Whilst talking to Alexey, I pointed at the amplifiers' output tube. One pays it foremost attention of course. That's like how, during a concert, one first notices the soloist and only afterwards begins to get interested in the background musicians - the viola, French horn, drums. The vector of our perception always moves from the surface inward even though we may limit ourselves to superficial interest for lack of ability or will to dig deeper; or because appearance seems more interesting than essence. With Bravo it is different. The fact that Syomin would turn to the Soviet 6с19п triode was quite predictable after the earlier launch of the Inspiration and Lilt Studio Reference One amps already based on it. In my opinion those were very successful components. I remember cautiously sharing with Alexey my high regard for this tube's high musicality. I felt cautious because one cannot ascribe the final sound to the qualities of a single component, even an excellent one just as a soloist can't be a success without the support of an orchestra and conductor.


"I have sufficient knowledge of all existing electron tubes and their technical and sound faculties. My preferences are the result of long years of experience. Gradually I whittled things down to a range of components with suitable features and the best of 'voices'. But one tube really stands out. It sits above any competitors on technology, reliability and, even more importantly, for its musical handwriting. This is the 6с19п, one of my all-time favourites. I've been using it for more than 20 years in various machines. I based a universal preamp on it. I applied it as an output tube. Some of my amps with this triode have been in operation for more than a quarter century already. This tube works miracles. By the sum of its advantages, I think even the 300B lags behind it. My 6ж43п driver is very musical as well and undoubtedly outbid Western competitors with which I compared it. It drives the 6с19п via a bifilar interstage transformer.


"In the Bravo preamp, I use four 43 which I previously exploited in the output stages of my DACs and phono preamp. Thanks to the mono amp schematic, it was possible to shorten the signal path by half over the Inspiration. Bravo also has lower distortion and better transformers. Bravo's tube schematic is the same as the Lilt Studio Reference One but the levels of implementation differ like heaven and earth. The output transformers alone are good enough to be patented." Still, it could seem that Alexey almost forgot about the 6с19п if we skip the recent Inspiration and Lilt Studio Reference One. That's because the last 5-6 years had seen him court other favourites – first and foremost the 300B, then the 6F6 and the 6L6 in the latest Blackbirds. "Of course I didn't forget about the 6с19п. I just like to experiment. That includes tubes. I don't limit myself to using the same solutions over and over again. I try various ways to obtain a unique but diversified sound. Each Bravo monoblock parallels eight 6с19п in a single class A stage. Max power is 30 watts, nominal power is about 20. To build up power in a single-stage class A amplifier by increasing the number of tubes isn't that wise. I had an idea to design a push-pull amp using the 19 by using four or five per phase for about 50 watts. A single-stage class A amp based on the ГУ-80 could output up to 100 watts but the ГУ-80 is not easily tamed. The Erato illustrates this perfectly. There are several problems to solve: how much power do you want, the VA and aspects like drive.


"If you use the popular 300B, you'll see that it is far easier driven than the 6c19п. When there is 200V on its anode, the cathode bias is 96V — approximately the same amount as for a 300В with 450V on its anode. But as a rule, the key factor for me is what sound can be created by means of a certain part." 6с19п specimens for the Bravo amps were thoroughly selected from large batches produced in the USSR during the 1970s. These are superior tubes with stamps of military acceptance. "The 6с19п is a stabilizer tube, therefore highly reliable. It was produced by Svetlana and other military plants. To adopt it to audio requires careful selection because the characteristics of these tubes vary significantly. For a stabilizer, tight matching is not very important but for audio purposes, the situation is quite different. Bearing in mind the high voltages this tube is rated to work with (240V on the anode), it has to be selected manually. I'm soon going to perform this task using a specialized test bench."


As I already said, good or even superior parts per se don't guarantee superior results. Magic wands and crystals exist only in legends and fairy tales. The notion that the success of any machine is inextricably tied to its parts list is similar to Leonardo Di Caprio winning an Oscar thanks to a bear that didn't survive. The bear ought to have gotten that statue – posthumously as it were. Like Stephen King once wrote, "don't piss on my leg and tell me it's raining". But here we're really discussing the Bravo monos whose success owes a lot to the output transformer and intricacies in the power supply. Alexey always pays the utmost attention to these aspects. Moreover, the output transformer for a chosen tube is the very first interface he begins any new project with. He only moves forward once the valve/iron pairing completely satisfies him. He won't hesitate to scrap a project if he doesn't find the results impeccable. That's exactly how the impressive KT-150 Blue Sapphire integrated started life.


On a whole, Alexei often constructs his signal path from input to output. That's how he tuned the sound of the transistor White Knight amp based on thermo-stable current modules (one of the more impressive items in this catalogue). The cores for the Bravo EI-core transformers are produced in Germany. "We have Russian transformer iron that is second to none (I used it for the Blackbird) but in this instance I needed plates with a wide window to build a large transformer having a high 670W rating. Therefore the creation of an output transformer for the Bravo monos could be called a project within a project. I developed a very complex winding system and the result is a really hi-tech part. Moreover, it was exactly what I needed." Alexey wound the transformer specifically for 4Ω taking into account common impedance variations in nominal 8Ω speakers. "I could have installed a switch between 4Ω and 8Ω but that would have sacrificed a no-compromise transformer. With a 4Ω load, the 8Ω windings would 'hang in the air', i.e. not work. The transformer then would behave 'underwound'."