Synästec Audio Bivium ultimate preamplifier

"Using a host of cutting-edge technologies, complemented by thoughtful layout, exquisite craftsmanship and premium material, this piece of art exhibits immeasurably low distortion and an astonishing signal-to-noise ratio exceeding 116dB. Bivium is simply the quietest audio line stage preamplifier ever!"


Power of the Union

The Bivium features at its input stage a unique quad collaborated amplifier. This is an innovative collateral technology that employs four individual amplifiers working together flawlessly, delivering four times the available driving current, ultra low distortion and substantially lesser noise.

Perfect Symmetry

The Bivium audio circuit is a true balanced, dual differential configuration all the way from input to output. This means that audio signals do not go through any additional balanced-to-unbalanced converters that could induce coloration.

Minimal Resistance to Perfection

Whereas ordinary preamps use high impedance potentiometer in tens of Kilo-ohms, the stepper attenuator used in the Bivium is under 200 ohms – several hundred times lower than usual. Since Johnson-Thermal noise is directly proportional to resistance, lower impedance means lower noise. This ultra low impedance attenuator is connected in shunt mode so that there is only one resistor within the audio signal chain, rather than dozens of resistors and relays in series as featured in other connection modes, such as the “R2R” network. Low current noise, low temperature coefficient precision resistors are employed, and two attenuators are used in each channel for a true balanced operation.

Redundance Hurts

Excessive gain will bring up the system noise floor, worsen signal clarity. The Bivium eliminates excessive gain by allocating two separate sets of amplifiers – one a unit gain buffer and the other a fixed gain amplifier, and each optimized according to their specific operation conditions. When listening at low or moderate volumes, the buffer section will be used. When you turn the volume up to certain level, it will automatically switch – seamlessly and imperceptibly – to the fixed gain section. Using this adaptive gain management, the Bivium produces equally excellent performance at any volume level.

The audio circuit board is made from Roger material RO4003 which features excellent high frequency performance due to low dielectric tolerance and loss.

Pure Source

The Bivium uses ultra low noise voltage regulators built with discrete transistors, which only exhibit 1/10th of the noise compared to their so-called low-noise IC counterparts. Dedicated regulators are strategically located right alongside each critical amplifier circuit.

Ideal structure

Delicate electronic parts are installed in a massive solid aluminum housing, an ultra stable platform against EMI and vibration. Every functional block has individually isolated compartments for zero interference. Noisy power transformers and AC power circuit are installed in separate housing, which is also machined from a solid block of aluminum.


3 symmetrical
2 asymmetrical
1 symmetrical
1 asymmetrical
Frequency response:
10 Hz to 185 kHz (+0/-0.5 dB)
<0 .0005="" 20="" hz="" i="" khz="" to="">
Signal to Noise ratio:
>116 dBA
Channel separation:
> 120dB
Input impedance:
20 kOhm
Output impedance:
100 Ohm
Power consumption:
28 Watt
21.7kg net
400 mm x 307 mm x 87 mm (W x D x H)