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RE 290

Summary of Contents for RE290

Page 1: ...RE 290 ...

Page 2: ...insights into the interaction of amplifier and loudspeaker With tube amplifiers in particular a general reluctance to depart from the classic circuit designs has not done the technology any favors Although today s loudspeakers and source equipment provide better performance than ever before they also present greater demands on amplifiers Modern sound reproduction equipment delivers a level of perf...

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Page 4: ... controls 13 5 Rear panel connections 14 6 Advanced functions 16 6 1 Power selector alternative power tubes 16 6 2 Electronic Protection System 17 6 3 Soft Start Inrush current limitation 17 6 4 Ecomode power saving mode 18 7 Tubes 19 7 1 Removing the grille 19 7 2 Tube layout 19 7 3 BIAS measurement facility 20 7 4 Replacing the tubes 23 7 5 Running in the tubes 23 7 6 Tube service life 23 8 Usin...

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Page 6: ...ion of the load thus improving dynamic range separation depth soundstage size and articulation This enables optimizing the RE 290 in respect to the speaker which is a tremendous benefit if the speaker is difficult to drive Input Section Unlike other designs the RE 290 offers single ended RCA and true balanced XLR inputs with a very high common mode rejection ratio that eliminates unwanted hum and ...

Page 7: ...engineer to replace blown fuses with ones of the same type and rating If your amplifier requires servicing please ship or take your equipment directly to OCTAVE or to one of our authorized service centers Modifications to OCTAVE equipment Use audio grade fuses and other power cables at your own risk The use of such devices will void the warranty This also applies to the use contact fluids on the t...

Page 8: ...ble materials gases or vapors Avoid areas where there may be heavy accumulations of dust or where the unit may be subject to mechanical vibration Place your OCTAVE amplifier on a stable level surface 2 Grille Never operate the amplifier without the protective grille in place 3 Ventilation Make sure that your amplifier has an adequate flow of air around it If you intend to install your equipment in...

Page 9: ... layout diagram Power cord 4 0 x 100 flat bladed screwdriver for adjusting the bias Owner s manual with warranty card 3 2 Removing the grille Operating the amplifier without its protective grille is dangerous and not recommended To remove the grille 1 For your own safety switch the amplifier off using the on off switch or disconnect the power cord 2 Pull the grille upward to remove ...

Page 10: ...ime the Soft Start feature The RE 290 is equipped with a multi stage Soft Start Turn On protection circuit which extends component as well as tube life considerably by protecting against stress caused by typical high inrush currents during switch on 1 Check that the Ecomode switch on the rear panel is in the Eco off position 2 Connect the RE 290 to the mains On new units this switch is set to off ...

Page 11: ... Yellow LED BIAS setting of the selected output tube is too low Green OK LED BIAS setting of the selected output tube is correct Yellow LED BIAS setting of the selected output tube is too high Red off LED Indicates that the electronic protection has switched off the amplifier see chapter 6 2 After an additional 5 to 10 minutes the BIAS control LEDs will change from yellow to green in case the BIAS...

Page 12: ...4 The measurement facility is connected to the relevant tubes To ensure the accuracy of any adjustments make sure that the volume control of the preamp is set to 0 NOTE The RE 290 is equipped with a soft start circuit and a power up delay timer The amplifier is ready for use after a delay of approximately 2 minutes Because there are no relays in the signal path a low level slightly distorted signa...

Page 13: ...nput and Muting switch Toggles between the inputs RCA and XLR and the function Muting Switch up RCA input is active Switch central XLR input is active Switch down both inputs are muted This position is useful for connecting and disconnecting cables without switching off the amplifier XLR Input Pin 1 Ground Pin 2 Pin 3 Loudspeaker Terminal Right Channel Binding posts to connect the speaker cable Re...

Page 14: ...ding posts to connect the speaker cable Red positive terminal Black negative terminal You can connect either 4 mm Banana connectors or spades The negative speaker terminal is connected to ground Model identification plate Model and Serial Number Mains supply socket IEC socket with integrated fuse holder The fuse is located in a pullout compartment above the socket You can open the fuse compartment...

Page 15: ...ximum output power is limited to 2 x 70 W to avoid overloading these tubes The rather rare tubes of type KT 90 and KT 100 can be used also in the LOW position The EL 34 can be used in the LOW Position in cases of speakers with an impedance higher than 4 ohms Tubes of Type 6L6 KT 66 5881 EL 519 and EL 156 are not suitable for the RE 290 Before switching the Power Selector turn OFF the mains push bu...

