Abbingdon Music Research LS-77 owner manual

Page 31

If your floor is not carpeted (which is a bad idea acoustically) you may want to put something between the speaker stand and floor that will allow you to slide the speakers more easily, like a cloth or mat with a smooth underside. If your stands’ lower surface is not smooth and you have a carpeted floor you may wish to place the stand on a suitable piece of MDF or wood with smooth surfaces to making sliding the speakers around easier.

Position each speaker in the center of each ZOLI, pointing directly at the listening position. This may seem like an extreme amount of toe-in, but it is in most cases the best initial point. You should just be able to see either the inside walls or outside walls of the speakers.

Next, you need to 'calibrate' the floor with tape as shown in the illustration to help you shift the speaker repeatably in small increments. Using l/2" or one centimeter markings will be fine. The strips marked 0-1-0 (parallel to the back wall) should be located close enough to the speaker stands front-most corner so as to help you to gauge both left-to-right movements and to adjust the amount of toe-in or toe-out. Again, you should enlist the help of an assistant for be next phase of the AASR, as it is difficult to do it alone.

Using a full-range, well-balanced recording played at a moderate level first ensure the tonal balance of the speaker has been correctly adjusted. This is easiest judged using a recording featuring female voice and piano. Do not consider the bass output at this time, check only the midrange tonal balance for the right degree of openness and natural tone, without sounding neither dark or bright.

Next make notes regarding the sound quality as your assistant moves the speakers first forward/backward and then left/right. By using the tape rulers as accurate indication of the position you or your assistant can move the speaker as far as needed to find the point where further movement into this particular direction does not bring further improvements and still return to the best position. Listen for the best tonal balance and the ability of the system to portray dynamics as well as the beginnings of good imaging. Conventional wisdom applies here: if the system sounds bass shy, move the speakers back, bass heavy, move them forward.

31

Page 30 Page 32
Image 31
Page 30 Page 32
Contents LS-77 Reference Class Professional Monitor Loudspeakers Page Page Running-In PrecautionsContents Page Front Panel of the LS-77 UnpackingPlease check that all contents are present LS-77 Front Fascia Component OverviewContact with the chassis Connecting the loudspeakers SetupUsing AMRs OptiLink Speakon Cable Speaker R Speaker L Using Binding Posts Speaker Cable Stereo Amplifier Interconnect Cable Multi-channel set up Connecting the amplifierChoice of loudspeaker cable Symmetry and room modes PositioningDistance between the loudspeakers Distance to back and side walls Distance to the loudspeakersLevelling/Speaker Support Room and furniture influence Loudspeaker Toe-inCare & Maintainance Care and maintenanceRunning-in the loudspeakers Power rating LS- 77 Technical Features Troubleshooting Guide TroubleshootingSpecifications Table SpecificationsAppendix 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 AM-77 Control Center Edition CCE Appendix D The AMR Active SystemLine Level Connection Setting up the AMR Active SystemSpeaker Connection Scenario Testing and Troubleshooting the AMR Active System LS-77 Speaker L AMR Active System Configuration DiagramIntroducing AMRs OptiArray scalable acoustic system Appendix E LS-77 in OptiArray configurationsPage AMR recommends the following OptiArray Setups Epsilon/Zeta Iota/Zappa Omicron/Sigma Epsilon/Zeta System wiring Reverberation time Appendix G Acoustics Background In formationAcoustics Good acousticsPage Membrane absorbers DiffusersAbsorption or Diffusion ? AbsorbersPorous absorbers Standing WavesRoom modes
Top Page Image Contents