LAiV HARMONY µDDC

A few weeks later we return to talk about a product from the Singaporean company LAiV whoseHarmony DAC andHarmony µDAC we have already tested. Two digital analog converters that convinced us in terms of build quality and sonic result. Today we tackle a DDC, which stands for Digital to Digital Converter. To be honest, this acronym is a bit perplexing, at least at first. Why would anyone want a digital to>digital conversion? There are several good reasons, and the LAiV HARMONY µDDC featured in this test provides us with the cue to talk about this type of device that has been enjoying some success for some time now in the varied landscape of digital audio or Computer Audio as it may be called.

The Re-clockers

Let’s try to frame the issue: since its first, tentative appearance dating back to the late 1990s, USB has become the de facto connection for everything from rechargeable screwdriver drills, to cameras, to watches, to computers, but also in the area of digital audio that we are most interested in. Personally, I remember first coming across this type of connection in 1998 when I bought my Apple iMac G3, which was the first mainstream product with a USB connection. At that time the Universal Serial Bus standard replaced all the legacy interfaces that equipped computers at that time such as RS-232 serial, the ADB port for keyboard and mouse, the SCSI port for hard disks, etc. USB was quickly adopted by the computer world and then began to expand to all other areas of Consumer Electronics, including audio. However, USB was not designed to transmit audio signals. Nevertheless, the fact that most laptops can send digital audio via this type of connection implies that it has become the way music is transmitted in most cases in spite of its being far from perfect. Those who have ventured into DIY audio server building know how much effort needs to be put into making the standard USB outputs on PC motherboards sound good and how dedicated USB/PCI cards can elevate their overall performance.

What then does a reclocker do? Basically it stores the incoming audio signal in a buffer and reconstructs the Clock part of it thanks to a very high-precision OCXO clock, based on an oscillator with a minimal error rate, making it considerably more accurate than the clock found in all USB sources and most DACs. But why do DACs benefit from an external clock when they already have one on board? Basically because if the incoming signal is clocked at exactly the right frequency and with minimal errors, it requires less processing power which leaves more resources free to handle the conversion process. In doing this reclocking operation typically these devices also perform the task of galvanic isolators and noise reducers.

The cheaper competitive products tend to do the job of adigitalhub with many inputs and outputs, as opposed to those more avowedly devoted to the High End segment that sometimes have only one input and one output. To the first family belongs, for example, the Mutec MC3, which can also enter USB but favors AES/EBU and S/PdIF for output. To the second belongs instead theInnuos Phoenix which enters and exits only in USB.

Harmony µDDC: Description.

The HARMONY µDDC is a very advanced digital reclocker as well as jitter reducer, which also performs the function of a multi-input digital interface. With this in mind, the device increases the number and type of inputs available compared to the DAC connected to it. If only because of the similarity on an aesthetic level, the device is designed to be paired with the µDAC werecently tested , however, it also works perfectly with any other DAC as long as it has an I2S input such as the Pro-Ject Pre Box RS 2 we employed during our test.

The LAiV HARMONY µDDC has I2S, Coaxial, USB and AES/EBU inputs; I point out that the latter is not present on either the Harmony DAC or the µDAC. Selection is made by acting on physical buttons located on the top panel. There is no remote control in the package. The shape, as anticipated, is almost identical to that of the µDAC and is based on the use of a single block of CNC-machined aircraft aluminum that also performs an effective heat dissipation function. The µDDC is offered in the two refined finishes Black and Silver, both of which are of high quality. The compact size of the Harmony µDDC suggests its use in a desktop environment, perhaps together with its reference DAC. However, one should not be constrained by the form factor: in fact, it is an interesting complement even in the context of large, high-end systems.

As with all products in this category, the reclocking mechanism of the LAiV HARMONY µDDC works by realigning the signal timing, thereby effectively cleaning up the digital signal from jitter introduced by upstream digital sources. This helps reduce the overall jitter and improves the accuracy of the signal before it reaches the DAC. I think it is useful in this context to mention that the choice of output in the I2S format alone is entirely consistent with these premises. Unlike, for example, in the USB connection where the clock signal and data are carried by the same pair of wires (the other two being 5V and ground), in the i2S connection over HDMI the clock and data travel on separate connectors, thus avoiding the de-scramble stage before the DAC. I also want to point out that the µDDC has galvanic isolation on the digital outputs, which minimizes interference and ensures the cleanest possible signal path preventing the propagation of electrical interference and noise between components.

