Damper harmonics

[Newton Hunt]

Take two pieces of trichord felt of the standard length.
Remove the offending damper.
Place the two felts in standard locations.
Move pieces back and forth until the offending partial is muted.
Note location and glue them on the head to conform.

Because of the height of the plate strut you can glue on dampers that will go
under that brace so you can have longer felts than the block is long.

Yesterday I tuned three Ds and checked each on for that partial by playing with
the head.  I was unable to elicit that partial.  You may have a damper piece
located just enough off to hit that node.

I once had a Knabe in the shop with this type of problem throughout the bass.
I used this technique to discover that the damper heads were too short.  By
extending the damper felt beyond the heads by 1/8" each end I was able to get
superb muting.  The trick there was to get them located well enough to look
neat.

      Newton
      nhunt@rci.rutgers.edu