I found this nice write up of the evo one's is it accurate on the description?
Excerpts from review, translated:
<<<Input impedance up to 1MΩ
The first is the input stage. The Evolution One (hereafter referred to as EVO One) advertises that the newly designed input stage has an input impedance of up to 1 MΩ. What are the benefits? In general, the higher the input impedance of the amplifier, the better, so that even if the signal sent from the front end is extremely weak, the back end can be easily driven with lower distortion and phase delay. EVO One's input impedance is up to 1MΩ, making it easy to match any front-end equipment. However, the input impedance is not a big deal. If the technology is not in place, the high input impedance is likely to cause interference, and the noise of the front end is also absorbed. The result is not affected but the first one is harmed. Everyone knows the benefits of 1MΩ input impedance, but usually only the noble machine can do it. EVO One uses computer simulation when designing the input stage. It is the first Class D amplifier with 1MΩ input impedance, and it may be unique in this price band.
Then look at the EVO One class D amplifier circuit, the biggest feature is that the switching frequency of the crystal working up to 700kHz, so the sound is more round, delicate, and better resolution. What is the switching frequency of the crystal? This starts with the way D is amplified. Many people mistakenly think that Class D is a Digital (digital) amplification. In fact, Class D uses a power crystal as an amplifying component. It is still analogously amplified, but the crystal works in a fully open and closed state, so the efficiency is so high. The above 700 kHz refers to the switching frequency of the power crystal switch. Generally, the switching frequency of the class D amplifier is about 300 kHz. The higher the frequency, the more likely it is to generate heat and is unstable. However, the NuPrime pulls the switching frequency to a multiple of others, and remains stable and does not generate heat, which is the advantage of its technology. unique.
The power supply is switched to a traditional linear power supply.
The power section is also a major change. In the past, Reference 20 (hereinafter referred to as R20) used a switched power supply, and EVO One switched to a conventional linear power supply. The switching power supply has the advantages of small size and high efficiency, but the operating frequency is high, and the high-frequency noise is easily generated. The sound is not afraid of large size, not to mention the EVO One's input stage and Class D amplifier circuit is not large, the remaining space inside the chassis to accommodate a complete linear power circuit is more than enough. EVO One uses a toroidal transformer, the specifications are tailored to the requirements of EVO One, and the performance is more in line with the requirements. In addition, the toroidal transformer and the rectified current are additionally placed in a rectangular closed casing, which is completely isolated from the power supply filtering, input stage and power, etc., to prevent leakage of magnetic leakage and interference of any noise. The power supply filter is composed of a dozen filter capacitors, which can combine high speed, high capacity and low internal resistance. >>>>