Lumber drying for musical instruments

Does the speed of the drying process affect a wood's musical quality?June 21, 2000

I am in the process of manufacturing large musical drums from one piece of wood. I've begun testing kiln drying and microwave drying to speed up the curing process.

Are there differences in the final product from a speed-curing as opposed to slow-curing process, in regards to making musical instruments? And what effect might there be on the stability and sound of the instrument?

Forum Responses
I remember reading somewhere that logs used for making Stradivarius violins were submerged under water for something like 50 years! Don't think I'd call that speed drying though.

I've heard that wood which is air-dried for 25 years is best for violins. Slow drying, nature's way, if you have the time, is best.

The drying rate does not influence the musical quality of the wood. The only possible point with time is that wood undergoes what is called viscos strain, or release of stress by a mechanism that takes time. The drying stresses that occur in all drying, fast or slow, can be released over a very long period of years. The sooner it is dried the longer you have for these stresses to be relieved. However, a few months more when talking about years is not much help! Try looking for sound lumber from old buildings that are dry.

Logs that have been submerged indeed make much better musical instruments than "fresh" logs. I suspect that this has to do with bacterial action that creates increased porosity of the wood (among other things).

We do know that slow air drying will result in a different product than fast drying, in some cases. For example, if white oak is air dried for two summer seasons, the wood will develop a vanilla odor, rather than the acrid odor of oak. I suspect that other species will also have chemical changes.

Also, it is possible that there is some bacterial action. So, I would believe that slow air drying for 18 months or so will develop a different musical behavior than fast drying. But is it better?

Again, the submerging is probably more related to bacterial action.

Gene Wengert, forum moderator

Have you considered the fact that Stradivarius and Fender, initially, were using logs which today would be considered old growth?

Old growth logs typically have 20-40 growth rings per inch but 70+ is not unheard-of (compared to new growth trees which may have as few as 4 rings per inch). I am no expert on musical instrument sound quality, but am sure the excellent acoustic properties attributed to the instruments made by these historical figures are somewhat dependent on the character and quality of the wood was used during fabrication.

The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

Comment from contributor A:
The release of stresses in wood or any material will allow for a more mellow sustained tone. I know this because I have worked with a cryogenic process where stressed materials (brass, bronze and wood) are slowly 1F per min. down to -310F and soaked at that temperature for 4 to 36 hours and then brought back to ambient temperature 1F per min. This makes formed and pressed metals have a much smoother tone and less susceptible to cracking by a large margin. Steel strings last 5 times longer with very little corrosion and a more even stretch along the complete length over playing time. They also resist fret dimples. Wood in this process is much the same, but more susceptible to damages during the process as it is a relatively inconsistent material.

Comment from contributor G:
You can't get to -310 unless you are using liquid hydrogen or liquid helium. Either one of these are far too expensive to use for these processes. Yet the temperature indicator used may be out of calibration. Regardless, cryogenic stress relief more than not is often claimed to be something it's not.

I have been in the cryogenic industry for 35 years and I still can't say that actual results are ever given to clients. I often see people using cryogenic (usually liquid nitrogen LN2) liquids for something they were told would help, but just as often they are disappointed.