Fifth Element IZVOR
/Fifth Force

Digital playback has never sounded so full bodied,

tonally rich, naturally flowing, and ‘real’.

In 2014, our design engineer Darko Greguras began exploring the possibility of dispensing with the conventional Digital To Analogue converter chip. Instead, his aim was to create a discrete R2R Ladder DAC, using only the finest quality analog circuit components.

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Following twelve years of meticulous research and development, we give you the IZVOR DAC, a groundbreaking, breathtaking revelation.

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The IZVOR distinguishes itself as the first-ever DAC to use large, hand-soldered resistors rather than the usual surface-mount components typically found in ladder DACs.

Darko was able to fine-tune the IZVOR’s voicing by testing and selecting components from our vast selection of custom options, even going so far as designing an entirely new resistor for the project.

Below is a description of the development process from Darko: -

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“The word ‘Izvor’ can have many meanings but one stood out and best reflected the intention behind this project. For me, ‘Izvor’ represented going back to the fundamentals of digital-to-analogue conversion: exploring the engineering essence while staying in harmony with the materials and metallurgy.

This project has been driven for years by a passion to return to the basics, using selected, well-known and refined components to create a harmonious, discrete multibit digital-to-analogue converter.

Why? Because when you apply a carefully balanced group of parts, every step forward yields a fuller, smoother, and richer performance. In much the same way musical instruments are built, the key lies in harmonious and complementary properties.

Sound wise, the goal was to achieve greater contrast and grip, improved authenticity and timing, but at the same time a very composed and lush presentation.

This project did not come without its challenges. The resistors I wanted to use have a tolerance of 1%, which (if used in a conventional way, as other manufacturers do) is insufficient even for 14-bit performance in a discrete segmented DAC. So we had to think creatively and look for innovative solutions.

The technical design target was to stay within the AD1865 DAC chip specification, but to improve on it both objectively and subjectively, especially at very low signal levels. This Discrete DAC was modelled and designed around a segmented structure; 3 bits in the MSB and 16bits in the R2R sections. Particular attention was given to performance below −60 dBFS, where ambience, decays, and subtle details live. Izvor’s settling time was never in question due to a specific choice of the analogue switches and very careful decoupling.

To achieve this, we developed fast I²S real-time compensation and used measurement equipment with reliable 1-ppm accuracy. Corrected values were stored individually on each DAC board, each being effectively unique. This kept my friend and colleague Andrejs very busy!

There is no oversampling and no digital or analogue filtering, only a circular I²S buffer.

We tested everything at DC-level precision using an 8.5-digit laboratory instrument. The final result exceeds the AD1865’s measured dynamic range by more than 4 dB and, subjectively, the way the DAC loads the room feels far closer to an analogue source.

None of this would have been possible without a proper shunt power supply to support such demanding requirements and it was designed, specifically for the DAC, by Andy Grove. It is a solid-state interpretation of our patented Galahad feed-forward power supply, making it possibly to reach −130 dB noise floor.

Was the effort worth it? Absolutely!”