Features

• Regulated electronic power supply instead of a choke power supply
• Power generator for triple 7 Hz heating voltage with pure sine wave
• Energy management for supply and heating voltage to extend the lifetime of tube and amplifier
• Protection and overload system to protect the tubes and the amplifier against tube damage and operating errors
• Adjustable BIAS levels to allow the use of different 300 B-tubes: low, medium and high (equivalent to 25mA, 50mA and 70mA quiescent current per 300B)
• BIAS meter for controlling the three output tubes
• Speaker output terminals for 4 and 8 ohm speakers
• Trigger/remote switching is optional
   

Our objective was to develop a 300B amplifier that provides enough power for most speakers, while not interfering with the classic 300B circuit. It was not about power for the sake of power, but about providing the 300B with a perfect environment that enhances the tonal qualities of this tube.

The concept of a 300B single-ended amplifier delivering 20-30W 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 300B.

Octave's solution:

We have developed a 7 Hz power generator that supplies each of the three 300B tubes with a separate, regulated 7 Hz pure sine wave heating voltage.

• This makes it possible to connect several 300B 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 300B be fully exploited. The 300B 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, highresolution, 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. 

Options:

An exciting option for the Jubilee 300 B, the bi-amping package dramatically expands the application possibilities of these brilliant mono amplifiers, as even 30 pure Class A watt amplifiers will have limits.

If you wish to enjoy the seductive sound of triodes in very large rooms or with power-hungry speakers, it is often beneficial to control the bass region by utilizing a separate power amplifier for the low frequencies. However, such traditional bi-amping requires a level of customization, thus this optional package (which is not retrofit upgradeable) includes several important features to optimally integrate the Jubilee 300B with the bass amplifier.

• The most important tool is a level adjustment to optimize the sensitivity of the Jubilee 300 B to the bass amplifier. With this controller you can perfectly integrate any amplifier into the system.

• Switchable Gain: one low and one high.

This enables one to match the amplification factor of the Jubilee 300 B amplifier to the efficiency of different loudspeakers (for speaker models over 88 dB sensitivity – gain Low, or in case the level of the Preamp and the DAC is very high). This allows the volume control of the preamp to be used in the optimum range while also further reducing noise. In principle, all loudspeakers with sensitivities as low as 82 dB and greater than 106 dB can thus be perfectly driven.

• A low-cut filter that relieves the Jubilee 300 B of frequencies below 100 Hz. Of course, all functions are switchable. 
Another option for the Jubilee 300 B (also not retrofittable) is the remote function - A classic trigger that switches on the power amplifiers (with the pre-amp turned on).