The Dan D'Agostino Progression Preamplifier volume control is realized with a stepped balanced resistor ladder, using high-linearity solid-state relays and discrete precision resistors. The bandwidth and transient response of the preamplifier circuitry are unaffected by volume setting. The Progression Preamplifier has two independent outputs that can be individually operated or used simultaneously for driving a second amplifier in a subwoofer based system. Separate for the Greatest Isolation Housed in a separate chassis, the power supply makes use of extensive electrical and magnetic shielding to keep radiated interference away from critical preamplifier circuits. Internal circuitry filters RF noise on the AC power line and compensates for asymmetric power waveforms and DC on the mains. A second DC output is included to power future Progression source components. Two analog meters, inspired by Swiss watch faces, function as signal meters during music playback. When volume is adjusted, the meter needles change to volume setting indicators. After adjustments are made, the meters revert back to signal meter operation. The meters also function as balance indicators when adjusting balance. Performance and Flexibility The Progression Preamplifier adds new features previously not included in a D’Agostino preamplifier. Most noticeably, the Progression Preamplifier features an optional digital module. The digital module adds coaxial, Toslink, and USB inputs to the analog base model. Field upgradeable, the optional digital module can be added at any time. A fully differential DAC handles PCM signals up to 24 bit/384 KHz and DSD signals up to 4xDSD (11.2 MHz). This digital module feeds a discrete, fully complementary and balanced analog signal path from input to output. Negative feedback is not used anywhere in the Progression Preamplifier, nor is it necessary. Open-loop distortion is less than < 0.006% and the open loop bandwidth extends to over 100KHz. Specifications Frequency Response 0.1 Hz to 1 MHz, -3dB / 20 Hz to 80 kHz, +/-0.5dB Signal-to-Noise Ratio -95 dB, unweighted Gain +8 or +14 dB, Switchable Finish Silver or Black with Custom Finishes Available Upon Request Distortion < 0.018% THD+N, 20 Hz to 20kHz Outputs 2 stereo pairs of balanced XLR Manual owners-manual-DDMAS-progression-preamplifier-20170913.pdf (850.42 KB) Power Consumption (at Standby) < 40W Analog Inputs 4 stereo pairs of balanced XLR, 2 stereo pairs of single-ended RCA Digital Inputs (w/DAC Module Installed) 1 USB Type A, 1 Optical Toslink, 1 SPDIF Coaxial High Resolution Images Control RS-232, 2 12V trigger outputs
