Auto-tune is a well understood concept, a waveform is analyzed then pitch shifted to the nearest neighbor in a fixed scale.
Imagine an instrument, in this case the humble tuba. On the main tuning valve, a servo motor is attached. A calibrated reference microphone would be placed in the bell.
For those of you who know brass instruments certain notes are natively out of tune due to the harmonic principles. High level players will adjust tuning slides to compensate for these out of tune notes.
This reference microphone would listen to the frequency and match it to the closest note by automatically adjusting the main tuning slide faster than any human could. Going to your child's recital would no longer require earplugs or cotton balls!
For extra credit you could add limit switches under the valves, so when you did valve 2+3 on a tuba or trumpet it would automatically compensate before the note is sounded.-- metarinka, Aug 20 2011 This could also be done on string instruments by tightening or slackening the strings (auto tremolo?) and could be done on a piano in a similar fashion albeit with more difficulty-- metarinka, Aug 20 2011 When I saw the title, I thought this might be an idea for a automated Tuna and Sheep duo device.-- xenzag, Aug 20 2011 I bet some really wild guitar effects could be created by servos that could be used to alter the tension of individual strings at the touch of a button; sort of like a single-string digital whammy bar.-- Alterother, Aug 20 2011 You could really freak out a trombonist by fitting one of these surreptitiously.-- MaxwellBuchanan, Aug 20 2011 There's a tuning valve on a trombone? I thought they just had a spit valve.
<A short time later, [The Alterother] consults his wife, the Good Fairy Jenny, who amongst other things is a talented musician.>
The Good Fairy Jenny says she's not sure.-- Alterother, Aug 20 2011 Trombones typically have a tuning slide, separate from the main slide, that's what would get tweaked. The alternative would be to have it mounted between the handle and the main slide, which is what I think [MB] was talking about.
(For the record valve trombones do exist, but they aren't what you would think of as a trombone. Also some tenor trombones have an "F" attachment that changes tuning on the fly, and that uses a single valve).-- MechE, Aug 20 2011 trombones tend to have f and even e flat valves to help with tuning and to reach 5th and 6th position faster. And yes they have a tuning valve, because you would still want 1st position to be in tune.-- metarinka, Aug 21 2011 Ever hear the sour crout band?
Great for violins if the kids play the fingers correctly. Useless with clarinets. Fun just thinking of it. Btw today all players have a digital tooner so kids concerts should be easier on the ear. Are they?-- pashute, Aug 21 2011 as someone who played tuba for 12 years: yes everyone has a cheapey digital tuner, it still takes years of development before a young player has anything close to good ears and can play in tune. Some notes will be naturally out of tune (2+3 figuring) and thus they will always be out of tune and require the player to adjust the valve slide. Trumpets have key rings and can adjust the tuning on the fly, but that's an advanced technique.
Very few tuba players adjust their valve slides while playing, sometimes it's impractical-- metarinka, Aug 21 2011 //cotton balls//
I disagree. Going to a young children's band concert requires brass balls for sure.-- DrWorm, Aug 21 2011 random, halfbakery