In Barn for Review: totaldac d1-unity DAC

You’d be forgiven for thinking this is another photo of the totaldac d1-tube DAC/Streamer that’s been living in the Barn since 2020. But it’s not.

What we have here is the new, and reportedly improved, d1-unity DAC from France’s totaldac. The d1-unity is one of three new totaldacs that share the new “unity” DAC architecture.

twins! the d1-unity atop the d1-tube

totaldac explains:

The “unity” architecture allows a better clock distribution, a lower jitter, a lower R2R power supply rail impedance and a lower noise in the digital section.

The output stage is also fully new, in term of components and in term of schematics, and using discrete components exclusively.

This new output stage produced a 3.5V unbalanced signal and a 7V balanced signal with low impedance for the best versatility, to be connected to all preamps, all integrated amps and also directly to all power amps.

Brient reports, “The ‘unity’ architecture gives more presence, more contrast between the timbre of each instrument, more contrast between the size of each instrument, more clarity at the same time as more body and more dynamic, the sound is more realistic and natural giving you more pleasure and no fatigue.”

The d1-unity shares the same basic architecture as every other totaldac in that it is a non-oversampling discrete ladder DAC. The d1-unity employs 1 R2R DAC per side (100 Vishay Foil Resistors) and offers the typical totaldac ins and outs. The power supply is outboard and not pictured, and the included plastic remote offers basic operational functions including volume, input selection, and access to a number of features like PHASE, EARTH (when “CONNECTED” is selected the signal ground is connected to the earth. When “UNCONNECTED” is selected the signal ground and the earth are isolated), DISPLAY (on/off), and TREBLE FIR (When “ON” is selected the non-oversampling treble loss is compensated to get a flat frequency response. When “OFF” is selected the DAC is a pure NOS (non-oversampling) DAC with some treble attenuation).

I wrote about my first totaldac back in 2012 (!) so I look forward to spending time with the new d1-unity for our 10th anniversary.


totaldac d1-unity DAC
Price: 12500euros incl VAT in Europe, 11500euros excl VAT out of Europe (appx $12,500USD)
Company Website: totaldac

Specifications

-192KHz asynchronous Xmos USB, 192KHz coax RCA, 192KHz AES-EBU, 96KHz optical, selected from a remote control.
-44.1KHz, 48KHz, 88.2KHz, 96KHz, 176.4KHz and 192KHz, 16 to 24 bit formats supported.
-as an option, DSD (DoP standard) supported on coax, AES-EBU and USB inputs.
-embedded custom clock with anti-jitter FIFO memory.
-3.5Vrms max RCA, 7Vrms max XLR analog output.
-volume control, adjusted by a remote control and an OLED display, works for all inputs.
-phase polarity selected by remote control.
-non-oversampling DAC compensation filter activated or disactivated by remote control.
-display switched off by remote control.
-R2R DAC technology using 100 pieces of 0.01% VAR Bulk Metal® Foil resistors Vishay Foil Resistors.
-class A discrete transistor output stage.
-external power supply to minimize the noise on the embedded preamp.
-aluminium and PMMA enclosure with massive pure copper antivibration plate.
-power consumption 14.2W @44.1KHz, 16.5W @192KHz.
-DAC dimensions: height 110mm, width 360mm, depth 290mm.
-power supply dimensions: height 65mm, width 122mm, depth 180mm.
-weight: 7kg.