SW1X Audio Design DAC II

DAC II is based on 2 x PCM56 DACs- probaly the most refined sounding R2R DACs ever created. It come equipped with more sophisticated power supplies and powerful 6N6P/6N30P/5687/E182CC valve output stage with 6X5GT (or 5Y3) valve rectification. The DAC II has a similar analogue & musical character akin to DAC I but with a step up in low level musical refinement and presentation on another level. The circuit design is pure and elegantly simple with only one decoupling capacitor per channel in the signal path. Everything from input to output, including the mains inlet, the whole signal path is wired with specially selected SW1X copper conductors & dielectric- the same ones that are employed in our Genesis and Opus cables.

The DAC II is currently available in STD, SPX or Balanced versions.

SW1X Audio Design™ DAC II Features:

• Pure NOS (Non oversampling – Zero Digital Domain Filtering) Design
• Selected and Harmonically matched Component & Material Quality
• Based on 2 x PCM56P K – the most refined 16Bit R2R DACs ever produced
• Active I/V conversion via a special transistor (with less than 10 Ohm input impedance)
• Pure Class A, Anode Follower, Zero Negative Feedback, Single Ended Valve Amplification Topology
• 6N6P Double Triode Driver Valve Output Stage
• Valve rectified CLC (choke filtered) B+ Power Supply
• Discrete Transistor, Shunt Voltage Regulated Low Voltage Power Supplies
• 2 x EI core Mains transformers for Split Dual Power Suplies of Digital and Analogue
• SPDIF input supports up to 24Bit/96kHz

Specially Selected and Harmonically Matched Component & Material Quality

• M6 grain orient EI core Mains Transformers & Chokes (SPX version)
• Internally wired exclusively with our SW1X Magnum, Genesis and Opus conductors of various geometry (single strand or Litz)
• AN Copper Foil in Oil Signal Output de-coupling Capacitors (SPX version)
• AB 2W non-magnetic Carbon film Resistors in selected places

Tube Compliment

STD (SPX) Version: 1 x 6N6P, 1 x 6X5GT(6C4S) or 5Y3 SPX version
Balanced Version: 1 x 6N6P, 2 x EL82, 1 x 5U4GB

Note: Due to SW1X Audio Design’s ongoing research and development process, specifications are subject to change without notice.

Specifications

Dimensions: Height (mm) 140 x Width (mm) 350 x Depth (mm) 410

Weight (kg): 9.6

Max Power Consumption (W): 18

Output Noise, Unweighted (mVrms): < 0.5

Output Impedance (K Ohms): <1

SW1X Audio Design™ DAC II Balanced

The Balanced version is a top of the line DAC II and a smaller brother to the DAC III Balanced.

Similar to the DAC III Balanced, DAC II Balanced comes equipped with a EL82/EL84 power tube output stage. The step up in transparency over the STD & SPX versions is provided by a signal output transformer (OPT) de-coupled power tube output stage driven by the active I/V conversion stage for an even more dynamic bite.

Also available in Balanced Special version with 6V6 tube output stage similar to the DAC IV.

SW1X Audio Design™ DAC II Balanced Features:

• Pure & Elegant NOS (Non oversampling – zero digital domain filtering) Design
• Balanced (& Single Ended) Signal Output Transformer de-coupled Valve Output Stage Topology
• EL84 Power Output Tubes, Zero NFB, Class A, Valve Output Stage
• Discrete Transistor, Shunt Voltage Regulated Low Voltage Power Supplies
• 5U4GYB/5R4GYB Directly Heated Valve rectified CLC (choke filtered) B+ Power Supply
• Digital Input supports up to 24Bit/96kHz S/PDIF Signal Input

Specially Selected and Harmonically Matched Component & Material Quality

• SW1X Audio Design™ Copper wound Super HiB DC core Signal Output Transformers
• M6 grain orient EI core Mains Transformers & Chokes
• Internally wired exclusively with our SW1X Magnum, Genesis and Opus conductors of various geometry (single strand or Litz)
• AN Copper Foil in Oil interstage signal de-coupling Capacitors
• AB 2W non-magnetic Carbon film Resistors in selected places

DACs made by SW1X: What is different about them?

