Review: Resolution Audio Opus 21 Great Northern Sound Mod CD Player

Category: Digital

I would like to start my review right off the bat by disclosing my past reviews and my current dealer status. I was responsible for the previous Resolution Audio Opus 21 review back in May 2003 under the moniker “Platsolos,” and now I am writing a follow-up to a modified unit. I do have the unit on display for audition.

I must admit I have been enamored with digital sound reproduction over the years for whatever reason and have continually been amazed by the sound differences that can come from differing transports, D/A converters and parts quality and construction. With that, I had reviewed numerous digital front ends from one box solutions to separate DACs and transports.

With the recent craze in ultra expensive digital sources, I started to question what can be done to, in my opinion, the best CD player under $10k? Can a modification of the Opus compete with the likes of the EMM Labs, Esoteric, Zanden, MBL, Reimyo and others? Well I can tell you right now I will never know, as I have not had the luxury of affording or being in the same environment as all these outstanding players to A/B them against each other. But I welcome any owner of these units to drop me a line, bring your unit over and A/B it. The GNSC modified RA Opus 21 is THAT good.

Choosing Great Northern Sound:
When I considered modifying the RA Opus 21 I wanted to work with a reputable company, one that is here to stay and one that backs the work through real warranties. After talking with Steve Huntley, I learned that every Opus 21 modified by GNSC comes with a backed up warranty, equal to the original RA factory’s warranty, and that Resolution Audio actually provides parts and support as needed to GNSC should a modified unit fail. Rest assured, this is not a fly-by-night modifier who is here today modifying mass market units, and then gone tomorrow.

Steve has two upgrade paths: Standard at $750 and Reference at $1500. There are differences in the extent of the modifications between the two, I chose the Reference modifications.

Sound right out of the box:
It is immediate that the change Steve makes to the Opus is apparent without any break-in. Deep 3-dimensional layering, black backgrounds with stunning resolution and detail typify the sound right out of the box. By far and away the biggest improvement is that CDs now approach the sound of vinyl to me. Previously the most analog-like digital source I heard was through a CEC belt driven transport, but this came with many and obvious faults. The GNSC Opus 21 is able to build upon what I considered the best balanced CD source I have ever heard (maintains liquidity of a CEC with the detail, snap and resolution of the finest) and adds detail, layering and amazing transparency.

Physical changes to the unit:
The modifications consist of extensive use of black gate capacitors, power filtering, power supply improvements, analog output stage modifications and extensive and strategic dampening of the chassis and mechanism. The unit is clearly heavier and has a more inert feel (mostly due to the damping of the chassis and mechanism).

Comparisons to other units:
I have yet to hear an SACD, DVD-A or CD player that can even match the modified Opus 21. The GNSC is clearly superior, even comparing CD vs. SACD. See my review on the base Opus 21 for what it already has beaten out, un-modified. I welcome anyone with any priced digital to A/B it against the GNSC Opus 21.

The changes can be summed up in the following points:
1) This is the closest to vinyl I have experienced
2) An improvement in the depth of soundstage
3) Each instrument continues to carry its own space, with even more body and fleshy tones to the instruments and voices. Acoustic guitars possess that intangible woody character; snare drums seem to resonate in air directly in front of you. Vocals are deep, breathy and
4) Black as night background, the music emanates from a 3 dimensional space
5) Increased dynamic attack and bass output
6) Staggering resolution and detail beyond reproach
7) Air
8) Air
9) Air

Final Thoughts:
The thoughts and opinions in this review are just that, my opinions and experiences. I urge anyone interested in hearing the unit to do so if you can. This is truly a player that has changed my view of what redbook can accomplish.

Associated gear
AAD Sound 7001 Monitors - $9000/pair
Audience AU24 XLR
Audience AU24 Speaker Cables
Pass Labs X250.5
Virtual Dynamics Power 3 Power Cables
Audio Magic Power Conditioner