I know that you've worn a few different hats in the music biz. Tell us about that and how your previous experience led you to Apogee and influenced your current work.
Well, obviously I always had a great fascination for music and electronics — permanently looking for improving audio quality, especially making sound reproduction more musical. What my live sound experience taught me is the "no bullshit" approach. Stuff has to work under any condition at any time. So, making an occasional compromise in favor of compatibility and reliability is in the end, a much better decision. My studio days in Holland at Wisseloord were the schooling days of working and dealing with digital audio, which was at its infant stage in those days. I learned through practical experience and studying the books what digital audio could and could not do. The reason why I was attracted to it was the impulse response, the transients. I could never get that from analog. I was always disappointed how the drums came back from analog tape. You know, you set up your console, you feel every beat, it really hits your ear — and then you hear it back from tape and it is all muffled. Unlike many other engineers (US engineers especially), I loved and preferred digital and took the artifacts (harsher sound, thinner bottom end) for granted. Bob Clearmountain [Tape Op #84 & #129] introduced me to Apogee when he was working in Holland and was I assisting him. His Apogee AD-500 broke down and I fixed it for him. So that was my first contact. I really liked the converter and its philosophy. It was all about being portable and sounding good for rock and pop music, unlike the DCS and Prism converters, which I was already familiar with. They were too "clean", too sterile to my taste. Talking to the people at Apogee for tech support and acquiring equipment for our new mastering studio established a relationship and I started to do some part time work for them, like AES shows. Next, I decided to move to Los Angeles to start working for Ocean Way. They hired me for my digital expertise and I could not have made a better choice. For the first time I could hear what real good analog equipment sounded like. The ATR-124 was a killer, analog tape multitrack that not only had great warmth and bottom end, it had the transients too. Talking to many engineers who had sworn by analog, I now had a much better idea of what they did not like about digital. This knowledge piqued my interest in converters, recognizing that they were the weakest link in the digital chain. During my Ocean Way days I still worked part time for Apogee, and my first project on the side was an attempt to improve the sound of the AD-8000 (make it more analog). That became the SE. When Alan Sides (Ocean Way's owner) decided to sell half of the studios on Sunset Boulevard, I took that as a sign for a change of career. After many requests from Apogee, I finally agreed to become a full time design engineer. I felt I was ready at that point. So to answer the question in a short way, live mixing taught me that things need to work. Wisseloord studios in Holland showed me the power of digital audio and my experience at Ocean Way revealed how good analog can sound. My mission is to combine these three.
That certainly is the magic that fans of Apogee have come to know and love. But what I wonder is, at the heart of your boxes is an integrated circuit made by one of a handful of companies. Any of your competitors can go out and use the same chip. So how do you add that Apogee touch? How did you address the things that Ocean Way engineers disliked about digital?
Have two chefs make tomato soup and you are guaranteed that the dishes will taste different. Part of the secret is the ingredients, of course, but way more important are the quantities and the way it is prepared. A bit too much salt, or a little too much heatand the soup is spoiled. Designing a converter is not much different. You pick a part as the major ingredient and then your experience and your creativity decides what will be around it. The sound of a converter is not only determined by the converter chip, the analog circuitry around it is just as important. What kind of analog filtering is used, what types of op amps are implemented, what the power supply is like, what are the clocks driving the chip like, the PCB layout — all these factors affect the sonics and (to a certain extent) the specs. Over time I have learned to know the sound and behavior of many active and passive parts. So, besides trying to design the proper circuitry for the application from a technical point of view, I am also making artistic decisions of what would be the best sounding solution for that specific design. If you open up our units, it is possible you'll find an array of different op amps in the same audio path. Yet in another design, I could stick to one type. There is no particular rule or method — it differs for every new design. I should add that this is also the result of the continuous redesigning I do for every new product. I am always trying to find new inroads, improvements. I tend to recycle very little from old designs and I think it shows. We are getting better and better and more cost effective at the same time. The major complaint of engineers who prefer analog over digital is that digital is lacking in the lower midrange (no energy) and the widened (flat) stereo image, with a virtual "hole" in the center. Harshness was a very famous, other complaint, of course. But that has been pretty much addressed by any quality converter company. The former complaints, however, (no energy, flat, etc.) are a different story. I feel Apogee is one of the few companies to address these issues very successfully. Our current line has that same analog feel as tape. A lot of the guys I talked to in my Ocean Way days now use my converters and love them — some even prefer them over tape. How cool is that?
Wow! That must be the ultimate compliment. One thing you didn't mention is dither. Apogee uses aproprietary dither algorithm calledUV22. What's the story behind that?
UV22 has been available for over ten years now. It has seen one major revision about five years ago, in which a few things have been optimized and improved. This version has been labeled UV22HR. The story behind it goes way back in time, before I worked for Apogee. The major brain behind it is Jerry Goodwin, a professor in mathematics in Berkeley. The concept was born to avoid the solid noise floor that normal (triangular) dithering or noise-shaped dithering adds to data. It basically smears or conceals the information at the bottom of the dynamic range. UV22 is a different approach — instead of the full bandwidth noise it uses a concentration, or clump, of noise around 22 kHz. The purpose is to modulate the lowest bits instead of filling them. It is sort of comparable to the principle of using bias on tape to eliminate the non-linear behavior of the magnetic coating. Kind of anecdotal is the story how UV22HR came alive. The whole art of this technique is to create a noise that is a 100% random within that narrow range — no repetition allowed, since that will create idle tones. In order to create this perfect, "controlled" randomness we had every personal computer in the office run sequences at night for about half a year. All the results were being collected at the end of the week and sent to Jerry to analyze.
Crazy! So what did Jerry do with all that data?
He had written some applications to analyze the data. Probability analysis was, of course, his major interest.
Besides dither, another important factor in converter performance is jitter. What kind of artifacts will you hear in your audio if you have bad clock jitter? How has Apogee tackled the issue?
