Soulution 721 Preamplifier with 725 Upgrade - Consignment

Soulution 721 Preamplifier with 725 Upgrade - Consignment

Condition: Excellent 

Includes: Box and Remote 

SN: 0026

Made In Switzerland

Philosophy
A perfect preamplifier shows consistent level and phase performance regardless of load. At soulution we stick to this ideal without resorting to often-used compromises like high amplification with high negative feedback. The result: virtually no distortion, hum or noise, maximum channel separation and impressive bandwidth (up to 1 MHz/– 3 dB).

Design
As few components in the signal path as possible and a dual-mono layout with discrete left and right channels maximise audio purity and virtually eliminate crosstalk. Input selection (including the ground connection) is by high-grade relay. And input buffering ensures the 725 presents a benign load to source components.

Input levelling permits different source device levels to be accommodated. All inputs are monitored continually for residual DC with audiophile-grade blocking capacitors automatically switching in and out when required. In this way maximum operational safety is guaranteed. As a further safeguard the front panel display indicates when DC is present.

Volume control
The volume control uses high-precision, low-noise metal foil resistors, and controls both volume and balance. To block switching peaks during volume changes which may be hazardous to power amplifiers a second volume control with PGA (Programmable Gain Amplifier) is used. Active only when the volume is changed, it is similar to a potentiometer and enables the volume to be adjusted in smooth steps without clicks. As soon as the new desired level has been selected, the unit returns control to the precision resistors.

Output stage
Able to drive even long interconnects, the 725’s multi-stage signal amplification is similar to that of the 711 power amplifier. In most cases levels can be maintained with no further amplification of the audio signal.

The optimised circuitry is based on special power transistors which are further linearized by an analogue computing network. In this way a very fast, very precise and ultra wideband (2 MHz/– 3 dB) performance can be achieved.

Specifications