SR: I see you have plenty of measurement equipment in the rack behind you. How do you balance measurements and voicing by ear during the development and completion stage of a new product?

LC: Indeed, I have a thorough set of measurement gear ranging from old still top-performing machines to some of the most advanced available which I keep calibrated and in use every day. Measurements are a necessary tool to support and validate a design. It is what you measure and how you interpret it which makes all the difference. Certain standard measurements have relatively modest relevance in the context of a music signal which shows dramatic dynamic swings and varies over time in a hugely complex manner. Over the decades I developed my own suite of measurements and interpretation criteria but circuit development still involves a continuous repetition of cycles: prototyping, measurements, listening, modifications, measurements, listening, modifications, measurement, listening… When a project has reached a more advanced stage, I carry out tests with systems of very different components and loads to verify the behaviour of my equipment in divergent contexts.

SR: During the listening tests do you have a pre-defined track list? Do you have a reference system against which you conduct A/B tests?

LC: I don't have a pre-defined track list. I prefer to use as many different music genres as possible. As for a reference system, indeed I built a few in my career but my reference is always live music. Always. I don't like to use A/B tests between gear except for super-fine tuning. My approach is more similar to the comparison-by-contrast method. Hence I listen to the same piece of equipment across multiple genres, recording techniques and venues to see how differently they render. The more difference I hear, the less coloured and synthetic my circuit will behave. This is for the rough stage. For later fine tuning, I can use A/B comparisons between two capacitors in the same junction or between two different operating points of a gain stage.

SR: Is there a section or component of your electronics that has the most impact on the overall sound?

LC: Every part is important but even more important is the balance between parts. But if I had to choose, I believe that the first gain stage of a circuit sets its signature. For that reason I believe that a full-fledged preamplifier is a must for any audio system that aspires to ultimate excellence.

SR: In this era of variable DACs, there are many proponents of going direct, claiming that this has not only a financial benefit but also delivers better sound due to a shorter signal path.

LC: I am perfectly aware of this narrative and respectfully yet firmly disagree. In all of my career, I have never experienced a situation where a well-executed properly implemented preamplifier was outclassed by a DAC. My experience across forty years is exactly the opposite in fact. To me it mainly comes down to subtle yet essential nuances that make the sound more natural and organic.

SR: When using a preamplifier, do you recommend matching it with a power amplifier by the same brand?

LC: A great preamplifier should improve the sound of any power amp. That said, the advantage of combining a pre and power amp from the same brand is that, if the musical intent behind them was coherent, using them together makes its realization stronger.

SR: Are there inspirational figures that influenced you during your career?

LC: Of course. There are many. I must say that most of the people I consider my masters have made their contributions to the audio playback sciences many decades ago. When I was young, I was an avid reader of electronics and acoustic publications from the classical age (1920s to '60s), digging into magazines and books which at the time one could only find in specialized libraries or at the university. Where transistors are concerned, most of the development related to their applications occurred between the 1960s and '80s. This is not to say there has been no progress since, just that at that time the fundamentals and main pillars of audio electronics were already defined. I could mention many names. I will limit myself to two or three I am particularly fond of. The first is H.F. Olson, a giant in the field of acoustics who headed RCA's research labs for many years. Acoustical Engineering (first edition published in 1940) is still considered a reference. The second is N.H. Crowhurst, a designer, journalist and popularizer who dealt with countless topics including audio transformers always with a sharp and unconventional vision. Last but not least, Jean Hiraga.