News
Technical Analysis of a Baroque Recorder

We recently had
the opportunity to run a technical analysis of the Bressan Treble
recorder. The University of Southampton
has installed an industrial CAT Scanner and we were given the chance to put the
instrument through for 3 dimensional scanning.
The instrument was
placed in a padded plastic tube, which in turn was clamped into the scanner. There is a necessary compromise regarding levels and timings as the most
accurate scan would take longer to complete than a less accurate one, the time
scales being matters of several hours.
However, as we are talking about accuracy to 1/100’s of microns, it was felt, for the preliminary scan, that
we didn’t need measurement to that level and finally decided that we could run
a 4 hour scan to an accuracy of 60 microns.
This would still give us a very clear image and be more
accurate than any of our previous measurements by a very high degree. The scan
comprises rotating the instrument through 360 degrees while X-Ray section
images are taken. A computer programme
then combines all scans to produce a 3 dimensional image, which can be examined
through all sections. Many people will be familiar with this concept as it has featured on a number of popular TV
archaeology shows. The finished image on the computer screen was very fine indeed and we were able to see
through sections of the instrument and examine splits, cracks and dimensions to
an incredibly accurate level. The scan also provides all necessary data to reproduce the images on another computer with the appropriate software. It is
immediately apparent that this technology has a number of applications for
historical musical instruments. From a
conservation point of view it is now possible to examine the condition of an
instrument and determine to what extent it might be playable. Additionally, if a series of scans are taken
we can make accurate measurements of the extent that instruments deteriorate over time. From a technical-measurement point of view, this can give us very fine measurements of the components of the
instrument, not only from the exterior, but also interior features. For the first time it will be possible to
make an accurate examination of the recorder block without going through the
potentially destructive process of removing it.
In addition it is possible to see the details on tone-hole undercutting. In fact, I was led to believe that the finished data can be programmed into a Computer Numerately Controlled Lathe to reproduce the instrument to a high degree of accuracy. We still need
more time with this technology before we can establish a protocol for how we
use it. In its current form it is very
time-consuming and expensive and would require a special research programme to
optimize its use.