It would have been easier to develop a solid-state device. Instead you took the rockier path.
Correct. Our acoustic microscope enlarges not only what the stylus reads from a groove plus hum but whatever appears in the input stage from a tonearm, cables, improperly shielded connections and so on which the first tube gain stage amplifies followed by the second and third stage. A tube itself is quite a noisy hum-inducing device although all that happens a few dozen decibels below the music signal. Yet with all the necessary gain stages the character of a tube gets a dozen times more noisy or capricious than a transistor. So all those technical issues really don't make tubes the best choice for a phono stage. Yet their tonality, musicality and naturalness remain attractive even for this application. So designers must weigh the pros and cons. It was a difficult decision and I believe many other brands concluded that it couldn't be done. As a result they developed hybrid circuits where the first gain stage uses transistors with the extra advantage of low impedance which is a good thing for cartridges; and very low noise which is beneficial for the signal. They only use tubes in the subsequent stages. At LampizatOr this would have gone against our core philosophy and diluted our credibility. To insist on pure tube gain thus was our biggest challenge. Getting rid of all hum and noise in the first gain stage took us almost 5 years and dozens of almost-ready prototypes. After trashing numerous PCB and prototypes and losing a lot of money, I just couldn't give up. I had to finish this project no matter how much longer it would take or how much more it would cost. The issue of hum and noise had to be solved and a high level of performance achieved from all the innate musicality of tubes.

Did your know-how of DAC development help at all?
Yes but perhaps 90% of the knowledge we accumulated over the years which proved most useful for this project was on how to overcome failure, how to chase alternate solutions, how to approach logistics and mechanics of prototyping. It wasn't about how DACs work. That knowledge was not applicable.

How about at least power supply design? Did anything from your prior digital work translate there?
The power supply is almost identical because that wasn't a real issue. At first we did try to develop an overkill PSU but quickly learned that it wasn't necessary, only significantly increased costs because it took up more space, ran hotter, increased the number of parts we had to use and would have just been for show. One of the things I'm really proud of is that we never do anything just for show. If we use something in any of our machines, it means it had to be used to achieve certain results. If there is something not really essential and just there for the wow effect, I remove it even realizing that customers who buy with their eyes may disagree. I don't care. We have a limited budget for R&D so we choose to use it where it really matters.

Yet it is also true that over the years you significantly improved cosmetics even inside the chassis. I remember the times when your circuits looked a bit chaotic and some potential customers were deterred. Having peeked inside the VP4 Silver and Pacific DAC, now you are using great-looking perfectly made PCB and everything feels really orderly.
Some may think otherwise but we do listen to our customers, reviewers and so on. In the past I was a man who knew very well how I wanted my devices to sound and didn't like others to tell me what they should look like. I learned though that people who buy hifi products want them not only to sound great but also please their eyes. I finally decided to stop fighting them. As a result we started doing things not only in the right way but to also offer something people can be proud of possessing and displaying. Our current products look really good also inside even where you can't see certain things after removing the hood. So a customer who decides to peek inside one day won't find anything I'd be ashamed of. Each of our models has to be well-made, look great and sound the way I consider good. Obviously I never work on a project alone. Usually the development team consists of four people. I'm the one who doesn't care much about the aesthetics but there is always someone on the team who tracks that and won't let me introduce a new product until it also looks great.

Let's stay with a feature your DACs and phono stages share: weight. Does the VP4 Silver really have to be as heavy as it is?
To do something right—and I'm not even talking about an uncompromising design, just a good one—it must be big. If I didn't have restrictions, I would make our DACs and phono stages even bigger. Only then would they be as I really want them to be. For example, I would love to have an oversized transformer with at least 50% excess power. Ours only has 20% extra. To use a bigger one, we'd have to deal with more weight. That requires a thicker bolt which could damage the plate it is screwed to so we'd need a thicker plate. A thicker plate is heavier and probably bigger so we'd need a bigger chassis. That gets heavier so its walls must be thicker to sustain proper rigidity. A bigger heavier device needs a bigger sturdier shipping carton. So just by using a bigger transformer for a few more watts of power, we arrive at a 20kg heavier shipment and a price increase of 40-50%. Each design decision has consequences. I always laugh when I read about an uncompromising design because I know it's untrue. There is always some compromise involved. Ours is rather reasonable but still results in half-meter depth and 20kg. There are many pocket-size phono preamplifiers to market and they also offer sound quality but I wouldn't know how to make one.