There are multiple factors, which help to explain why our DAC products can convey the low level musical complexity and the fine spatial nuances that other DACs struggle with. Amongst other things our products intentionally do not have “bells and whistles”- load of features that most mainstream DACs showcase. The features may make the product stand out being more attractive, helping to sell a product but in the end come at the cost of sound quality. The features that contribute to destruction of musicality in a high performance audio product are but not limited to displays, meters, volume controls, switches, buttons and relays, multiple in- and outputs and last not least vast compatibility to all possible media formats and standards, just to name a few.

The mentioned features in most cases either add no value to sound quality in best case scenario or simply irreparably destroy musicality. Apart from that, they also do have the tendency to come and go with fashion. The problems is that once those features are out of fashion, what remains is a lifeless sounding product, which eventually ends up being for sale. Below are some of the key differences between SW1X and products of our competitors:

We believe that instead of spending money on the non-essential & useless features, one is better off investing money on R&D, materials & components that contribute to reproduction of finest nuances of music. All SW1X DACs are digital-filterless designs, i.e. there is no over-sampling, no jitter reduction, no noise-shaping and no re-clocking. Since all our DACs are designed to operate without any digital filtering or any kind of digital signal manipulation that is required for over-sampling, all filtering is done in the analogue domain for the best possible signal integrity. Our finest DACs employ highest quality TDA1541, PCM56 & TDA1543 converter chipsets, well known for the their analogue sound character, solely because we found them to be the best sounding available (yes, even much better than the any more modern 24bit or 32bit versions!). So, when the fashion is gone, our products are still making music, therfore making the SW1X DAC products time-less and more valuable. In other words we choose to focus on music, focus on the factors that really matter in music reproduction, optimized for a single format (PCM) and intentionally omitt the fashionable features and other feature inheriting factors that may be contributing to convenience but are counter-productive to the quality of music reproduction.

Our DAC products may look simple because absence of the extensive list of “bells and whistles” because they are optimized for high performance music reproduction and only for that one purpose. The key being here- everything designed to be really elegantly simple, where each component is not too much or too little and is optimized for each other to work in harmony. One of the main factors is the elegant circuit design for both digital and analogue output stage. Digital side is powered by a discrete transistor shunt regulated power supply, not the usual 3 legged- L78xx type integrated voltage regulators as found in products of our competitors. The other factor is that the amplification of the analogue signal performed by a tube output stage, which is single ended, Class A, without any negative feedback loops, powered by a tube rectifier. In between there a discrete I/V conversion interface with directly connects DAC output to the grid of a powerful driver or power output stage tube.

The last but not least important factor is the combination of our elegantly simple circuit design with the finest specially selected components & materials, which are just as important as the circuit design. One has the option of choosing between 5 differnt performance levels and STD, Special and Signature versions. While the Special and Signature version already are full of finest specially selected materials & components, the more basic STD version offers high quality materials & components, which can be upgraded with extras that is also being offered as an option.

On contrary to SW1X DAC designs, all on the market available over-sampling and up-sampling DACs employ dramatic signal modifications in form of noise-shaping (read more about it in an article here) or some other form of signal manipulation, which kills the musicality and buries it with op-amps or transistors which operate in complex negative feedback loops. Most of those DACs (and other products) out there are either too complex & over-engineered (computer type with many low quality components & materials) or too simplistic using off-the shelf solutions (lacking any creativity) or using low quality components & materials or a combination thereof. These DAC products have a lot in common- they are usually loaded with features such as inputs and outputs, displays etc. – a sign that they were designed by electronic engineers, not musicians. The consequence is that they may look all very different but they all do sound essentially very similar: flat, synthetic and lifeless- where some DACs may sound a bit better than others in some departments. Some manufacturers try to differentiate themselves from the rest by either not disclosing what integrated converter circuit is being used or by a FGPA (field-programmable gate array) type of a DAC, which is nothing but a programmable IC chip, programmed with custom signal manipulation algorithms- a feature borrowed from computers but in essence not sounding much differnt from the rest.

Overall, the major difference to most common mainstream DACs is that our DACs are designed by a team of creative engineers with musical education background and not by electronic engineers who understand only textbook circuit designs and nothing beyond that. We purposefully moved away from the so called “mainstream approach” (make the product look attractive above everything) and adopted a radically different approach (focusing on music, our way) in designing audio equipment. We hope that this approach is not offending anyone but this is crucial to sound quality and music reproduction- the only feature that really matters in the long run after all.