1.) place our beauty, lying on the back on a cover or your bed. (it
begins very hot). You might want to roll up the tailpiece in a rag to
avoid any damage to the top; in fact only if one must remove all the
strings (in order to work on the tailgut, the tailpiece, or the bridge
for example)
2.) mark the placement of the bridge on the top with a soft lead
pencil (taking care not to damage the varnish) because the tension of
the new strings will tend to pull it upwards; it will then be easier to
move the bridge to its initial place.
3.) change the strings one by one to maintain the soundpost
(French translation: l’âme = “the soul” : it is the romantic moment) in
its place, by keeping some pressure on the top. The order of the change
is of no importance, just avoid to overlap the strings in the pegbox.
We can start with the G string, even if it means to loosen the D if
there are some difficulties when the G passes under the D in the pegbox
(it is the case on my double bass), then comes the D then A and finally
E even B (we are far from the erotism of the beginning although...)
So remove the G string ; a small paper clip can make the task a
little easier. Then take the end of the new string through the hole of
the peg, which has been oriented towards the floor and the scroll. Take
the end of the string and get out from there 1/4 to 1/3 of the silk end
(i.e. the part that is spun with soft coloured silk) out of this hole.
The free end of the string is brought under the vibrating part of the
string ; thus the string will be blocked on the peg (David Gage suggest to twist
the string against itself).
(the arrow shows the direction of the rotation of the peg in the pegbox)
Now just turn the tuner handle to roll up the string around the
peg. I maintain tension on the string and I point the string towards
the inside (compared to the hole of the peg in the pegbox), then
towards the outside (by crossing the turns of the string), so that at
the last turn the string arrives towards the notch in the nut. (there
really the language with words is confused, look rather at the diagram)
note on the diagram and the photograph : there’s no rotation of the
string towards the inside (compared with the hole of the peg) only
towards the outside because the thickness and the length of the string
don’t make it necessary.
4) coat each nut slot and bridge slot with a good layer of pencil
quite fatty 6B or more, for each string. That will allow the strings to
move freely at the time of tensioning and at the time of tuning. (less
abrasion of the string and less movement of the bridge) The loose
extremity could be possibly trimmed if you don't plan on using the
strings on another double bass. We can also roll the ends in elegant
loops, by paying attention so that it cannot create unwanted noise by
their vibration on another string or on the pegbox.
5.) maintain the bridge at right angle compared to the top, with
pulling the bridge with the whole hand at the time of tensioning the
strings, so that the top of the bridge does not get pulled towards the
nut.
Important rules:
For the placement of the bridge : the center of the foot of the
bridge must stand on an imaginary line between the notches of the
f-holes. The bridge must be vertical ; the lower face of the bridge
(towards the tailpiece) must be at a 90° angle to the top.
For the placement of the strings : the E and G strings must be at equal distances of the edge of the fingerboard.
On the bridge the depth of the notches should be at a maximum of
1/3 of the diameter of the string (to allow the string to vibrate
freely) On the level of the notches of the nut: their width should be
just larger than the diameter of the string (to avoid damaging the
string)