Struss Audio Ultimate: Class AB Amplifier

Designers of Struss Audio have once again reached a new level on their way to perfect sound. The Ultimate amplifier is more subtle and noble, clear and spatial, powerful and confident. Anyone looking for the full sound of outstanding power, consistency and musicality – will find them in this device. The Ultimate is an integrated amplifier with the possibility to use the preamplifier and power amplifier separately. It has been designed in a dual-mono system (balanced), which is an extension compared the previous model. It features two very efficient transformers. They are magnetically and electrostatically isolated, each with a power of 600W. The amplifier receives enough power to drive any speaker. The power of 250W at 8 Ohms makes the Ultimate a beast. Both channels work in a balanced configuration. There is no coupling capacity in the whole acoustic channel. It’s a clean DC circuit. The amplifier has been built in the J-FET / FET technology. Dynamics and speed are features you will immediately notice.

The preamplifier is a new solution. It was decided to opt for a passive circuit that supports all linear inputs. It transmits the signal from a CD player, DAC or streamer through the volume control directly to the power amplifiers. The passive preamplifier design has been maximally minimized. The Ultimate uses an advanced constant input impedance, high-sensitivity circuit that matches the line input specification. A turntable can also be connected. With both MM and MC cartridges. This part of the preamplifier circuit, similarly to the linear one, consists only of discrete elements. The phono section will surely provide an unforgettable experience for fans of analogue records.

The Ultimate also means:

Massive housing optimised for the presence of resonances
Shortest possible signal paths
Magnetically and capacitively neutral electrical system
Full security and protection for your speaker outputs
Enhanced HPCS system (Struss Audio’s patent)
High quality RCA, XLR and speaker jacks
Metal remote control
Processor isolated from the signal path for remote control

The Ultimate is an innovation that is in line with the classics. The task of the amplifier is only to deliver a perfect musical message. The construction has only the necessary features, because the most important are the acoustic qualities. It’s a very accurate sound with a real rendition of the space and atmosphere of the recording. It is distinguished by great dynamics, tonal balance and an exceptional, intimate aura which it generates from the first bars. This makes the Ultimate an amplifier with the highest sonic parameters. For those who love the charm of the lamps, but are looking for a strong amplifier transistor, the Ultimate is an excellent choice.

Specifications

Power:	2 x 250 W/8 Ω (CLASS AB) 2 x 400 W/4 Ω (CLASS AB)
Minimum impedance load:	1 Ohm (instantaneous)

Power consumption:	STATIC 40 VA PEAK 1200 VA
Output impedance:	0.20 Ω
Distortion – THD:	0.05% at 1 W / 8 Ω 0.015% at 245 W / 8 Ω
Frequency response:	3 Hz – 100 kHz – 3 dB / 1 W / 8Ω
Non-linearities in the frequency band:	10 – 30,000 Hz: ± 0.01 dB
Slew rate:	200 V/μs
Dynamics:	135 dB
Signal – noise ratio:	130 dB (IHF – A)
Inputs:	5 x universal – RCA XLR Amphenol separated CD / DAC – RCA WBT phono MM – RCA input power amplifiers – RCA

Output	Passive preamplifier – 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 0.500 V – power amplifiers
Impedance inputs:	100 kΩ; universal inputs and CD / DAC 22 kΩ XLR 47 kΩ MM 100 Ω MC 47 kΩ power amplifiers
Potentiometer (volume):	the highest precision model the Alps – Blue Velvet
Transformers:	2 x toroidal, 600 VA each
Capacitors filtering the supply voltage:	8 x 12 000 uF – Nippon Chemi-Con
Advanced protection system:	against short-circuiting of the loudspeakers and a stream of DC voltageat the output
Remote control:	RC5 code (volume)
The DM 250 amplifier fulfills all requirements and standards valid in the EU
Net weight:	19 kg
Dimensions:	430 x 102 x 338 mm
Manufacturer’s warranty:	24 months