
Review sample provided by Laiv Audio
Retail price:
Harmony uDDC 849 USD + VAT (999 Euro in EU)
When I reviewed the Laiv Harmony DAC in September last year, a complete range of other Harmony products was on the horizon. With the exception of the NET2 streamer, all these products are now available.
In this review, I will cover the uDDC digital-to-digital converter.
Harmony Range
The complete Harmony range comprises the Harmony DAC, HP2A Preamp/Headphone Amp, LExt IN2 Input Extension Interface, LExt Phono Input Extension Interface, uDDC D-D Reclocker, Net2 Streamer, and GanM Mono Power Amplifiers, which were recently released. The final pending introduction is for the Net 2, which is scheduled for Q3 2025.
Harmony uDDC Description
The uDDC is an advanced digital reclocker and jitter reducer that doubles as a handy multi-input digital interface, increasing the number and type of inputs available to a connected DAC. The device is designed as the ideal companion for the uDAC, but it also works seamlessly with any other DAC featuring an I2S input.
The uDDC’s reclocking mechanism works by re-aligning the signal timing, effectively cleansing the digital signal of jitter introduced by upstream digital sources. This helps reduce jitter and improves signal accuracy before it reaches the DAC. Additionally, the µDDC features optocoupler isolation on digital outputs, which minimizes interference and ensures a cleaner signal path for an enhanced listening experience.
The Harmony uDDC’s compact size makes seamless integration into a desktop environment easy. However, don’t let its size fool you; it’s an interesting upgrade even for large, upscale systems.
The unit features discrete buttons to allow convenient direct input selection, rather than the commonly used single toggle button. The uDAC offers I2S, Coax, USB, and AES/EBU inputs. The latter is worth emphasizing because the Harmony DAC and the uDAC do not provide this input.
CNC-machined from a single block of aerospace-grade aluminum, the uDDC delivers a refined and premium-quality finish and effective heat dissipation.
The uDDC features an advanced ultra-low phase noise Femto clock and the ability to integrate seamlessly with external 10 MHz master clocks.
The uDDC also features a high-precision Field-Programmable Gate Array (FPGA) that manages complex digital signal routing and processing with ultra-low latency. Supporting formats up to PCM 768 and DSD 512, it ensures bit-perfect data handling. Complementing this is a Complex Programmable Logic Device (CPLD) dedicated to optimizing signal timing, minimizing jitter, and phase noise for precise, efficient operations.
The uDDC synchronizes and re-aligns digital signals through its proprietary FIFO buffer system, eliminating timing irregularities and jitter from upstream devices to deliver a stable and clean output.
The I2S outputs are galvanically isolated, preventing electrical interference and noise from propagating between components.
Review Context
The uDAC was connected to power and allowed to acclimatize for more than a week before serious assessments began. Even after a week, the unit becomes only barely warm.
The uDDC was listened to in the main system, which consists of the CH Precision L1 preamplifier, CH Precision A1.5 power amp, and Magico S1 MkII speakers. In addition, I also used the Apogee Centaurs.
As natural partners for the uDDC, I used the uDAC and the Harmony DAC. Digital sources include the Antipodes K50 and Grimm MU1 music servers, as well as the Aqua Diva M2 CD transport. All interlinks are Driade Flow Link Reference 808, balanced and unbalanced, and the speaker cables are Driade Flow Reference 808.
All components, including the review components, are powered by the PS Audio P20 PowerPlant.
La Diva M2 Coax
When connected via the uDDC, the Aqua La Diva M2 CD transport becomes more precise in the bass, cleaner, and more transparent overall. At the same time, the sound also becomes more delicate. The soundstage also expands in width and vividness, making the music feel more intimate and direct. Interestingly, the sound does not become controlled or analytical. It’s still as fluid, airy, and free-flowing as it was without the uDDC, but even more interesting! While the presentation is clearly different from the non-uDDC rendition, the intention remains the same, complete with all the musicality, flow, and emotional involvement. I’ve heard reclocker devices before, but they have never impressed me until now.
Oladra USB
The mighty Antipodes Oladra server (running MinimServer with MPD) connected via USB sounds remarkably robust and powerful in the bass after hearing the CD transport, but a little darker and comparatively a little sobering and down-to-earth. As fluid and musical as this server is, it is not quite as delicate, airy, and free-flowing as the CD transport. This is not particular to the Oladra, but rather quite typical of music servers compared to CD transports in general. However, with the uDDC, once again, the bass becomes cleaner and tidier, while the pacing and midrange clarity also improve, making for a more expressive delivery that allows the music to flow out of the speakers more fluidly and freely. How about that?!
