Abbingdon Music Research LS-77 owner manual

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Why do we have reverberation? The speed of the propagating sound wave is very slow - at least compared to light: approx. 1130ft. or 340m per sec.

If there are no reflecting surfaces between the sound source and our ears, only the direct sound is heard and there is no reverberation. If there is a single reflecting surface we may hear the reflected sound in one way or another, but there is still no reverberation. If the sound is generated in a room, there are a whole lot of reflections. Each of these travels different paths with different distances on the way to the receiver. Each time the sound hits a surface it may loose some energy if the surface is absorbing.

One sound source and one listener in an open area. Only sound coming direct from the source is heard.

One sound source and listener in a room. The sound impulse is reflected via many surfaces. All the reflections are melting together and heard as additional reverberation.

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Contents LS-77 Reference Class Professional Monitor Loudspeakers Page Page Precautions Running-InContents Page Unpacking Front Panel of the LS-77Please check that all contents are present Component Overview LS-77 Front FasciaContact with the chassis Setup Connecting the loudspeakersUsing AMRs OptiLink Speakon Cable Speaker R Speaker L Using Binding Posts Speaker Cable Stereo Amplifier Interconnect Cable Connecting the amplifier Multi-channel set upChoice of loudspeaker cable Positioning Symmetry and room modesDistance between the loudspeakers Distance to the loudspeakers Distance to back and side wallsLevelling/Speaker Support Loudspeaker Toe-in Room and furniture influenceCare and maintenance Care & MaintainanceRunning-in the loudspeakers Power rating LS- 77 Technical Features Troubleshooting Troubleshooting GuideSpecifications Specifications TableAppendix a Adjustment of tonal balan ce HF Level Placement Suggestions HF Level R1 Placement Appendix B Abbingdon Acoustic Setup Regime Page ~100″/254cm ~115 ″/290cm Page Page Appendix C Biamplifying the LS-77 LS-77 Speaker R Speaker L Speaker Cable Appendix D The AMR Active System AM-77 Control Center Edition CCESetting up the AMR Active System Line Level ConnectionSpeaker Connection Scenario Testing and Troubleshooting the AMR Active System AMR Active System Configuration Diagram LS-77 Speaker LAppendix E LS-77 in OptiArray configurations Introducing AMRs OptiArray scalable acoustic systemPage AMR recommends the following OptiArray Setups Epsilon/Zeta Iota/Zappa Omicron/Sigma Epsilon/Zeta System wiring Appendix G Acoustics Background In formation AcousticsGood acoustics Reverberation timePage Diffusers Absorption or Diffusion ?Absorbers Membrane absorbersStanding Waves Porous absorbersRoom modes