Full 6Moons Award Review : Soundastic Reference Integrated Amplifier

The Soundastic Reference is a high-end audiophile amplifier hand-made in Poland by dedicated craftsmen. Beautifully designed inside and outside.

Soundastic Reference is a dual mono audio amplifier, manufactured in line with cutting edge technologies and worldwide standards of quality and reliability. 

An anti-magnetic alloy casing ensures significant resistance to external interference and the power supply consists of two Thyssen 500 VA toroidal transformers.

The transformers are characterised by low level loss and well as high levels of inductance, small in size they have a very low magnetic dispersion field. They have been installed on anti-vibration bases and secured by means of a special epoxy mixture, while the fixing to the amplifier chassis has been carried out using a copper sheet with thickness of 3 mm. 

Output transistors have been installed on a 15 mm thick aluminium plate in order to eliminate the residual vibrations caused by the transformers. 

The front plate is made of  aviation-grade aluminium alloys. The precisely optimised convection cooling system allowed to reduce the size of the amplifier.

A new delayed transformer activation system (soft start) was designed, including an anti-interference filter. Such a solution eliminates overvoltage when turning the amplifier on, as well as the adverse impact of the above on the lifetime of electrolytic capacitors. 

The rear plate of the amplifier has been fitted with speaker terminals, separate RCA sockets, and XLR inputs (professional Amphenol sockets). The other RCA sockets are gilded Japanese Jalco sockets. 

Amplifier front: mains switch and input selector are manufactured by C&K, and the motor-controlled volume potentiometer is the Blue Velvet Alps model, enjoying a great deal of respect in the world of audiophiles which also performs the role of a passive preamplifier. 

Soundastic Reference features record player inputs for MC and MM inserts, in which THT (discreet) elements have been applied. The RIAA curves have been modified by adding an additional 3.2 s (Neumann) time constant, which led to achieving greater spatiality of the musical image. In each situation, both when using a record player and at each of the in line input type.

The amplifier is characterised by its approximation of the appreciated vacuum tube sound, while at the same time retaining all the best features of a transistor-based amplifier, such as speed and control over low frequencies. The final path of the signal is the two power amplifiers in a balanced system, powered by electrolytic capacitors of the Nippon Chemi-Con company, having a total capacity of 48 000 F. The design of the power amplifiers is based on the original patent of the Soundastic company, RP No. 176514.

Within the signal channel, the amplifiers do not feature any capacity element (capacitors). It has been designed with the use of only the JFET transistors and a symmetrical input. This ensures sound neutrality that is sought-after among the highest class audio devices. The end transistors are two pairs per each channel (8 pcs in total) of American MOSFET transistors from the International Rectifier Company. 

The remote control weighing 0.370 kg is made of solid aluminium.

Specifications

• Power: 2 x 140 W/8 (CLASS AB)2 x 260 W/4 (CLASS AB)
• Minimum impedance load: 1 (instantaneous)
• Power consumption: STATIC 40 VAPEAK 1200 VA
• Distortion THD: 0.05% at 1 W / 8 0.02% at 120 W / 8
• Frequency response: 5 Hz 100 kHz 3 dB / 1 W / 8
• Non-linearities in the frequency band: 10 30,000 Hz: ± 0.01 dB
• Slew rate: 150 V/s
• Signal noise ratio: 130 dB (IHF A)
• Inputs: 4 x universal RCA, XLR Amphenol, Separated CD / DAC RCA, Phono MM RCA
• Sensitivity of inputs: 500 mV universal inputs and dedicated CD / DAC, 500 mV XLR input, 3 mV MM input, 0,2 mV MC input
• Impedance inputs: 100 k; universal inputs and CD / DAC, 22 k XLR, 47 k MM, 100 MC
• Potentiometer (volume): the highest precision model the Alps Blue Velvet
• Transformers: 2 x toroidal, 500 VA each
• Capacitors filtering the supply voltage: 4 x 12 000 uF Nippon Chemi-Con
• Advanced protection system: against short-circuiting of the loudspeakers and a stream of DC voltage output
• Remote control: RC5 code (volume)
• The DM 250 amplifier fulfills all requirements and standards valid in the EU
• Net weight: 16 kg
• Dimensions: 430 x 95 x 358 mm
• Manufacturers warranty: 24 months