Dan D'Agostino Pre-Amplifiers

Progression Pre-Amplifier
Performance and Flexibility

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.

Advanced Control

The volume control is realised 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.

Momentum HD Pre-Amplifier
Drive and Detail for All Music

The subtleties of voices were rendered with a lushness and richness that were simply unattainable previously. Full development of what has become the Momentum HD Preamplifier started immediately. Ultimately, the HD moniker was selected as it best describes the improvements achieved in the new model. The new HD signifies the high dynamic and high definition improvements that have been accomplished in this substantial upgrade. Beyond the input stage, the new Momentum HD Preamplifier incorporates advancements in the power supply, audio circuitry, and control sections.

Advancements in the audio circuitry, power supply, and control sections are incorporated in the new Momentum HD Preamplifier.

Balanced Circuits for Maximum Bandwidth.

Like the Momentum amplifiers, the Momentum HD Preamplifier uses a complementary balanced circuit topology for maximum bandwidth and low noise. Its audio circuitry is fully discrete, with no op amps or integrated circuits. A Zero-feedback design assures the most musical sound quality. Volume adjustment is made through a resistor network governed by an optical controller —the cleanest, most transparent possible method of controlling volume.

Detail and Richness Throughout the Musical Range

A completely new discrete differential FET input stage features two current sources per leg and an input impedance greater than 1MOhm. This ultra-high input impedance isolates the input stage and thus the entire audio signal path from external variables.

This new input stage started as an engineering exercise that delivered exceptional results. Fine-grain detail and delicate musical shadings are rendered with a lushness and richness that were simply unattainable previously.

Striking Dynamics

Housed in a separate chassis for maximum isolation, the Momentum HD main power transformer is 33% larger as compared to the original Momentum Preamplifier. A unique winding technology, first employed in the Momentum M400 amplifier, delivers greater power output from the same footprint. Separate supplies power audio and control circuitry, so the control circuits are completely isolated from the audio circuits. Internal circuitry filters RF noise from the AC power-line and compensates for asymmetric power waveforms and DC on the main power line.

Taking advantage of the increased power supply capability, the output stages are now operating at a 36% percent higher voltage. The increased output voltage has opened up the dynamics on both the micro and macro level with contrasts striking in their speed.

Advanced Remote Control

Also new is the Bluetooth technology featured in the included remote control. The Bluetooth backbone extends the range of the remote by a factor of five and eliminates line of sight limitations that are inherent in IR remote controls.

Newly designed tone and volume control circuitry increases range and precision in both circuits.

The styling of the Momentum HD Preamplifier perfectly complements the Momentum M400 and S250 amplifiers, with copper accents matching the amplifiers’ unique copper heat sinks. The meter on the front face of the preamplifier indicates volume setting, polarity, and mute status. Front selector buttons illuminate indicating which input is active.

Existing Momentum Preamplifier owners will be able to upgrade to the new Momentum HD Preamplifier electronics enhancements.

Progression Pre-Amplifier

Momentum HD Pre-Amplifier