In Slavic mythology, Zorya is the goddess of dawn. She is the one who opens the gates to the sun every morning, bringing light after darkness. I chose this name because it perfectly describes what a good microphone should do: not invent anything, not color the sound unnecessarily, but reveal what already exists, bringing it to light.
Every recording is born from an unrepeatable moment. A voice, an instrument, a nuance, an emotion. The role of a microphone is not to transform that moment into something else, but to capture it as completely as possible.
Zorya was born exactly from this philosophy. As many people know, I have never liked copying. In the audio world there are entire markets built around replicas of historic equipment. In the field of valve microphones the situation is even more evident: there are now hundreds of Telefunken U47 clones.
The curious thing is that none of them truly sounds like an original U47. Some modify the circuit, some use valves completely different from the historic ones, some use cheap television pentodes such as the EF80, adapted as best as possible for audio use. And then there are the output transformers, often made according to criteria that have more to do with cost reduction than with sound quality.
The truth is that copying is the easiest road. It is the road of those who need a reference because they are unable to create something of their own. I wanted to build a microphone that was only itself. A microphone that no one could constantly compare with an original from the past. A microphone with its own sonic identity. An SB-LAB microphone.
To start from solid foundations I chose a K47 capsule, one of the most appreciated and musical capsules ever developed, mounted inside a 60 mm style body that offers plenty of space for a mechanical and electronic construction without compromise.
The choice of valve was less obvious. Instead of pentodes such as the EF80 and EF86, used in many commercial projects, I chose the 5670.
The 5670, also known through its equivalents 2C51 and 396A, is an American double triode developed for professional and military applications requiring extremely high reliability. Introduced in 1952, it was used in VHF equipment, avionics systems and devices designed to operate up to 80,000 feet of altitude. It is a valve built to be rugged, quiet, stable and with low microphonics. These characteristics make it ideal for a valve microphone.
In the Hi-Fi world the 5670 has been known for decades as an excellent valve for high-performance preamplifier stages. The better-known 6N1 is a reinterpretation of the 5670, but a far less refined one.
What convinced me was a personal memory. Many years ago Giovanni Mariani, founder of GRAAF and one of the Italian designers I have respected most in my professional life, told me that he had used the 5670 in very high-level microphone preamplifiers. For me, that was an important confirmation. If a valve is able to excel in a professional microphone stage, then it can become the heart of a great microphone. And that is exactly what it became in Zorya.
Once the electronics had been defined, there remained the component that more than any other influences the character of a valve microphone: the output transformer. Here too, I decided to follow a completely personal path. For the core I chose Supermalloy, a material known for its extremely high magnetic permeability and for its performance in very low signal level applications.
The available cores were UI type. The simplest solution would have been to use two separate bobbins, one for the primary and one for the secondary. It is a common choice in many valve transformers, but it is not a choice I share. When two windings communicate mainly through the magnetic core, the higher frequencies and microdetail inevitably suffer. Contrary to many audiophile legends, no ferromagnetic material is truly efficient at directly transferring high frequencies. The finest information passes mainly through the correct coupling between the windings. For this reason I designed and made dedicated single-slot bobbins, printed specifically for this project.
The transformer was developed with a carefully planned winding structure, keeping primary and secondary as close to each other as possible. The result is a completely proprietary transformer, characterized by about 300 Henry of primary inductance and an output impedance of about 200 ohm. This is a sufficiently low value to drive professional inputs of 600 ohm and above without problems, even through very long cables.
During development another aspect emerged that I consider fundamental. Many valve microphones, if not all of them, provide relatively low output levels. This forces the use of high gain in the following preamplifier. At that point the final result depends not only on the microphone, but also heavily on the preamplifier itself. In practice, you spend a lot to obtain a quality microphone and then entrust a large part of the sonic personality to another device.
With Zorya I chose a different approach. The microphone already provides a high output level. This improves the signal-to-noise ratio, makes the use of very long cables less critical and, above all, drastically reduces the need for subsequent preamplification.
In tests carried out with an Avalon valve preamplifier it was necessary to engage the -20dB attenuator, because Zorya’s output level is significantly higher than what is normally expected from a valve microphone. The result is that what you hear is much closer to the native sound of the microphone. To the reality captured by the microphone.
To complete the project I also developed all the support electronics from scratch. Both the internal PCB of the microphone and the dedicated power supply PCB were designed from zero. The filament supply uses an inductor-filtered regulator, while for the anode supply I chose a 6X4 rectifier followed by a classic CLC filter. A traditional, reliable solution, perfectly consistent with the philosophy of the project.
From the power supply panel it is possible to select two polar patterns:
- Cardioid
- Omnidirectional
A second adjustment is also available, called:
- Fat
- Slim
This function allows the microphone response to be quickly adapted to the sound source and to the type of voice being recorded.
