Cranbourne Audio Camden 500-series Pre Amp. Latest model with one signal/clip light. Camden 500 provides the utmost clarity and detail when it is most required. Its custom’Camden’ topology achieves stunning low-noise and low-distortion performance: -129.8dB EIN (150ohm, unweighted) and THD+N as low as 0.0002%. It also sets a new standard for frequency and phase linearity: ±0.7dB frequency response from 5Hz to 200kHz at max gain and.