Octave · Power Amplifiers
Jubilee 300 B
The Jubilee 300 B is a single-ended monoblock running three 300B triodes per channel in parallel, delivering 15 to 30W depending on the power setting.
fig. 01 · power amplifiers
Jubilee 300 B
current
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From Octave
Three 300B tubes run in parallel per monoblock, a configuration that directly heated triodes normally can't sustain because of AC heater hum. Octave's solution is a purpose-built 7Hz power generator that supplies each of the three tubes with its own regulated, pure sine wave heating voltage, removing line-frequency ripple and RF interference from the signal path.
Output power is selectable between 15W and 30W across a 3-stage Low, Med, and High power preselection, which adapts the amplifier to alternative 300B tube types. Frequency response runs 20Hz to 50kHz at full power, with a separate BIAS display for monitoring each 300B tube.
A single RCA input and single XLR input feed the amplifier, with speaker outputs for both 4 and 8 ohm loads. An optional bi-amping package, not field-retrofittable, adds a level control, switchable gain, and a 100Hz low-cut filter for pairing the Jubilee 300 B with a separate bass amplifier.
Specifications
| Basic model | Jubilee 300 B |
|---|---|
| Options | Remote switching, bi-amping package |
| Design | Silver or Black, middle section optionally available in various precious wood veneers |
| Tube configuration | 3 x 300 B |
| Inputs | 1 x RCA, 1 x XLR |
| Dimensions | 240 x 660 x 400 mm (W x H x D) |
| Weight | 55.0 kg |
| Outputs | 4 and 8 ohms speaker outputs |
| Eco Mode | Power saving mode |
| Power preselection | 3-stage current adjustment, Low, Med, High - allows adaptation to alternative 300 B tubes |
| Bias Control | separate BIAS display for 300 B |
| Protection System | Inrush current delay (soft start); Protection circuit for device and output tubes |
| Heating system | linear 7 Hz generator |
| Output power | Selectable between 15 and 30 W |
| Frequency range | 20 Hz - 50 kHz / -3 dB at full power |
| Signal-to-noise Ratio | Gain High > 100 dB; Gain Low > 110 dB |
| Gain | Gain High: 30 dB; Gain Low: 19.5 dB |
| Input sensitivity | Gain High: 0.5 V; Gain Low: 1.7 V |