What exactly is a COA?
Clean: Easy! Any repairman can clean a flute.
Oil: Easy! Any repairman can oil a flute.
Adjust: Woah. Here's where things get complicated. The adjust part of your COA could range from turning a few adjustment screws, to re-shimming every single pad on your flute. For most technicians, even for many who charge more than I do, it means simply making the flute play.
Here's what I do to "adjust" the flute: I make every single pad seal better than it did when brand new from the factory.
I use a mag machine, a tool which measures the air pressure that a pad is capable of sealing. That gives me an objective, scientific reading of how well each pad is sealing with exactly 65 grams of force applied to the sprung key (simulating playing the flute with a very very light touch). I know the readings that correspond to "Acceptable," "Good," and "Insanely Good." The "acceptable" reading is the average reading on a brand-new flute of that type, basically it corresponds to the factory's standards.* The "good" reading is what I achieve in a COA, it is better than factory-new and it will make the flute play perfectly. The "insanely good" reading is only possible with brand new pads and is what I achieve on an overhaul, but it is not possible to distinguish from the "good" reading when actually playing the flute.
At Rich Lupo Flutes and Piccolos, a COA means that your flute's pads will objectively, scientifically seal better.
Speed: Virtually all technicians will quote "a day or two" for your COA. It's reasonable, but they are not spending that entire time working on your flute. You know that; there is always processing time included in there. But exactly how long does it take to do a COA? Well, it depends on how much effort goes into the "Adjust" part of the COA. Most technicians are perfectly happy to make your flute play like new, or what my mag machine measurements would mean "acceptable." That takes about 3 to 4 hours of labor to achieve "acceptable" results from a COA. For me, I like to make the flute play perfectly, which means achieving my "good" mag machine numbers, which are better than a new flute. That takes 8 to 10 hours of highly skilled labor.
*The people who put the pads into a new professional flute at a flute factory are called "finishers." That is usually an entry-level position, usually paying about $18/hour. This is why new flutes almost never play as well as they possibly can. After several years of experience they may set out on their own and become a professional flute repair technician, though there are additional skills needed for repairs than just finishing. An experienced repair technician can "go further" than the finishers, though it takes a little more time, and make the flute play better by making each pad seal better than "acceptable."
Clean: Easy! Any repairman can clean a flute.
Oil: Easy! Any repairman can oil a flute.
Adjust: Woah. Here's where things get complicated. The adjust part of your COA could range from turning a few adjustment screws, to re-shimming every single pad on your flute. For most technicians, even for many who charge more than I do, it means simply making the flute play.
Here's what I do to "adjust" the flute: I make every single pad seal better than it did when brand new from the factory.
I use a mag machine, a tool which measures the air pressure that a pad is capable of sealing. That gives me an objective, scientific reading of how well each pad is sealing with exactly 65 grams of force applied to the sprung key (simulating playing the flute with a very very light touch). I know the readings that correspond to "Acceptable," "Good," and "Insanely Good." The "acceptable" reading is the average reading on a brand-new flute of that type, basically it corresponds to the factory's standards.* The "good" reading is what I achieve in a COA, it is better than factory-new and it will make the flute play perfectly. The "insanely good" reading is only possible with brand new pads and is what I achieve on an overhaul, but it is not possible to distinguish from the "good" reading when actually playing the flute.
At Rich Lupo Flutes and Piccolos, a COA means that your flute's pads will objectively, scientifically seal better.
Speed: Virtually all technicians will quote "a day or two" for your COA. It's reasonable, but they are not spending that entire time working on your flute. You know that; there is always processing time included in there. But exactly how long does it take to do a COA? Well, it depends on how much effort goes into the "Adjust" part of the COA. Most technicians are perfectly happy to make your flute play like new, or what my mag machine measurements would mean "acceptable." That takes about 3 to 4 hours of labor to achieve "acceptable" results from a COA. For me, I like to make the flute play perfectly, which means achieving my "good" mag machine numbers, which are better than a new flute. That takes 8 to 10 hours of highly skilled labor.
*The people who put the pads into a new professional flute at a flute factory are called "finishers." That is usually an entry-level position, usually paying about $18/hour. This is why new flutes almost never play as well as they possibly can. After several years of experience they may set out on their own and become a professional flute repair technician, though there are additional skills needed for repairs than just finishing. An experienced repair technician can "go further" than the finishers, though it takes a little more time, and make the flute play better by making each pad seal better than "acceptable."