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To DSD enable the DAC2 meant not just new firmware code. To also support 384kHz PCM required new USB hardware. This even added integer support, a sound-enhancing option in Audirvana's Mac music player which the original couldn't access. For Windows users the new code means a new driver. Mac/Linux users are good to go. With these updates the blue display of the original has turned green but the original black or silver case options remain (silver leaves the signature corners black). Clint Hartman explained how they'd just come across a Chinese clone. Whilst flattery credits both brand and model popularity, cloning is identity theft and customer abuse. It also demonstrates the perpetrator's lack of confidence to make it on their own steam. What a sorry self indictment. Wankers!

Because this new module runs off USB power, a chip-based optocoupler cuts the ground connection to the computer and thus slams shut the door to computer-generated noise migrating into the DAC2 DSDse. This obviously also means that data-only USB cables are a no go. Double-header cables are fine but running their power leg off a battery supply like Bakoon's BPS-02 should be a waste of good money.


What was the genesis behind these upgrades? "The DAC2 was an industry-leading performer for the last several years. As time passes however, parts of any product tend to fall behind the curve. Typically audio products are designed such that the entire circuit board would need replacing before any changes could be properly implemented. We advertised the DAC2 as being modular or upgradeable and now deliver on just that. The changes place the DAC2 back on top where it was for quite some time. Numerous customers let us know about being curious what type of upgrade path we might offer. With so much happening on a daily basis, it is easy to overlook one's options and how they might get implemented. After hearing about all the aimless mods others were doing to our product, it just came to me one day to face this challenge and start with a clean slate. 


"We design each of our products with all this in mind but there's always a practical limit about just how significant we will go with upgrading parts of a stock unit. Here we are the experts on our own circuits. We know what to change and what not to based on where to reap the most significant performance improvements. I can’t count the times I’ve seen others implement changes and tout them as improvements when all they really did was swap parts which only had auxiliary or supplemental functions. We instead focus tactically on the bits which actually affect realistic and palpable changes.

Google Earth view on Wyred4Sound

"For obvious reasons we included the new USB interface which offers galvanic I²S isolation for PCM which now supports 384kHz and DSD and double DSD which weren't factors when the DAC2 first launched. This new platform provides driverless operation for Mac and Linux and is supplied with drivers for Windows as well as ASIO for those interested. To further improve the 'se' version, we decided to change critical analog parts for added rewards. It has been some time since we developed the converter mods for Cullen Circuits. Here I found it very rewarding to revisit old tools. The DAC2 was already heavily based on audiophile components which make up its discrete circuits. I thus had to look hard into which new parts would even make sense. Going through my old junk drawer I now came across a handful of naked Vishay Z-foil resistors and thought to try them. Holy smokes was I happy to come across such significant changes. We'd evaluated these parts for upgrades in the past but always refrained from implementing them due to their high cost. With the DAC2 relaunch the sheer volume of machines already in the field and the number of parts we'd allocate per unit became high enough to negotiate a more attractive price within our budget.  
PartsConnexion calls these "the very best Vishay resistors made for audio, in fact the highest technology resistors on the planet".
 

"As you can imagine, we were very excited and couldn't resist from going even further. Like any hifi product the power supply is the core engine of change. I’m not so sure there is any truth to the chance of going overboard with a power supply. So out went the ultra-fast bridge diode arrangement and in came the new Schottky parts. This refined DC now feeds discrete regulators rather than the noisier fixed versions from before. Having the power supply noise floor hundreds of times quieter we now had a much more accurate foundation for the analog reconstruction of the signal. At this stage the only thing to still address was the display which many had commented about. Yes it was a bit hard to make out at a distance greater than 15' which some listening positions require. To solve this and keep up with the times we went green. Although the new OLED display is more efficient, we didn't focus too much on efficiency but rather the fact that green allows for much cleaner more legible characters across distance. In addition the new display is much quieter than the original VFD because the induced pulsing of the required high-voltage charge is no longer needed. This allowed us to further reduce the audible noise floor.


"All in all this is a completely different DAC now with a seriously refined sonic presentation never mind the increased USB streaming options. Of all these improvements we never imagined that the DAC2 could still show more space, better staging or image focus. But boy were we wrong. We accomplished so much with this upgrade that it makes me extremely excited for our future!" - EJ Sarmento

Switched attenuation resistor arrays of STP-SE and STP-SE stage 2 respectively. Vishay alley!

A few weeks later Wyred's website announced equivalent stage 1 & 2 upgrade options for their STP-SE preamplifier. The naked Vishay Z-foil resistors make a mass appearance already in the first option. i.e. in "24 critical locations" but stage 2 "takes a larger leap where our attention was first directed to the resistor ladder volume control, a feature that sets it apart from the competition. Determined to optimize transparency and space, we replace 48 of the most frequently used resistors with our custom Z-foils where their accuracy becomes increasingly evident." Aside from spreading the goodies around, this development compounded EJ's quantity buy-in of costly premium parts to achieve better per-unit pricing. "Had a batch come in which was completely sold out once it landed. The next batch coming in which will field your review unit is already spoken for by a full 80% again. I wish Vishay could build these parts faster. I hate to forecast $10.000 on freaking resistors but that's the name of this game."