Abbingdon Music Research Dual Mono Pre-Main Amplifier AM-77 Owner's Manual
Summary of Dual Mono Pre-Main Amplifier AM-77
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Am-77 reference class dual-mono pre-main amplifier owner’s manual.
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3 fcc declaration of conformity - united states only this device complies with part 15 of the fcc rules. Operation is subject to the following two conditions: (1) this device may not cause harmful interference, and (2) this device must accept any interference received, including interference that ma...
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4 this products complies with the emc directive (89/336/eec) and the low voltage directive (73/23/eec) issued by the commission of the european community. Compliance with these directives implies conformity to the following european norms (in parentheses are the equivalent international standards an...
Page 5: Warnings
5 the exclamation point within an equilateral triangle is intended to alert the user to the presence of important operating and maintenance (servicing) instructions in the literature accompanying this component. This component weighs over 40 kilograms. Do not place this component on an unstable cart...
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6 care should be taken so that objects do not fall, and liquids are not spilled into the enclosure through any openings. This component should be serviced only by qualified amr service personnel when: a. The power cable or the power input socket has been damaged; b. Objects have fallen, or liquid ha...
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7 on placement with a total of 2 thermionic electron valves, the am-77 may become warm during operation. This is normal. Given this, it is imperative that the am-77 when installed, its location or position does not interfere with its proper ventilation. For example, it should not be situated on a be...
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8 horizontal position only. Do not place heavy objects on the component. Keep the component away from equipment with strong magnets, such as microwave ovens or large loudspeakers. To prevent fire or shock hazard, do not place vessels filled with liquids, such as vases, on the component. Touch-sensit...
Page 9: Contents
9 contents warnings 5 section 1 - unpacking and setup 11 1a. Unpacking 12 1b. Setup section 2 - component overview 15 2a. Start-up section 3 - advanced features 25 3a. Labeling of inputs and setting level offset 25 3b. Setting fixed input level 28 3c. Optimains® protection for excessive under/over-v...
Page 10: Specifications
10 section 4 - system configurations 33 4a. Optioperation® different system configurations 33 4b. Switching and connection diagrams for different modes 41 section 5 - additional connectivity 53 5a. Input for ipod/other portable music players 53 5b. ‘hifi/pro’ switches for balanced xlr inputs 54 5c. ...
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11 figure 1.1 - front panel of the am-77 dual mono amplifier am 77 - - section 1 - unpacking and setup figure 1.2 - rear panel of the am-77 power on off sync balanced input designed and engineered in great britain dual mono amplifier am 77 - + + _ _ 90v 135v 190v 260v ～ ac in speaker output speaker ...
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12 thank you for purchasing this amr reference class component. We hope you derive as much pleasure from using this component as we have enjoyed making it for you. 1a. Unpacking this section refers to the unpacking of the am-77 and its subsequent setup. Upon unpacking, please find: i. Am-77 referenc...
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13 1b. Setup pre-main stereo amplifier connection the following diagrams illustrate the standard connection of the am-77 in pre-main stereo amplifier mode. This is the default factory setting and is suitable for the majority of audio systems. Figure 1.3 depicts the use of standard banana/spade speak...
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14 figure 1.3 - system connection using banana plug/spade connector equipped speaker cables figure 1.4 - system connection using speakon connector equipped speaker cables i. Connect the respective spade/banana/speakon connectors of the speaker cables to the am-77. Ii. Connect the source/s via the re...
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15 figure 2.1 - am-77 front fascia f5 f4 f3 f2 f1 dual mono amplifier am 77 - - section 2 - component overview f1. Standby switch: to place the am-77 in active or standby mode. F2. Source selection buttons: to select between the 5 different inputs. F3. Volume buttons: to adjust the volume level. F4....
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16 figure 2.2 - am-77 rear panel r1. Spade/banana outputs: for connection of standard termination speaker cables. R2. Speakon outputs: for connection of speakon terminated speaker cables. R3. Hifi/pro switch: to allow for a source with transformer balanced output*. R4. Int/power amp switch: to alter...
