This website is intended for audio hobbyists and enthusiasts with an interest in practical electronics and DIY audio engineering.

It is a non-commercial project that presents a collection of custom-built designs, including DACs, amplifiers, power supplies, and mechanical enclosures. All projects are based on real implementations that have been built and tested.

The goal is to provide clear and practical reference designs that allow others to build high-quality audio devices. The content is aimed at those who prefer hands-on work with circuits, measurements, and physical hardware rather than purely theoretical discussions or ready-made commercial solutions.

The primary focus of the site is DAC design, supported by related areas such as amplification, low-noise power supplies, and custom enclosures. The designs follow a modular approach, allowing different parts of the system to be reused, replaced, or upgraded without redesigning the entire setup.

I try to keep articles as simple and readable as possible. However, this may sometimes mean that certain technical details are not fully disclosed. If you have questions, feel free to contact me via email, LinkedIn, or Instagram. I will try to respond as soon as possible. Your questions may also lead to updates in articles or the addition of a FAQ section.

The design approach is based on a sound-first principle while keeping solutions reasonably cost-effective. The focus is on simplicity, modularity, and electrical stability.

Particular attention is given to power supply design. In practice, well-designed low-noise and well-implemented supply stages have a significant impact on overall performance, often more than expected.

DAC naming is color-based and follows the PCB solder mask color.

Black DAC refers to designs based on AKM chips. White DAC is used exclusively for the CS4398 chip. Blue DAC covers the PCM179x family (PCM1794, PCM1796, etc.), but not PCM1793, as it has a completely different architecture.

Green DAC is used for experimental designs. That’s why some projects in this category may start from revision 1.2 instead of 1.1. At the moment, there is only one Green DAC project available, based on the PCM5122 chip.

Yellow DAC is used for older multibit chips, currently represented by TDA1387. Purple DAC refers to ESS-based designs, currently using the ES9028Q2M.

This color-based naming scheme is a simple but practical approach that makes it easy to quickly distinguish between projects and avoid confusion. Of course, you are free to use any PCB mask color you prefer.

DAC projects are divided into two main revisions. Revision 1.x designs can be powered directly from transformer AC, and also support DC input. Revision 2.x designs require external DC power, preferably well-regulated and low-noise. Please take a look at the provided photo, here you can see when DC supply is needed - there are "+" "-" and "GND" signs are been printed.

DAC boards are designed to be mechanically and electrically compatible within the same revision wherever possible. In practice, this means that PCBs within the same version can be replaced or upgraded without redesigning the entire system. For example, a Yellow DAC Rev2.1 (TDA1387) can be replaced by a Black DAC Rev2.1 (AK4493SEQ) without changing the power supply, OLED, or enclosure. The same applies to Rev1 designs - for instance, a White DAC Rev1.2 (CS4398) can be replaced by a Blue DAC Rev1.2 (PCM1794 or PCM1798).

Physical aspects such as mounting dimensions, OLED interface, and USB placement are kept consistent across revisions. This allows different DAC boards within revisions 1 and 2 to fit into the same enclosure without mechanical changes. This approach makes it easy to experiment, upgrade, and adapt systems without rebuilding everything from scratch

White DAC 1.2 and Blue DAC 1.2 are designed for direct connection to a USB–I2S interface. In most other projects, there is an option to install a galvanic isolator between the USB interface and the DAC. Using galvanic isolation helps to break ground loops and reduce noise coming from the USB source (such as a PC). In practice, this can improve overall signal stability and reduce unwanted interference affecting the DAC section. The isolator is optional, but recommended when aiming for the best possible noise performance, especially in more sensitive setups.

All DAC designs support OLED displays based on SH1106 or SSD1306 controllers. To use the display, MCU control is required. Communication is done over I2C, and the +3.3V supply for the OLED is provided directly from the board. The display is used to show sample rate, active digital filters, and the selected input source. The interface remains consistent across different projects.

All DAC designs are based on a set of core principles that keep them consistent across different versions.

PCB: I use two-layer PCBs with SMD components on both sides. This approach is fine for hand soldering in a home lab, but naturally more challenging for industrial production. From a signal integrity point of view, it helps to keep traces very short and allows placing the MCU on the opposite side of the PCB from the DAC chip, which helps reduce EMI coupling.

Control: STM32 microcontrollers are used due to their good performance and reasonable cost. DAC Rev1 designs are based on STM32 F030F / F070F / G030K / F103C series, while DAC Rev2 designs use STM32F030C series MCUs. The MCU communicates with the DAC chip via I2C bus. Some designs can also operate in standalone (STA) mode, but this comes with limitations - f.e. OLED control and output relay functions are not available.

USB Interface: All DACs allow direct mounting of a USB interface on the board. Different USB-to-I2S solutions can be used, including Amanero, XMOS, and CT7601-based interfaces. For my designs, I personally recommend the Amanero Combo384

Output buffer: I use Class-A output buffer for all DAC projects, based on npn transistor such as BC547 and j-fet load transistor f.e. SK170 or SK117. Because the buffer output voltage is approximately −0.6 V DC offset, a coupling capacitor is required. This buffer can be omitted in many designs if a direct op-amp output stage is preferred.

Operational amplifiers (OPAs): I personally prefer TI OPA16xx series in SOIC-8 packages, f.e. TI OPA1612, but the choice of op-amp is flexible. For DIP-8 implementations, good options include LM4562, LME49720, NE5532, AD827, and many others.

All projects on this website are made manually and are based on real, physically implemented and tested hardware. No AI tools are used to create schematics, PCB layouts, or system designs.

This is not a virtual or simulation-only environment. Every design - including schematics, PCB layouts, power systems, and enclosures - is developed for actual construction and use. The focus is on real components, measurable behavior, and practical assembly.