Introducing the Rotaxis DAC – A New Era in Digital-to-Analog Conversion
After years of listening, testing, and rethinking what digital audio should be, I’m proud to introduce something that isn’t just another DAC—it’s a redefinition of what digital audio can sound like when built without compromise. This is the Rotaxis DAC.
It’s not just designed for measurements. It’s not another op-amp box wrapped in marketing.
Rotaxis is a ground-up, time-domain focused, passive resistor ladder DAC built for one purpose:
To render music in time, not in code.
What Makes It Different?
Most DACs today rely on high-speed digital correction tricks like delta-sigma modulation, noise shaping, or digital filters that manipulate the signal to achieve good measurements. Rotaxis does none of that.
Instead, it’s built around a unique architecture:
1. PulseAxis Ladder Design
At the core is a true resistor ladder array using 24 bits of resolution. Each bit is represented by a series of precision-matched resistors ( typically 64 for each exponentially weighted bit) arranged in a circular configuration we call the PulseAxis Array. These aren’t just resistors lined up on a board—they’re strategically interwoven in rotational rings to reduce electromagnetic interference, thermal drift, and crosstalk.
Each bit doesn’t fire statically. It fires with clock-controlled precision at 11.2mhz base rate with sub clocking nearing 100mhz— firing each ladder in timed quarter clock time quadrants grouped by current weighting (MSB’s first)—to allow each resistor to settle before the next one activates. This gives a completely clean handoff across voltage levels, with no overlap, no popping, and no zero-crossing errors. The averaging effect per bit outperforms the best laser trimmed monolithic designs and even approaches metrology levels, and is SCALABLE for everything from a future accessible entry level product with only 32 level unary rings per exponential bit, all the way to 4 rings of 64 in each singular bit!!! With physically interwoven rings on the PCB that rotate in opposite polarities to eliminate EMI RF. A self-cancelling noise system.
2. Thermaphase Averaging
Instead of applying digital noise shaping, the Rotaxis uses a proprietary analog system called Thermaphase, which is deterministic rotation per bit that ensures perfect thermal symmetry as well as injecting inaudible ultrasonic dither into the 8 LSB’s where real music lives. Rotaxis behaves the way true analog signals behave in the real world.
This allows for incredibly smooth low-level performance—something most DACs struggle with. In Rotaxis, the bottom bits—the bits where the soul of music lives—are given the most care: the best resistors, the most error-averaging, and the cleanest timing.
Idle tones are a thing of the past. The 64 bit rings prevent audible pattens, and send whatever is left well into the ultrasonics which is filtered by a 4 pole RC filter into oblivion.
3. GlitchLock Timing
Instead of relying on one massive clocked update cycle, Rotaxis staggers its activity with a timing system called GlitchLock, breaking the update cycle into quarter-clock pulses within the DAC, and eighth-clock offsets between the two polarity ladders. This ensures that current never surges or overlaps across bit boundaries, minimizing distortion and noise.
The result is ultra-low distortion—without any digital filtering or shaping.
4. Transformer-Coupled Class A Output
We don’t use op-amps. The Rotaxis output stage is fully Class A, discrete, and transformer-coupled using premium Lundahl components. This preserves phase, eliminates ground loops, and gives the kind of dynamic immediacy you’d expect from the best analog gear.
5. Modular and Upgradeable
The Core64 model launches with:
• USB, SPDIF, and I²S inputs
• Galvanically isolated power (external PSU only)
• No touchscreens, no noise—just a small LED volume and sample rate indicator
In the future, an external streaming and control box will connect via I²S over HDMI, letting Core64 owners expand their system without changing the DAC core.
Measured Performance?
THD+N better than –124 dB, real-world.
No noise shaping. No feedback. No tricks.
Just physics, design, and care.