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17 r7. Inputs 2-5: rca inputs, for signal input of source equipment. R8. Sync connectors: for connection of more than one am-77*. R9. Rs232 option connector: to facilitate future upgrades*. R10. Infra-red link: for connection of a wireline remote control. R11. Iec power connector: for the connection...
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18 figure 2.3 - rc-77 remote control remote commander rc -77 khz in vol amplifier cd processor rc4 rc3 rc1 rc6 rc2 rc5 rc7 rc1. Menu button: to enter advanced features mode*. Rc2. Standby button: to place the am-77 in active or standby mode. Rc3. Source selection buttons: to select between the 5 dif...
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19 2a. Start-up 1. Power on/off press the ‘power’ rocker switch (r12) at the rear of the amp to switch on mains power to the am-77. To switch the mains power off, press again and release. Always wait at least 30 seconds before switching on again. This is to enable the optimains® circuit to shutdown ...
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20 2. Standby after start-up, pressing the standby button (f1) on either the front fascia or the rc-77 (rc2), the am-77 will switch to standby mode. S t a n d b y 3. Source selection from either the front fascia of the am-77 (f2) or the rc-77 (rc3), select the desired source input for playback. C d ...
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21 4. Volume adjustment from either the front fascia of the am-77 (f3) or the rc-77 (rc4), select the desired volume. While adjusting volume levels, there is an audible “click” from am-77 and the speakers. This is the normal operation of the relays within the optilevel® direct path precision volume ...
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22 7. Synch connectors at the rear of the am-77 are synchronisation ‘in’ and ‘out’ connection points (r8). This is for the linking of multiple am-77s for alternative system configurations. Please refer to section 4 - system configurations for a detailed explanation. 8. Mode switch at the rear of the...
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23 12. Menu (rc-77 only) the menu button (rc1) will enter the advanced menu system of the am-77. Please refer to section 3 - advanced features for a detailed explanation. 13. Ok (rc-77 only) the ok button on (rc7) the rc-77 is for the confirmation of a desired selection within the advanced menu syst...
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25 the following section provides instructions to access the am-77’s advanced features. 3a. Labeling of inputs and setting level offset with the am-77, in one process, it is possible to label each of the 5 inputs with a corresponding source and to set the respective level offset. This function is re...
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26 list of available inputs: 1. Input x ( default) 2. Aux i 3. Aux ii 4. Aux iii 5. Cd processor 6. D/a processor 7. Dvd player 8. Dvd recorder 9. Hd recorder 10.Hdtv 11.Home theatre 12.Ipod 13.Lcd tv 14.Media center 15. Mp3 player 16. Pc audio 17. Phono stage 18. Plasma tv 19. Pre-amplifier 20. Sac...
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27 the following steps outline the procedure to label all the inputs and set the respective level offset. The am-77’s default labelling of its inputs starts from ‘input 1’ and runs through to ‘input 5’: i. Press ‘menu’ (rc1) on the rc-77. Ii. The display will flash ‘labelling input 1’. Iii. The 2 nd...
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28 3b. Setting fixed input level when using the am-77 as part of a home theatre system with an external processor controlling the overall system volume, it is possible to program one of the five input sources to have a fixed level of input such as for a home theatre system of either 0.775v (0dbu) or...
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29 - having entered the ‘fixed input’ menu, now select: fixed input 1.55v = +6dbu or fixed input 0.775v = 0dbu warning! By selecting home theater direct mode, the volume of the amplifier will be switched to full. Hence if it is used incorrectly, it will damage the connecting speakers. Amr assumes no...
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30 3c. Optimains® protection for excessive under/over-voltages the am-77 is fitted with the optimains® system to condition and adjust the incoming mains supply for best operation under all normal mains conditions (including situations that will cause audible problems without opti- mains®). In almost...
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31 3d. Optiprotect® speaker overload protection within optiprotect® the am-77 has an in-built speaker protection circuit. Unlike common protection systems which are in series with the speaker output and where the music signal always passes through the protection circuit, the amr speaker protection s...