The unit is equipped with an advanced Femto clock with very low phase noise. However, thanks to a dedicated BNC port, it can be connected to external 10 MHz master clocks. Inside the µDDC we find a single PCB on which stands out the presence of an ALTERA Cyclone IV Field-Programmable Gate Array (FPGA) that handles routing and processing of complex digital signals with ultra-low latency. There is also a Logic Programmable Complex Device (CPLD) dedicated to optimizing signal timing, minimizing jitter and phase noise. To perform synchronization and realignment of digital signals, the LAiV HARMONY µDDC uses a proprietary FIFO(First In, First Out) buffer system, eliminating timing irregularities and jitter from upstream devices to provide stable and clean output. Supported formats are up to PCM 768 and DSD 512 with bit-perfect data handling.

Harmony µDDC: Listening

Having the LAiV Harmony µDAC still available in the listening room, it was entirely consequential to use it for listening tests of the LAiV Harmony µDDC. However, we also wanted to try it with another DAC, and the choice fell on the Pro-Ject Pre Box RS 2, which was then the only one we had available with an I2S input. On the source side, the Volumio Rivo Plus came to our aid, which has outputs compatible with virtually all the inputs of the LAiV µDDC, including I2S over HDMI, which it hooked up without hesitation. We also used a music server equipped with a JCAT USB card and custom made power supplies on which runs the Audiolinux operating system with MPD running. Source side the LAiV µDDC was seen by Volumio, Audiolinux and Roon as any DAC.

My first listening impression was related to the broadening of the sound front that the Vivid Audio Kaya S12s driven by the Canor Virtus i3 were able to reconstruct. The difference between with and without the LAiV µDDC is perceptible without any uncertainty. The sound front expands eventually extending far beyond the speakers and much deeper, with an articulation of space that was missing before. I would be inclined to say that this aspect is made more apparent by virtue of better separation between instruments. To make an analogy that (perhaps) might clarify the concept for some, it is as if you were using the Contrast Mask filter on Photoshop that increases the sharpness of an image by increasing the contrast along the edges of objects. There adjacent color fields, here adjacent musical instruments, are better defined by making it easier to focus and separate them. The second aspect I noticed concerns the definition of transients. I especially realized this with several solo piano and acoustic guitar tracks. It is as if the attack of each note was more defined and “sculpted” in space. I suppose the credit here goes to the improved overall timing , but also – probably – to the reduced noise level that allows weaker signals to be reproduced with greater clarity and evidence. In general, compared with operation without the µDDC, the bass range becomes cleaner and tidier, while the rhythm and clarity of the midrange also improve. Overall, I would say that the result is in favor of greater overall expressiveness of the sound emitted by the playback system.

An interesting aspect of this test involved comparing the different inputs, obviously with the same number of files running. For the umpteenth time the assumption held by many to be true: “…it’s only zero and one anyway, so it’s impossible for there to be differences,” turned out to be wrong. Of course we are talking about nuances, about details, however, the differences are there indeed. In particular, it seemed to us that in use with the Volumio Rivo Plus the best performance was with AES/EBU. While the USB input of the Italian streamer proved to be less performant than that of the JCAT PCI/USB card that equips our server with the same track running. Also very good was the quality exhibited by the I2S connection in both input and output, which seemed to me to sound lighter but also brighter than the USB.

Finally, one thing that stunned me about this test concerns its conclusion, that is, the moment when I felt I had finished critical listening and removed the LAiV µDDC from the system. There, resuming listening without it was shocking. It was as if I had taken a foothold off the house of cards. Everything collapsed mercilessly. For goodness sake, I certainly do not mean to say that listening had become unpleasant, but it certainly completely lacked the magic that had made it an engaging and exciting experience just moments before.

Conclusions

It does not take an expert reviewer to conclude that the LAiV HARMONY µDDC is the natural partner of the µDAC. It certainly expands its connectivity and adds AES/EBU. However, it would be reductive to limit it to these merely utilitarian aspects. The greatest quality of µDDC-and for yours truly also the most unexpected-is how much it enhances the sound. This applies to the µDAC but also to any other source connected to it via one of the various inputs. So, if you already have a µDAC or if you are thinking of buying one, adding the µDDC is an almost compulsory choice that can, however, fortunately, also be put into practice at a later date, thus going to constitute an excellent upgrade. Should you use a different DAC instead, as long as it has an I2S input, the advice is to try the LAiV HARMONY µDDC anyway. There is a very good chance that you will be charmed by it.

Giulio Salvioni

Technical Specifications

Product Type: Reclocker, Galvanic Isolator
Supported sampling rates
- USB-B : PCM 768kHz DSD512
- I2S : PCM 768kHz DSD512
- Coaxial / AES : PCM 192kHz DoP64
Inputs: (1x) USB-B, (1x) I2S via HDMI, (1x) AES, (1x) Coaxial, (1x) BNC 10MHz clock input
Output: (1x) I2S via HDMI
Power ports (1x) USB-C, (1x) DC jack

General