Every bassoonist has a set of basic measurements they use for their reeds.  Below are the measurements I use, barring in mind that these are guidelines.  Just because you make a reed exactly to these measurements does not mean it will play, that would be too easy!  The type of cane, density of the cane, age of the cane, weather, and a million other things factor into how a reed will perform and what the final measurements for each reed will need to be.  These measurements are to give you an idea of where a reed usually falls, but then you have to pay attention to the cane and reed to see how far outside the parameters each individual reed needs to be to play best.

Because I’ve studied in both metric and imperial countries, I actually mix and match my measurements.  Sometimes I use metric and sometimes I use inches.  I’ve put conversions for both in the table.  The measurements that I use are starred * so you know when I’m thinking in which measurement.

Basic reed structure lengths:

Reed Part Metric
USA
Tube 27 – 30mm* 1 1/16 – 1 2/16 inch
Distance between 1st and 2nd wires 7.5mm 5/16 inch*
Blade 30mm* 1 2/16 – 1 3/16 inch

When measuring the blade thickness, you will need to use a dial indicator.  My dial indicator is in inches, so those are the measurements I use.   (But my dial indicator is set up to read thousandths of an inch so where my table below says 0.0314, my dial indicator actually reads 31.4.  Make sure you understand what your dial indicator is measuring and how it compares to the table below before taking off cane!)  I start measuring at the collar, then each measurement is forward by 3 mm down the center of the reed.

Note that there are three different thickness for the first measurement, right after the collar.  The measurements differ depending on the basic needs for the reed.  A thicker back to the reed means the reed will be harder and high notes should be easier, but low notes and soft dynamics will be more difficult.

Basic blade thickness guide:

Metric (mm) USA (inch)
Back of blade for high note reed 1.2 0.047
Back of blade for normal playing * 0.8 – 1 0.0314 – 0.039
Back of blade for continuo playing 0.08 0.03
Forward 3mm from back of blade 0.76 0.029
Forward 6mm from back of blade 0.72 0.0283
Forward 9mm from back of blade 0.68 0.0267
Forward 12mm from back of blade 0.64 0.025
Forward 15mm from back of blade 0.58 0.0228
Forward 18mm from back of blade 0.5 0.0196
Forward 21mm from back of blade 0.4 0.0157

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