Page 16: ...one or more of the output tubes A fault in one of the preamp tubes which overloads the affected channel Once the protection system has cut in the only way you can turn the RE 290 back on is to turn the on off switch off and then on again Allow the unit two minutes to cool down before switching it back on If possible identify and eliminate the cause of the problem see chapter 9 Troubleshooting If i...

Page 17: ...e than 10 minutes Ecomode reduces the overall power consumption of the amplifier to under 20W compared with 180W in normal operation When detecting a signal the RE 290 reactivates automatically and is ready for use again within 30 seconds Eco off The Ecomode function is off the Ecomode LED doesn t burn Eco on The Ecomode function is activated The Ecomode LED lights up in GREEN After a 10 minute si...

Page 18: ...ier off using the on off switch or disconnect the power cord 2 Pull the grille upward to remove See chapter 3 2 7 2 Tube layout V1 V2 V3 V4 V7 V6 V5 Output tubes V1 V4 KT 120 TS standard V1 V2 left channel V3 V4 right channel Driver tubes V5 V6 V7 ECC802 ECC 82 12 AU 7 5814 6189 In position 5 and 7 the use of the 12 BH 7 is allowed V 6 should have a system Gain match close to 0 2dB ...

Page 19: ...you the user to carry out the adjustment yourself without the need for test equipment The use of precision op amps makes it possible for you to set the BIAS to accuracy within 0 2 making it superior to any other method Using selected output tubes only makes sense if the idle current is adjusted accurately as is clearly shown in Fig 1 Technical Data The LED display Ecomode LED indicates the status ...

Page 20: ...lay illuminates If the yellow LED illuminates the bias is set too high Turn the trim pot counter clockwise until the OK LED illuminates If the yellow LED illuminates the bias is set too low Turn the trimmer clockwise until the OK LED illuminates Repeat this procedure with the other three tubes 4 Switch the bias selector back to its off position If there is no change in the BIAS of a tube while tur...

Page 21: ...es can be used with the KT 120 in both positions of the power selector Exception The BIAS high setting can also be used with the KT 88 in the power LOW position Certain loudspeakers may benefit from the higher BIAS current as it will increase the damping factor and provide slightly better control of the speakers LED graphs The BIAS LOW setting corresponds to the plate current of 33mA The BIAS HIGH...

Page 22: ...ubes should be allowed a longer warm up period You should adjust these tubes after about 20 minutes and control the setting in the first days of operation 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...

Page 23: ... and articulation rendering the musical reproduction clearer throughout the entire frequency range The amplifier remains unaffected by mains variations and interferences due to the noise filtering characteristics of the capacitors 8 1 The Black Box option Black Box Indicator LED High current plug The LED illuminates continuously when the power amplifier is on The LED goes out when the protection c...

Page 24: ...s powered down through the Ecomode The Super Black Box is equipped with a rapid discharge circuit which discharges the unit s electrolytics The yellow LED indicates that that this procedure is taking place The discharge circuit also activates if the SBB connecting cable is accidentally removed This is to prevent the SBB maintaining its charge when it has not been properly disconnected Specificatio...

Page 25: ...here are 3 different symptoms indicating a faulty output tube 1 Broken heater filament the tube stops glowing 2 Defective cathode layer the tube glows but no current can flow You can confirm this fault using the bias display LEDs no amount of adjustment will be able to extinguish the minus LED 3 Internal short circuit Normally the electronic protection cuts in and the red off LED illuminates or th...

Page 26: ... CMRR of the XLR Input 85dB 1 kHz Minimal Load Impedance 2 Gain 28dB RCA Eco Mode Trigger Level 0 5mV In and Outputs Inputs 1 x RCA 1 x XLR Outputs 1 x speaker terminal suitable for 4 mm Banana connectors and spades Construction double sided PCBs with plated through holes using 130µm copper ceramic tube bases with silver contacts specially selected and burned in long life tubes professional low in...

Page 27: ... 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 ...

Page 28: ...on high and 70 W in position Low is constant in the range from 25 Hz up to 30 kHz Graph 3 Noise spectrum 180 20 160 140 120 100 80 60 40 20 0 d B 30 20k 50 100 200 500 1k 2k 5k 10k Hz Noise spectrum at 1 kHz 5 W into 4 ohms there is no mains interference to be seen 50 Hz 200 µV 100 Hz 70 µV The k2 k3 k4 and k5 noise spectrum is extremely low and falls quickly ...

Page 29: ... of course be reduced The amplifier will come to no harm if it is operated continuously like this Operation without driver tubes is also possible for test purposes although for obvious reasons music playback is not possible 5 What is the significance of loudspeaker impedance and efficiency The impedance and efficiency of modern loudspeakers is not an issue for OCTAVE amplifiers The often quoted da...

Page 30: ...e de 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 ...

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