Product Overview & Specifications
The P-20 Preamplifiers elegantly sculpted aluminum case encloses a number of significant advances over the preamps award-winning P-9 predecessor in several key areas, especially with respect to volume control. A preamps volume-control capabilities are among its most critical features. In practical terms, we saw room for improvement over the already excellent P-9s volume control within the areas of transparency and noise.
Design & Features
The P-20s numerically controlled, switched-resistor ladder network features the last word in thin-film technology. In order to improve precision and lower the noise floor to the vanishing point, weve implemented a single thin-film, ultra-low-noise resistor in the signal path for each of the volume controls 0.5dB gain settings, thus permitting the listener to achieve the desired volume level in precise 0.5dB steps. As a further benefit, the listener is able to adjust any inputs level to exactly correspond with any other, thereby simplifying the matching of source-component volume levels.
The heart of the P-20 boasts an all-discrete, fastidiously precise amplifier module. Because speed is of paramount significance, weve reduced capacitive loading on the final voltage amp with the implementation of ultra-low-noise, monolithic dual JFETs, specially selected VMOS FETs, and extremely flat hFE bipolar transistors in a dual cascode configuration, all of which are combined within a driven-shield arrangement. The P-20 offers a 5MHz power bandwidth, an S/N ratio exceeding 100dB, and a dynamic range in excess of 120 dB. There are no capacitors or DC-servos in the inherently stable P-20s gain circuit.
And, in keeping with these advances, weve paid a great deal of attention to isolation. Weve covered the amplifier modules with thermal insulation along with heavy copper shields in order to avoid thermal drift or signal-degrading heating effects. Each amp modules self-contained shunt regulator further assists in isolation from power supplies. A similarly isolated floating-current source supply feeds each module to insure separation from ground-system noise.
Since all control functions are powered by discrete power supplies, the P-20s design prevents any logic circuitry clock-signal noise from ever contaminating the analog section's low-level signals. In keeping with the P-20s state-of-the-art features, we include a delightfully convenient, custom-designed remote control. In sum, the P-20s near-to-molecular clarity offers the last word in utterly transparent, organic sound in effect, a stress-free listening experience as close to live as audio permits. Better still, these features can be activated by a 12V trigger signal enabling system integration without the need for manual intervention. All that's required is a processor or receiver with a common 12V trigger connection.
- Ultra low noise 1nV/ Hz JFETs Volume control features numerically controlled
- switched-resistor ladder network with the latest in thin-film
- ultra-low-noise resistor technology
- Full microprocessor control with memory retention
- No capacitor and no DC-servo in the signal path 3 separate power supplies
- Individual audio channels are shielded with heavy copper shield with thermal barrier
- Solid stainless steel back connector panel forms a solid signal ground reference
Specifications
| Inputs | 1 XLR, 5 RCA |
| Outputs | 1 RCA, 1 XLR |
| THD+N | at 1kHz = 0.0006% at 20-20kHz = 0.003% at DC to 1MHz |
| S/N Ratio | 100dB at 20-20kHz S/N > 90dB at DC to 1MHz |
| Frequency Response | at 20-20kHz = +0.02dB/-0dB at DC to 1Mhz = +0.5dB/-0dB at DC-2.5 MHz +0/-3dB |
| Maximum Output | 7V RMS |
| Phase Shift | = 0 |
| Input Impedance | = 10K ohm |
| Output Impedance | = 100 ohm |
| Weight | 17lbs |
| Power | 120V 60Hz (100V and 240V models available) |
| Available Colors | black or silver anodized aluminum |
| Warranty | three (3) year warranty. |

