Litt info fra NuPrime:
After consulting with the chief engineer, I have more details and very interesting information.
A class-D amp product is consisted of three main components:
Preamp Stage, Class D Stage, Power Supply
(note that this Preamp Stage is not the volume control preamp, but an integral front-end of the Class D amp design)
Preamp Stage design is made of
(A) Op Amp or discrete transistors and in NuPrime's designs there two types: (B)ULCAM (Ultra Linear Class A Module) and (C)SECAM (Single Ended Class A Module)
Practically all the amp products on the market use Op Amp for preamp stage. Only a few very high end products use discrete transistors design. This is hard core analog design. Tube or solid state amp is basically one BIG (giant size) transistor. Now you can see why we could reproduce tube or solid state sound, while keeping the advantage of class D speed and dynamic.
Class D power stage design can be Half Bridge (H) or Full Bridge (F)
Power supply can be Switching (S) or Linear (L)
Now here's where things get really interesting.
IDA-16 = A+H+S (Op Amp + Half Bridge + Switching) for clean, fast, and powerful
ST-10 = A+F+L for clean, fast, smooth and refined
IDA-8 = B+H+L for a little more warmth and fast
STA-9 = C+H+L for tube-like sound, warmth, and fast
K-38 = C+B+H+S
There are more combinations that we can do here: C+H+S or C+B+F+L or C+B+F+S
Chief engineer said there could be literally unlimited number of topologies using transistors for the preamp stage, but to get something good is very tedious work.
I think NuPrime is the only company in the world that can offer this type of ultra high end custom design at budget price.
We plan to introduce Custom Audio (rack mount) very shortly for customers who order large number of channels (> 10) to do custom selection. For example, you might want to have 10 channels of IDA-16 and STA-9 combo sound, but only need 50W per channel (multi-room high end back ground music). We can mount the preamp stage of STA-9 with the Class D power stage of IDA-16, and one 500W SMPS.
Or if you are a speaker company, we can custom design amp module for your active speaker.