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33 4a. Optioperation® different system configurations in keeping with amr’s philosophy that ‘no one sound fits all’ the am-77 is also adaptable to suit virtually any system configuration: able to operate at one end, as a pre-main stereo amplifier and at the other, as a single- channel power amplifie...
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34 in short, the am-77’s flexibility is limited only to that of the imagination. For example, one may employ: - 3xam-77s synchronised along with a high-quality digital crossover to drive a fully-active 3-way speaker system to the highest possible level of sound reproduction or; - 3xam-77s synchronis...
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35 figure 4.1 - mode i: pre-main stereo • standard system with am-77 as the only amplifier. L pre amp (l) 1st am -77 power amp (r) power amp (l) left speaker right speaker pre amp (r) r the following pages provide an outline of the theoretical wiring system behind each of the six different config- u...
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36 • need 2 or more am-77s. • drive low impedance speakers that only have one set of terminal connections. • ~600w/2ohm rms and ~300w/1ohm rms without current clipping. This is best suited to drive very low impedance speakers (apogee diva et al). Figure 4.2 - mode ii: pre-main monoblock l pre amp (l...
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37 figure 4.3 - mode iii: pre-main bi-amplifier • need 2 or more am-77s. • drive speakers that have more than one set of terminal connections with improved per- formance and dynamic range. • virtually all the power supply power is avail- able to the low frequency channel with imp- proved channel sep...
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38 figure 4.4 - mode iv: power stereo • same as mode i, except the pre-amplifier sec tion has been bypassed. • a separate pre-amplifier is needed to control the volume. L 1st am -77 power amp (r) power amp (l) left speaker right speaker r (l) (r).
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39 figure 4.5 - mode v: power monoblock • same as mode ii, except the pre-amplifier section has been bypassed. • a separate pre-amplifier is needed to control the volume. L 1st am-77 power amp (r) power amp (l) r 2nd am-77 power amp (r) power amp (l) left speaker right speaker (l) (l).
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40 • same as mode iii, except the pre-amplifier section has been bypassed. • a separate pre-amplifier is needed to control the volume. Figure 4.6 - mode vi: power bi-amplifier l 1st am-77 power amp (r) power amp (l) r 2nd am-77 power amp (r) power amp (l) left speaker right speaker (l) (l).
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41 4b. Switching and connection diagrams for different modes the following is a description of the switch settings and connections required to engage the various modes. Figure 4.7 - mode i: pre-main stereo amplifier (default) this is the factory default setting: the connection for which has been des...
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42 figure 4.8 - mode ii: pre-main monoblock amplifiers hifi pro mode int amp power amp l r m m analog outputs analog outputs r l usb input ir link power on off 90v 135v 190v 260v ～ ac in class 1 laser product no user serviceable components inside . , . . For service contact your authorised dealer or...
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43 note: this function requires at least 2 x am-77 synchronised pre-main amplifiers. I. Power off via the ‘power’ (r12) mains switch at the rear of both am-77s. Ii. Connect the cable from the ‘sync out’ connector (r8) of the ‘master’ amplifier to the ‘sync in’ connector (r8) of the ‘slave’ amplifier...
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44 figure 4.8 - mode iii: pre-main bi-amplifier (horizontal bi-amping) analog outputs analog outputs r l usb input ir link power on off 90v 135v 190v 260v ～ ac in class 1 laser product no user serviceable components inside . , . . For service contact your authorised dealer or distributor any modific...
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45 note: this function requires at least 2 x am-77 synchronised pre-main amplifiers. I. Power off via the ‘power’ (r12) mains switch at the rear of both am-77s. Ii. Connect the cable from the ‘sync out’ connector (r8) of the ‘master’ amplifier to the ‘sync in’ connector (r8) of the ‘slave’ amplifier...
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46 figure 4.9 - mode iv: power stereo amplifier hifi pro mode int amp power amp l r m speaker cable speaker cable interconnect cable power on off sync balanced input designed and engineered in great britain dual mono amplifier am 77 - + + _ _ 90v 135v 190v 260v ～ ac in speaker output speaker output ...
