I have been a long time fan of Chord Electronics and the bulk of my orders are to Chord customers. I do provide a range of isolation solutions for all their DACs and, if you've been following me, my current Chord DAC in hand is the Mojo2. It became my favorite DAC with the addition of my signal & power RF isolation kit. Many users adopted my approach, but for some, the extreme measures were a distraction from just buying a DAC that performs at its best out of the box. If that sounds like you, then consider the Holo Cyan2 as my recommendation.
Released in 2023 for use with software upsampling, Cyan2 is a pure NOS R2R design with separate processing path for PCM and DSD. The challenge for PCM reconstruction using R2R is varying resistor precision...which is overcome by using a resistor array and error corrective measures. For DSD, the resistor array is not used: all that is involved is a low pass filter and a clean analog output stage ...and this really elevates the sound. Cyan2 supports both 44.1kHz and 48kHz DSD rates up to DSD1024. IMO the sweet spot is 48kHz DSD512 (PGGB denotes this as DSD512₄₈). Comparing Mojo2 at 24-bits/768Hz vs Cyan2 at DSD512₄₈, one is immediately struck by the improvement in Cyan2 tonality, more bass resolution and even less digital hash. Cyan2 is a perfect match for PGGB's superior DSD modulation and is now my daily listen.
Cyan2 has a superior (galvanically isolated) USB input - borrowed from the higher cost May/Spring DACs. I added USB•FILTER and my ferrite shielded USB•CABLE to get it to the level of Mojo2's optical isolation (BTW, I tried to add OPTO•USB but Cyan2's proprietary USB design was incompatible). Cyan2 also has a simplified front panel of LEDs similar to Mojo2 colored balls. This is a design choice to reduce RF noise by avoiding a digitally controlled display. I further isolated Cyan2 with filtered battery+inverter power (as also Mojo2) and applied several layers of DAC•WRAP.
Cyan2 only provides line-level output - no volume control - for input to a preamp or headphone amp. In my listening tests, i used the following:
- HiFiMAN HE1000se headphones
- PGGB/MAX 512x1
- PGGB EQ using Harmon2018 convolution (AutoEq)
- Benchmark HPA4 (THX SS)
- Accustic Arts Preamp II MK2 (Hybrid Tubes/SS)
- ALLNIC HPA-10000 (OTL/OCL Tubes)
The Benchmark and ALLNIC were uber transparent yet almost 'too' revealing of A/D high frequencies: the Benchmark really is a benchmark for the best recordings and RF isolation; the ALLNIC seems, to my ear, to have HF distortion. The Accustic Arts, despite being softer, was the the most pleasing overall with all recordings. I have to get my hands on a Susvara Unveiled to compare vs the HE1000se's. I will try PGGB 'Aggressive' HF filtering and a custom EQ curve ...despite industry recommendations that headphone ear-gain necessitates the use of Harmon curves. Perhaps a custom curve would help extract both maximal resolution and reduce some HF brightness.