Zorya’s performance did not remain confined to the laboratory. The microphone was used for several months at The Walrus Studio in Spilamberto, Modena, by Roberto Bettini, who was able to work with both the prototype and the final version. His experience was extremely positive.
I used the SB-Lab Zorya valve microphone in the studio in its prototype form for several months, and recently tested the final version.
In my opinion, the Zorya microphone is characterized by high sensitivity. It is able to capture all the nuances of both simple and complex sounds, and has a powerful output that allows excellent signal-to-noise ratios to be achieved, even when recording relatively weak sounds.
When recording, due to its high sensitivity even at very low frequencies, it is advisable to use a high-pass filter in the preamplification stage set around 40 Hz.
Using the filtering options provided, it can adapt to different types of sound sources. Among all possible applications, I recommend it for recording vocals, where it can excel with thin voices such as female voices, giving them good body and presence, and with all acoustic instruments, especially those with high registers.
The post-production treatment of the recorded tracks is straightforward and the expected results are achieved, especially on vocal tracks, without the need to use complex sound processing.
Roberto Bettini
The Walrus Studio
Spilamberto, Modena
Many words can be used to describe the sound of a microphone, but in the end the only truly reliable judge remains listening. For this reason I decided to make available some recordings made with Zorya in real contexts and without artifices intended to mask its character.
- The first recording is dedicated to an acoustic guitar. In this case the signal coming from the microphone was recorded without any treatment. No equalizer, no compressor, no plugin, no software processing. What you will hear is simply the sound produced by the guitar and captured by Zorya.
- The second recording is a sung vocal test. Here too, the goal was not to create a finished production, but to allow the microphone’s behavior to be heard on one of the most critical and important sources of all. The voice is often the definitive test bench for any studio microphone.
- The third example comes from a complete recording performed by a Vasco Rossi cover band. Here Zorya is used within a real musical production, allowing its behavior to be evaluated in the context of a complete mix and not only on an isolated source.
For those who wish to carry out a more accurate listening session using a Hi-Fi system or reference headphones, the original files are also available for download in lossless FLAC format. Inside the ZIP archive you will find the three complete recordings used on this page.
>>> Download Zorya Microphone Demo Files <<<
The invitation is simple: listen, compare and let your ear be the judge. In audio, technical specifications are important, but listening always has the last word. But there is an aspect I consider even more important. Zorya is not just a prototype or an exercise in style.
A complete album has already been recorded with this microphone at The Walrus Studio in Spilamberto, Modena, and was later also released on vinyl. It is therefore not a project that remained on paper or confined to the laboratory, but an instrument that has already faced real professional recording sessions, contributing to the creation of a record intended for the market. For those who wish to hear a real example taken from this work, one of the album tracks is available on YouTube: https://youtu.be/dclP4Dq6hoY
Other professional productions and several bands have subsequently used Zorya during their recording sessions, confirming its versatility and its ability to adapt to very different musical contexts.
Zorya under the lens of the instruments
Real recordings remain the best method for evaluating a microphone, but I believe it is also correct to show some instrumental data collected during the development of Zorya. The following graphs are not intended to replace listening, but they allow a better understanding of the design choices that led to the final sonic result.
The first graph shows the bandwidth of the entire audio stage, including valve and output transformer. This test makes it possible to verify the frequency extension and linearity of the circuit, highlighting how the proprietary transformer developed for Zorya is able to correctly transfer both the lowest frequencies and the finest information present in the mid-high range.
The second graph shows the harmonic distortion spectrum. More than the absolute value of distortion, which is particularly low for a valve microphone, it is interesting to observe the distribution of the residual harmonics, present at particularly low levels. The harmonic structure contributes significantly to the perceived timbre of the microphone and represents one of the elements that differentiates a valve design from a completely solid-state implementation.
The third graph shows the acoustic response of the microphone in Flat configuration, without the intervention of the filters and equalizations selectable from the power supply. This measurement makes it possible to observe the natural behavior of the capsule and electronics, providing an objective picture of Zorya’s original voice before any adaptation to different sound sources.
As always, I invite you to interpret these data as a tool for further insight and not as a point of arrival. A microphone is not heard with the eyes, and no graph can ever replace what happens when a voice or an instrument actually starts to sound in front of the capsule.
Zorya represents my idea of a valve microphone. Not a copy of a classic. Not a reinterpretation of someone else’s project. A microphone designed, built and developed entirely in SB-LAB, starting from a blank sheet and arriving at a product capable of finding its own voice. If you would like to listen to it, try it in your studio or receive information about purchasing it, you can contact me directly. I will be happy to tell you about Zorya and, above all, to let you hear it.