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47 i. Power off via the ‘power’ (r12) switch at the rear of the am-77. Ii. Connect the desired separate pre-amplifier to the am-77 via the balanced or rca female connector of input 1 (r6). Iii. Using a small flat blade screwdriver, move the ‘mode’ switch (r5) to the centre to select ‘l r’. Iv. Using...
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48 figure 4.9 - mode v: power monoblock amplifier hifi pro mode int amp power amp l r m m speaker cable interconnect cable power on off sync balanced input designed and engineered in great britain dual mono amplifier am 77 - + + _ _ 90v 135v 190v 260v ～ ac in speaker output speaker output l r ir lin...
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49 note: this function requires at least 2 x am-77 synchronised pre-main amplifiers. I. Power off via the ‘power’ (r12) switch at the rear of both am-77s. Ii. Using a small flat blade screwdriver, move the ‘mode’ switch (r5) to the left to select ‘m’. Iii. Using a small flat blade screwdriver, move ...
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50 figure 5.0 - mode vi: power bi-amplifier mode hifi pro mode l r m m speaker cable interconnect cable power on off sync balanced input designed and engineered in great britain dual mono amplifier am 77 - + + _ _ 90v 135v 190v 260v ～ ac in speaker output speaker output l r ir link l r 1 5 4 3 2 inp...
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51 note: this function requires at least 2 x am-77 synchronised pre-main amplifiers. I. Power off via the ‘power’ (r12) switch at the rear of both am-77s. Ii. Using a small flat blade screwdriver, move the ‘mode’ switch (r5) to the right to select ‘mm’. Iii. Using a small flat blade screwdriver, mov...
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53 5a. Input for ipod/other portable music players section 5 - additional connectivity on the front right-side panel, there is a 3.5mm jack (f4). This is for the connection of an ipod or any other portable music device for music playback through this medium. To select this source, change selection t...
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54 5b. ‘hifi/pro’ switches for balanced xlr inputs for the majority of sources, the hifi/pro switch (r3) is best left in the ‘hifi’ position. However, if the source has a pro-audio style transformer balanced output, the hifi/pro switch needs to be set to ‘pro’. A transformer balanced output uses a f...
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55 5c. Rs232 ‘options’ connector the rs232 ‘options’ connector port (r9) is for upgrading the functionality of the am-77 in future. Contact your local amr distributor/dealer for more detailed instructions. For future upgrades power on off sync balanced input designed and engineered in great britain ...
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57 the following section provides a brief explanation of the most salient technical features of the am-77. Circuit ‘x’® is amr’s unique circuit: with nos thermionic electron valves for voltage gain with a patent- pending error-cancellation circuit for the class a matched bipolar output power devices...
Page 58: Appendix - Troubleshooting
58 appendix - troubleshooting figure a.1 troubleshooting guide symptom possible cause solution with power on • poor/no power plug connection • insert the power plug firmly into the ac no power is registered at mains power point • blown fuse at mains plug • check and change mains plug fuse no sound •...
Page 59: Specifications
59 figure s.1 - specifications table inputs: 5 x rca 1 x xlr bal. Shared with 1 rca 1 x ipod® shared with 1 rca volume control: -71db – 0db in 1db steps + mute input sensitivity (ihf 2.83v out)/impedance: 20kohm power output (see notes) ihf dynamic power: 270 watts per channel at 4 or 8 ohm (stereo ...
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60 ...Continued monoblock option an unlimited number of am-77s can synchronised thermionic electron valves 5687/6900 (nos): amplification stage power transformer: 1200 va custom double c-core power consumption: standby: 50 w power on: 95 w at rated output (4r): 1000 w power supply capacitance: 96,00...
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61 notes at amr we feel that the ihf standard represents the best available rigidly mandated and standardised, musically relevant measurements applicable today (in preference to din45500 among others) despite their formidable age and our wish for something more up-to-date, while the ftc mandated sta...