Naim NAIT integrated amplifier 1989 Measurements
Measuring this amplifier provided some interesting data. The smooth treble performance of the NAIT 2 that I liked actually appears to be due to euphonic coloration. Looking at the NAIT 2's frequency response (fig.1), a rolled-off high end is apparent. In fact, the response was down nearly 2dB at 20kHz.
Fig.1 Naim NAIT 2, frequency response at 1W into 8 ohms (0.5dB/vertical div.).
Not surprisingly, the NAIT 2 had the lowest power output of the group. A 1kHz sinewave clipped at 21W when driving an 8 ohm load (13.2dBW), and at 33.5W into 4 ohms (12.3dBW). The NAIT 2's RIAA equalization error plot (fig.2) showed a slightly rising response above about 2kHz. This characteristic should somewhat mitigate the line section's high-frequency loss when playing LPs.
Fig.2 Naim NAIT 2, phono input RIAA error (0.5dB/vertical div.).
Interestingly, the HF rolloff will be most apparent when playing CDs. The net effect of a rising high end in the phono section and a falling HF response in the line section will be to soften the sound of CDs without affecting the phono input as much. Was this a conscious design decision?—Robert Harley