DIGITAL GUITAR AUTO-TUNER PROJECT

Your trumpet is too pretty. The bugler in Boy Scout camp played so beautifully that he could bring tears of joy to listen to him noodle. The camp bugle was battered from years of abuse, ans the Campmaster, a Presbyterian minister in real life, thought it a disgrace to his administration. He replaced it with a shiny new one, lacquer intact, a joy to behold. It sounded awful, with sour notes that resisted all skill. Campmaster refused to return the old instrument, claiming that he had disposed of it (a lie). The bugler, a fine trumpeter, was literally in tears, berating himself for not having his trumpet with him. Trumpeter and I retired to the woods with a variety of implements: a broomstick, pieces of firewood, and a blackjack made from a rock encased in six socks. We took turns "distressing" the poor bugle, at one point denting it in so deeply that we needed the broomstick to round it out.

Hearing the sweet sound again made Campmaster come running to gloat that the instrument was fine, that as he had said all along, practice would make perfect. Boy Scouts don't lie. Bugler said, "We fixed it" and proudly displayed the dents. "The prof helped." Thanks a lot!

Jerry

Please translate "brugly" for me. I'm still trying to learn.

Jerry

-- Engineering is the art of making what you want from things you can get. ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

Know what a Spoonerism is? "brugly other" :)

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active

Not just in reverse - by incorporating the pickup in an impedance controlled oscillator it can act in both directions at once. I doubt that losing a few % of the market (guitars with active pickups) would be an issue for such a niche market device, although guitars with ONLY piezos and pre-amps would be significant loss. Some guitars already come equipped with crude feedback built in for "sustain" (generally using separate pickups for sensing and actuation), but not selective enough for this application.

I only tossed in the concept to illustrate that there are other options (in the spirit of the discussion); if I really thought it was going to set the world on fire I'd probably not publish it here. And in any case, that's only a small part of the tuning loop - the most important bit is mechanically adjusting each tuner, which isn't likely to be automated until someone builds a complete low loss tuner block that actually replaces conventional tuners (rather than attaching to them). Even that isn't a big challenge technically, but as always, the guy develops the first one could lose his investment if the market isn't ready.

Tony (remove the "_" to reply by email)

guitar

don't

magnetic

active

Thanks for the clarification. I come from the acoustic guitar world, where the vast majority are piezo and/or pre-amps, rather than a niche market. For electric guitars, you are probably right.

OK, point taken.

Great story! What do you think made the difference? I've heard that removing lacquer opens up the sound slightly, but have never known anything good to come from dents. Any explanation?

How much did he vary the pitch by in the second example? I can change the pitch maybe a half-step either way on my French horn using embouchure, but not much more than that.

pitch

Partials on a french horn are so close together that it's hard to lip much before the horn refuses to play along and just moves to the next partial. One of the typical trumpet books (Maggio? Stamp?) has a series of exercises where you first finger and then lip down a half-step. Back in my serious days I took it down to major thirds.

Once you get used to holding your embouchure in spite of the horn not wanting to resonate, it's a lot easier to play those false notes. It's the only way to play the trumpet notes between low F# and pedal C with a

There was a Boston Pops concert on PBS a few years back with Arturo Sandoval playing a pretty ballad on his flugel - he played a number of notes below f# and they sounded fantastic: big, full, pretty. And the fact that 98% of the people listening didn't notice (or care) was the best part: it wasn't some gimmick to lay onto the kids at a clinic, he was just making music ;)

Kelly

As a fadder of mact some people say things verse visa.

pitch

I'm skeptical too. ...at least without losing all tone. A trombone (I was a t-bone player in HS) is a 2/3 straight 1/3 conical instrument (like a trumpet). A baritone (cornet) is the opposite, so has a lower Q and can be shifted more. I don't recall the straigh/conical ration of a freedom horn, but given it's lack of stright sections it has a low Q, which is why it's a bitch to play.

Dents lower the Q? ...allowing the _musician_ to play it as he wished.

Brass intruments are dominated by second and third order effects, so it's really hard to get conclusive explanations. Particularly when the player is an active part of the feedback loop (ears - chops - horn - sound). Often, a little resistance in the horn helps the player move more easily between the partials. Just as often, thinking that the horn will sound/play different/better is enough to make it so.

Kelly

I read in sci.electronics.design that Jon Harris wrote (in ) about 'DIGITAL GUITAR AUTO-TUNER PROJECT', on Fri, 29 Apr 2005:

I don't know exactly, of course, but more than an octave.

"Hi. I'm John Audubon. I watch birds." "Hi. I'm Bill Spooner. I watch birde."

;-) Rich

I read in sci.electronics.design that Rich Grise wrote (in ) about 'DIGITAL GUITAR AUTO-TUNER PROJECT', on Sat, 30 Apr 2005:

"Hi. I'm Rich Grise. I jotch bokes."

Dain bramage perhaps? GG

Gotcha! No need to sew me to a sheet.

Jerry

I thought I knew what I was doing when I did it, but (as always) I'm open to correction. I had read (and still believe) that because baroque horns were hand made, therefore slightly irregular in the bore, they had lower Q, making it possible -- though difficult -- to play without valves. (Horn players were the elite of baroque orchestras, usually seated on a raised platform as, I read, a mark of honor.) Baroque mouthpieces had relatively larger bores, too, making the player's mouth part of the resonant cavity. Valves were first used to make playing easier. It seems likely that when machine-made instruments made nearly impossible to play without valves, nobody noticed. I could do little about the mouthpiece, but it was easy enough to "modify" the bore. Not needing a section with valves, a bugle's bore is more conical than a trumpet's, hence more compliant to the player's skill.

That trombone that was pulled a long way: was there anything special about the mouthpiece?

Jerry

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Exactly!

Jerry

-- Engineering is the art of making what you want from things you can get. ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