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1. DESCRIPTION OF THE JUBILEE 300 B
Octave has always been at the forefront of the development of powerful, sonically neutral, ultra-
stable and extremely reliable push-pull tube power amplifiers that can drive virtually any speaker on
the market. Our innovative design is now widely recognized: Thousands of satisfied listeners
appreciate the refined sonic qualities and extreme practicality of their Octave amplifiers.
What if Octave’s tube amplifier know-how was utilized in the development of a 300 B single-ended
triode output stage? A concept that is said to have legendary sonic qualities. We have often been
asked why we haven’t developed a 300 B single ended power amp, even though this amplifier
concept can offer outstanding performance.
The challenge for us was to combine our ideas regarding sound, dynamics, bandwidth and load
stability with the tonal characteristics of single-ended triode power amps, which inherently lack
performance in some regards and whose design concepts have limitations in key areas.
Our objective was to develop a 300 B amplifier that provides enough power for most speakers, while
not interfering with the classic 300 B circuit. It was not about power for the sake of power, but about
providing the 300 B with a perfect environment that enhances the tonal qualities of this tube.
The concept of a 300 B single-ended amplifier delivering 20-30 W output power with three power
tubes in indirect parallel operation was thus born.
There is a fundamental problem regarding "direct" heating of the triodes:
Unlike indirectly heated tubes (such as the KT88, KT120, etc.), directly heated triodes cannot operate
directly in parallel because of the complex demands on the heating system needed increase output
power. The typical 50 Hz AC-heater voltage would cause unacceptably high hum and power
disturbances in the speaker. Although DC-heating eliminates the hum, it also limits the sonic potential
of the 300 B.
Octave’s solution:
We have developed a 7 Hz power generator that supplies each of the three 300 B tubes with a
separate, regulated 7 Hz pure sine wave heating voltage.
- This makes it possible to connect several 300 B tubes in parallel.
- Sound-affecting ripple and RF disturbances of the line frequency are completely eliminated.
- Heating and operating voltage are electronically controlled, sound instabilities due
the fluctuating mains voltage is a thing of the past.
Only then can the tonal potential of the 300 B be fully exploited.
The 300 B tubes will now operate in the optimized region and can fully develop their tonal qualities.
Now it becomes clear why she is called the "queen" of tubes.
Thus, the Octave JUBILEE 300 B is an absolutely modern and uncompromising implementation of
arguably the finest amplification technology in the high-end sector. The amp offers an emotional,
smooth, high-resolution, dynamic and expansive triode sound, not only in the mid/high frequency
range, but for the first time, completely across the full audio band.
JUBILEE 300 B, a new generation of single ended amplifier technology without limitations.
