ubiqaudiolab 300B Ubiquitous hybrid preamplifier was developed exclusively with the legendary Western Electric 300B tube, this cost-no-object hybrid high-end preamplifier was designed to work seamlessly with ubiqaudiolab power amplifiers.
After years of trying different approaches, we finally settled on the ultra-minimalist hybrid preamp design with the legendary Western Electric 300B tube. To complement the exceptional micro/macro dynamics, exemplary transparency, and resolution of our power amp, we needed one thing: seamless reproduction of true human character throughout the music reproduction, and that was only possible by using a direct-heated triode of the caliber of the 300B.
This tube, introduced by Western Electric in 1938 and recently reissued by the same company, met all our requirements in terms of dynamic expressiveness, inner resolution, unforced transparency, and natural harmonic spectrum, which finally combined all the elements found in real musical performances that are necessary for a system designed to give the impression of reflecting a live musical event. No other tube type and no other 300B manufacturer was able to deliver this.
Neutral and accurate sound is one thing, but to get anywhere near realistic and life-like reproduction levels requires much more effort. We believe that we have fully accomplished our task.
Features
- dual-mono class-A topology design with five ballanced inputs and three ballanced outputs
- two variable and one fixed volume level ballanced outputs, each with its own buffer stage
- fully symmetrical ballanced J-FET class-A input stage
- legendary Western Electric 300B tube with its unique harmonic signature, implemented in intermediate single-ended class-A gain stage
- 300B tube mechanical dampeners to minimize acoustical feedback
- state of the art volume level control by legendary ALPS RK501 potentiometer
- 333 steps from min. to max. direct-drive volume level control by precision stepper motor
- IR remote and manually switched input select, output mute, phase invert and gain levels
- easy to follow back plate indication of input select, phase invert and mute functions
- very large energy storage, high quality Mundorf electrolytic capacitor bank
- V-Cap Odam high quality coupling and decoupling capacitors
- Jupiter copper and silver foil paper-wax coupling and decoupling capacitors for greater audio resolution
- separate switch mode power supply for each channel with solid-state soft start circuitry
- common-mode/differential power supply EMI filters
- non-intrusive, multi functional MCU controlled protection circuitry (output DC-error, temp)
- high quality printed circuit boards with 130 um ultra thick copper layers
- convenient AC mains input phase polarity check
- double trigger-out wired connections
- chassis to earth connection binding-post
- illuminated on-time counter clock
- Furutech 16A high grade AC inlet
- custom designed decoupled feet
- custom IR remote control with wireless charger
Specifications
- voltage gain: +6 dB
- differential input impedance: 200 kOhm
- signal to noise ratio with terminated inputs: – 90dB
- small signal bandwidth: 10 Hz to 1 MHz (-3 dB)
- total harmonic distortion: 0,1 % at 10 Vrms output
- output impedance: 44 Ohm
- dimensions: 480 x 130 x 490 mm (W x H x D)
- weight: 27 kg (net)
