Nuforce is probably one of the few class-D manufacturer with its own patent (US patent granted in 2007) and R&D. And we use not only our own class-d design but also other chips on the market. Since we started selling our first product in 2005, we have expanded into many categories and performance level, so I can say that our experience and road map reflects where class-D is going.
As many of you have recognized, with advance in technology, each generation of class-d gets better. When we started to win over many audiophiles with our power amp in 2005, after more than 8 years, with thousands of high-end customers worldwide, there is no question that the best class-d implementation can match the best solid state or tube amp. On the other hand, commercial reality (pricing pressure) and market requirement also resulted in many class-d power amp (mostly chips) being designed for low cost, low power requirement.
Nuforce vision is to design the best sounding audio for a consumer lifestyle, whether it is for portable, entry level home use, or high-end audio. So how do we decide what goes into high-end audio and how far can we push the performance limit for a $299 (Dia) or $549 all digital power amp (DDA-100, to be released in late June) ?
To be honest, the performance difference between high-end audio and entry level priced audio is getting smaller. For example, the soon to be released DDA-100, at $549 (USD or Euro), offers 4 digital inputs (1 USB, 1 coaxial, 2 optical) and 50W@8ohm x 2 speaker outputs with high-end audiophile-grade sound quality. On the other extreme end, our Ref 18 cost more than 15X. In any industry, extreme performance and limited market demand resulted in high price (Ferrari cost 20X the price of entry level car). I will use these two products to illustrate where we see class-d going in the coming years.
How can we offer a high-end integrated amp such as DDA-100 for so little money and how far have we pushed the performance?
I would dare to say that DDA-100 sounded better than our V1 generation power amp which retails for more than $2000 8 years ago. Today, we can achieve the same performance at about 1/4 the price 8 years ago. DDA-100 uses an all digital chip so that brings the cost down significantly. Surprisingly, the performance is incredibly good after we did some optimization to the system design. The limitation with such a design is that we don't have much room to modify it or increase the power. We have to start from the ground up again if we are going to offer a higher power DDA-100. Lower price product such as DDA-100 have to cut cost whereas Ref 18 uses big and heavier chassis, with lots of shielding inside.
The bottom line for high-end Class D is that it has to keep pushing the limit, and fewer and fewer high-end companies are able to do so (either because they lack the R&D capability or are dependent on module supplier such as icepower). Class-d implementation is a lot more complex than solid state or tube.
We have to amortize the R&D cost over a smaller number of units, that added to the cost of high-end products as well.
Jason from Nuforce
) but I guess capacitors do a sort of buffering?
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