Posted by Joe Baker on February 02, 2001 at 11:35:53:
In Reply to: Re: Re: Re: cryogenic tuba freezing posted by Cryotuba on February 02, 2001 at 01:23:48:
I have tried to resist the urge to cast in my uninvited two cents on this, but I just can't hold it back anymore. The last time I chimed in on this subject, it was to offer 'remote cryogenics' by having the customer put the horn in a closet in his home, send me a check for $100, and not open the closet and remove the horn until the check clears, giving the same results for less money and with no shipping. I got some not-so-humorous E-Mail replies, to which I responded with the following explanation:
There is a very real difference between copper alloys, like brass, and iron alloys, like steel. In particular, steel has certain specific matrices (in its solid form), the most common of which are austenite and martinsite. Martinsite is much harder than austenite, and is largely formed when, at the end of the forging process, the steel is heated to its quenching temperature (about 1350 degrees F) and then rapidly cooled by quenching. This is what is referred to as 'tempering'. However, a fair amount of austenite remains. It has been discovered (and proven) that cryogenic treatment furthers this transformation, making the steel harder. For this reason many STEEL items, including drill bits, engine blocks, springs, etc. are cryogenically frozen, with measurably beneficial results.
Brass, however, undergoes no similar transformation when cooled, either from high temperature to room temperature, nor from room temp to cryo. This can be seen by the fact that annealed brass can be cooled slowly or rapidly with the same effect, and has been demonstrated by microscopic and other sorts of testing. There is NO objective evidence that cryogenic freezing changes ANYTHING in the brass. The only measurable change is in the bonding of dissimilar metals (i.e. brass and lead-tin solder), which is diminished. Now many fine musicians and fine human beings declare that their instruments get better; perhaps there is some change that no one can figure out, or maybe weaker solder joints are better in some way. Or, perhaps (have you guessed that this is my theory?) there is a placebo effect at work. After all, when you are separated from your instrument for a period of a week or more (including shipping) and separated from $200-$300 of your cash permanently, or if there is a big fat endorsement check available, or if you've just spent a few $K on cryo equipment that needs to pay for itself and then some, you really, really WANT it to sound better. Not that anyone is being dishonest even (though that may be possible in some cases), but whenever possible the subconscious will lead us to believe that which is in our best interest. These improvements are PURELY SUBJECTIVE and SUBTLE. You think it sounds different, but by the nature of the process you have to be away from the instrument for several days. It's not exactly back-to-back, you see? How could you tell, several days later, if the change is real or imagined??
I say again, I accuse NO ONE of being dishonest or deceptive. I'm just saying that, until someone can explain to me a REASON that an instrument would get better by being frozen, it's snake oil in my eyes.
Joe "Here come the angry E-Mails again" Baker