Abbingdon Music Research LS-77 Reference Class - Manual (Page 15)

15
Appendix A - Tonal Balance Adjustment
If you feel that the tonal balance in the upper midrange and lower treble frequencies of the LS-77 is not
correct for you, you may wish to change the
resistor combination fitted under the cover la-
belled “High Frequency Level Adjustment”.
Some of the required adjustment may be due
to the differences in listening distance while
others may be a result of differences in taste
and furnishings.
Remove the resistor cover using the 2mm
metric hex key (Allen Key). Under the cover
you will find two resistors one marked 15Ù and
one marked 47R in default condition.You will
also find a pair of optional resistors included
per speaker, one marked 100 and the other
marked 220.
Respectively the resistor marked 100 will be
referred to below as 10R, the 15Ù as 15R and
the one marked 220 as 22R. Using different
combinations allows an adjustment of the
upper midrange and lower treble frequencies
by +/-3dB in steps of around 1.5dB.
A.1 High Frequencies Adjustment