Abbingdon Music Research LS-77 Speaker System User Manual


 
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With the most important of the rough adjustment being the front-to-back distance, mark the speakers' positions
on the floor where the front edge of the speaker would be with tape, so you can always return to this position.
The tape should extend beyond the ends of the baffle, because you will be moving the speaker relative to the
main rough position. Using a solo piano recording, move the speaker with relation to side wall in small increments,
while you listen for the 'attack', the dynamic or transient accuracy and how it affects overall harmonic integrity.
Now you can fine-tune the toe-in to have the image "snap" into focus, taking care not to alter the front-to-back
or side-to-side relationships. The AMR Test CD contains in phase and out of phase mono pink noise tracks that
can be used to optimise both the Focus (precisely defined instrument images) and depth of the soundscape. Toe-
in adjustments means only the rotating of the speaker on its centered position. Change the toe-in until the image
"focuses" right in front of the speakers with a good sense of "depth" remaining. You should cross-check using an
orchestral stereo-recording (preferably with minimal miking and not multi-tracked).
Make absolutely sure that the positioning of the speakers is truly symmetric and the degree of toe-in is identical.
Now mark the positions again on the tape, refit the spikes or other feet to the stands and return the speakers and
stands to the exact locations indicated by the tape. If you feel the bass is still too heavy or slow, after full AASR
optimisation, please experiment with adjusting the bass output using the supplied port inserts.