Now, the server sounds a lot more similar to the CD. In fact, I needed to do a double check to ensure myself of the precise differences when using the uDDC! Well, holy moly, there are still differences: CD is slightly more fluid, and the server is slightly more robust, but these are more nuances, certainly not huge differences. Nevertheless, although one can still prefer one over the other, there is no denying that the uDDC improves both sources and brings them closer together.
Oladra I2S
Now, I wondered, would the uDDC still do the same for an I2S signal? After all, this format does not possess the USB or S/PDIF challenges. Switching from USB via the uDDC to I2S directly from the server into the uDAC, the sound was certainly still good, but it had lost a little crispness, speed, and positivity, and was now relatively more sobering. But sure enough, with the uDDC in place, with I2S in and I2S out, the pacing and uplifting positivity were fully back!
Next, I wondered exactly how USB and I2S compared. Would I2S still have a benefit over USB when the uDDC is used in between? As it turns out, the differences become very small. With the uDDC cleaning up the signal, both I2S and USB now sound so good that I can listen to them with full content. However, they do not sound exactly the same, I2S being slightly more controlled and precise than USB. This is surprising, as USB is typically the most controlled-sounding interface, and I2S in this case is derived from the Oladra’s reclocker board, which typically sounds a little smoother when used with its other outputs, such as coax or AES/EBU. Apparently, I2S behaves a little differently, at least when used with the uDDC and uDAC.
I absolutely did not expect the uDDC to have such a profound influence, but the improvement it brings is akin to stepping up one model in a product range. That said, although the uDDC brings the uDAC closer to the Harmony DAC, the latter remains considerably better.
So, what might the uDDC do for the Harmony DAC?
Eagle-eyed readers will have noticed the two stunning blocks of sculpted aluminum flanking the CH A1.5 amplifier. These are the brand-new Laiv Harmony GaNM monos, which I will review next.
uDDC with Harmony DAC
Starting with the CD transport’s coaxial output, sure enough, the uDDC does similar things for the Harmony DAC as it does for the uDAC, enhancing bass precision and transparency, and bringing the musicians closer to the listener. The impact is immediate and very audible. However, as the Harmony DAC is already very fluid and highly refined, the uDDC does not further enhance these particular aspects.
Furthermore, although the change is profound and I still prefer, in many ways, what it does for the Harmony DAC in my system, the further increased precision and subjectively leaner balance, as a result of tighter bass and a crisper midrange, can be a two-edged sword. I personally prefer a revealing and direct sound. Still, given the Harmony DAC’s inherent high precision, I can imagine some people preferring the less accurate but relatively fuller and less explicit presentation of the Harmony DAC sans uDDC, when used in a bass-shy or bright system.
When used with the Oladra server and using I2S, however, I have no such reservations, and I still find that the uDDC improves the sound of the Harmony DAC in the same way as it does with the uDAC. Somehow, it elevates the playback by increasing the pacing and injecting a more ethereal quality that can appear missing in comparison to the CD transport. At the same time, I think Oladra’s full bass and deep tonality prevent the sound from becoming lean or analytical, even when the DAC is used with the most open and direct-sounding cables.
Naturally, the influence of the interlinks and power cable should not be underestimated when making comparisons like these. I always like to use the most linear and transparent interlinks and power cables, but the uDAC’s Wall-Wart power adapter precludes the use of a better power cable. This is where the Harmony DAC has an advantage, as it can be tweaked to sound warmer (for a leaner-sounding source) or leaner (for a fuller-sounding source) by choosing the preferred cable.
On balance, the uDDC remains a must-try device; however, rather than issuing an unequivocal “buy now” recommendation when combined with the uDAC, the success of another DAC pairing largely depends on system circumstances and personal preferences.
Conclusion
The uDAC is a natural partner for the uDAC. This extends the number of inputs and adds AES/EBU. However, arguably its greatest and certainly most unexpected quality is how much it improves the sound of any source connected to any input. If you already have the uDAC or consider buying it, adding the uDDC is an absolute no-brainer. Even if you use a different DAC, as long as it has an I2S input, I highly recommend trying the uDDC.
External Links
Manufacturer: Laiv Audio