10 years ago. These advances have been achieved through the application of the latest technological developments as they become available and affordable. OCTAVE has specialized in tube amplification for the past 25 years, during which time we have developed a number of innovative technologies that have earned us a reputation as one of the leaders in the field.
CONTENTS Page Introduction ....................Description of the RE 290 ................Safety instructions ..................Before you begin ..................Placement ....................Warranty ....................... Getting started ....................Unpacking, package contents ..............Removing the grille ..................Installing the power tubes ................Switching on for the first time: the soft-start feature ........Checking the tubes (BIAS) ................
1. DESCRIPTION OF THE RE 290 The new Octave RE 290 stereo power amplifier is a push-pull pentode design delivering 2 x 100 W RMS output power (into 4 ohms loads). As with all Octave models, all research and development (R&D) and production has been conducted exclusively in-house, and the amplifier is...
Servicing and maintenance For reasons of safety, please ensure that any servicing, repairs or other modifications to OCTAVE equipment are carried out only by a qualified technician. Always get an engineer to replace blown fuses with ones of the same type and rating.
2.2. Placement 1. Location OCTAVE equipment is designed strictly for use in a dry domestic environment. Do not use it in the open air or in damp environments! Never place plants or liquid-filled containers on your OCTAVE equipment. Take care to avoid dropping objects or spilling liquids into the case.
3. GETTING STARTED 3.1. Unpack and check the contents of the box. Package contents standard RE 290 serial equipped with 5 x KT120 power tubes 5 power tubes packed separately with tube layout diagram Power cord 4.0 x 100 flat-bladed screwdriver for adjusting the bias Owner's manual with warranty card 3.2.
3. GETTING STARTED 3.3. Installing the power tubes The power tubes are packed in a separate box in the tube compartment Insert the power tubes into their sockets as shown on the tube layout. Ensure that you correctly locate the anti-rotation lug on each of the tubes. Anti-rotation recess on the tube socket 3.4.
Connect the other components in your system to the appropriate sockets on the rear of the RE290. (See chapter 5 "Rear panel connections". Check that the switch positions on the front and rear of the amplifier are in their recommended settings.
4. FRONT PANEL CONTROLS Mains Power push button switch To switch on the amplifier, push the knob. The LED next to the knob lights up gradually. Important! : Do not pull on the knob when it has been pushed in, as this could damage the retaining mechanism.
5. REAR PANEL CONNECTIONS RCA Inputs RCA cinch input Input for preamplifier (using RCA cinch interconnect) Ecomode Switch Eco off: Ecomode automatic is off. Eco on: Ecomode automatic is on. During Ecomode ON the Ecomode LED lights up in green.
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5. REAR PANEL CONNECTIONS Black-Box-Connector The (Super) Black Box is an outboard power supply capacitance upgrade for the power amplifier section (see chapter 8). You should switch off the RE 290 using the power switch before connecting and disconnecting the Black Box! ...
6. ADVANCED FUNCTIONS 6.1. Power Selector, alternative output tubes Position „HIGH“: KT120 Position „LOW“: KT88, 6550, KT90, KT100 (EL34 with Restrictions) The Power Selector allows adjusting the RE 290 in accordance to the output tubes. Position HIGH is reserved for the standard KT 120 tubes. In the HIGH Position the RE 290 is able to deliver 2 x 100 W RMS Output Power.
6. ADVANCED FUNCTIONS 6.2. Electronic Protection System The RE 290 features a comprehensive electronic monitoring and protection system. This system will automatically switch off the RE 290 in case of a fault occurring in the power section. The protection system has been designed to keep the unit safe from the consequences of overloads of any kind and to protect the output tubes from current surges.
Ecomode is indicated by the Soft-Start-LED. The signal switching level of 0.5mV results in approx. 40µW output power of the RE290. In case of a speaker with a high efficiency an adjusted listening level can be lower than this value.
7. TUBES 7.1. Removing the grille Operating the amplifier without its protective grille is dangerous and not recommended. To remove the grille: For your own safety, switch the amplifier off using the on/off switch or disconnect the power cord. Pull the grille upward to remove. See chapter 3.2.
7. TUBES 7.3. BIAS measurement facility The BIAS measurement facility makes it easy for you to check and adjust the idle current of the output tubes. Getting the BIAS setting right for all four tubes is critical for both the sound of the power amplifier section and for the service life of the tubes.
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7. TUBES How to set the BIAS Make sure that no signal is playing through the amplifier when you are adjusting the BIAS. It is sufficient to turn your preamp volume control to 0; there is no need to disconnect the speakers. The tubes should have reached operating temperature.
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7. TUBES LED graphs, advanced adjustments of the BIAS setting There is an upper adjustment limit to the "high" BIAS setting, which is indicated by the green and red LEDs lighting up at the same time, and a lower limit to the "low setting, where the yellow and green LEDs light up.
7.5. Running in All OCTAVE equipment is subject to a 48-hour performance test at the factory to break in the tubes. The tubes are preselected for use in each particular model. New tubes can take up to three months to run in and start sounding their best.
OCTAVE, with the Black Box technology, offers an instrument for optimizing the OCTAVE amplifier in respect to the speaker. This flexibility is a unique feature of the OCTAVE brand. The dynamic and tonal stability of an amplifier is strongly dependent upon the stability and capacity of the power supply, therefore the Black Box and Super Black Box were developed as external upgrades to the OCTAVE amplifiers’...
8. USING THE (SUPER) BLACK BOX 8.2. Super Black Box option Operation Blue power LED The blue "power" LED illuminates when the power amplifier is switched on via the amplifier's power on/off switch. Yellow unload LED The yellow "unload" LED (discharge control circuit) lights up for approximately two seconds after switch-off, in case the electronic protection is activated and if the RE 290 is powered down through the Ecomode.
9. TROUBLESHOOTING H um in the speakers Possible cause: multiple grounds Hum in an audio system is often caused by several system components having their own separate grounds. It is particularly common in systems containing tuners, VCRs or satellite receivers, as these components are connected to an aerial.
10. SPECIFICATIONS AND DIMENSIONS Power Amplifier. Configuration: push pull pentode circuit, class A/B; negative grid voltage adjustable separate for each power tube through ten turn precision regulators. Special wideband output transformers using high efficient PMZ core. Output Power into 4 ohms: Power Selector High: 2 x 100 W RMS Power Selector Low:...
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12. SPECIFICATIONS AND DIMENSIONS Dimensions: Diagrams THD at 4V into 4 ohms from 30 Hz to 20 kHz at a variety of BIAS settings Diagramm 1 Curve 1: BIAS adjusted correctly Curve 2: BIAS 10% out Curve 3: BIAS 30% out...
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12. SPECIFICATIONS AND DIMENSIONS Graph 2: Power Bandwidth Power bandwidth of both positions of the power selector. The maximum output power of 100 W in position “high” and 70 W in position “Low” is constant in the range from 25 Hz up to 30 kHz. Graph 3: Noise spectrum -100 -120...
Can you operate the RE 290 when no loudspeakers are connected? Yes. The RE290, like all OCTAVE amplifiers, is fully protected against open circuit operation, i.e. the amplifier will come to no harm if it is operated without loudspeakers connected.
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We reserve the right to alter and improve the specifications in pursuit of better. OCTAVE logo is a registered trade mark of Andreas Hofmann. Copyright by Andreas Hofmann. Reproduction in whole or part is prohibited. edited EN2011 OCTAVE AUDIO Germany...
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