style EQ circuitry that sounded warm and natural, which complimented the music flowing through them. We later found that this was largely due to the limitations in the new integrated circuit amplifiers in the non-inductor versions. I ended up working with Clair Bros for a number of years. It was a fun time because most of the stuff we take for granted today was being developed out of necessity. Elvis Presley was my main mixing and sound engineering job. We had to develop methods to hang sound systems – not for sound quality – but to sell the maximum number of unobstructed seats. We were first to use the upside mounted chain hoists to lift the PA, copying the idea from one of the touring ice shows. Read the rest of this post 1 2 3 4 5 Comments Have something to say about this PSW content? Leave a comment! Cancel reply Scroll past the ”Post Comment” button below to view any existing comments. Your email address will not be published. Required fields are marked *Comment Name * Email * Website This site uses Akismet to reduce spam. Learn how your comment data is processed. Peter Maurer says I spent many hours in that Santa Monica garage with Bruce showing me all what he describes in the above story; and then so many more amazing projects he developed. Bruce, we will miss you and never forget you; R.I.P. Anisa says I love you uncle Bruce. I will miss you so much!!!! I still can’t believe I was just talking to you 2weeks ago. You always talked about how I’m growing up so fast and asked me about school. You were the only man that I could call the wizard of electronics.It came as a total shock to me when I found out. I’ll be praying for you and of course my aunt and cousins. I feel so awful. Thanks for taking me ice skating for the first time you know how much I wanted to go. I appreciate everything you ever did for me. I can’t stop thinking about you and I love you. Sooooooo much <3 ); anisa/ aj David Gibbons says I had the pleasure of knowing Bruce for about the past 10 years. In my experience, he was everything people have said about him-warm, funny, egoless, brilliant, gentlemanly-and if you worked in pro audio, inspirational. I always felt privileged to know him, but he was so easy-going, you just felt glad to be with him. He and I talked about digital console design from time to time while I was working through the design cycle for the Digidesign VENUE consoles. He was working on the Lake Contour at the same time, and I could tell he was itching to do another mixing console design. It’s really too bad for the world of live mixing that he didn’t get a chance to do so. His legacy will guide us into the future; a better one for his having been here. Farewell Bruce. Tagged with: Apogee Bruce Jackson Concerts Heritage and History Lake · all topics Subscribe to Live Sound International Subscribe to Live Sound International magazine. Stay up-to-date, get the latest pro audio news, products and resources each month with Live Sound. Subscribe Today!