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I was just curious to see what you guys think about this. I have heard many different opinions/answers about how bad a dent/scratch has to be until it is no longer cosmetic such as so much of the airway blocked. I have also heard ANY...ANY puny little tiny tiny nick on the valve casings will affect playing.


Argue away!

It's a matter of degree. The real question is not whether a ding or dent matters. It does. By definition you are doing something to the horn, so it makes a difference. The question is how big does it have to be to make a noticable difference. Somewhere between your belt buckle scratching the lacquer and completely flattening a bow you will start to notice it. At that point, have that one fixed. Different people notice different things, and depending on where the dent is, and especially if it is close to a node, it might look horrible and be sonically insignificant, or look tiny and have a very noticable effect. As each person and instrument is different, there cannot be any hard and fast rule, except maybe that dings in the valve block are more noticable because there might be complications that whatever force caused the dent might have gone through the block and caused other problems, and because little dings in the block tend to have their effect multiplied due to the effects of the wrap, spit keys, ferrules, valve ports, etc.

My view is, how much of the active instrument are you changing? I don't think that the same change will affect a trumpet, euphonium, or tuba the same way. For example, a 1/2" dent on a critical node point is much more of a percentage of the total air column in a trumpet than it is for a trombone of euphonium, let alone a tuba!

Any dent that pops through to the inside of the valve casing is most likely going to stick the valve, A LOT.

I dropped the top of a Manhasset stand on my 4th valve casing (long story, stands fault and not mine). There is a dent/scrape, but it doesn't go through to the inside so there is no effect.

Dan Perantoni use to tell the story how he once had an Alexander get dropped and damaged while being loaded on a ship. He claimed the resulting dents greatly improved the intonation. So maybe some dents do some good!

There are a lot of stories about denting to improve a horn's performance.

Denis Brain stuck a broken wooden matchstick in his horn to improve response of a particularly bad note.

There was supposed to be a guy in Germany who used to dent Alexander tubas at nodal points to improve the intonation.

I've also heard some trombonists talk about a Clear Nodal Overlay Chart and Dentonation Hammer sold by the Tia Brothers.

tofu wrote:Dan Perantoni use to tell the story how he once had an Alexander get dropped and damaged while being loaded on a ship. He claimed the resulting dents greatly improved the intonation. So maybe some dents do some good!

Hey! I resemble that remark! They can, no different than adding/changing bracing, thickening metal, etc. as a dent will create a stress, and if near a node, can definitely affect intonation.

See also:
viewtopic.php?t=14859
as well as others on the topic.

Allthumbs wrote:The only true advantage to relic treatment is that you don't lose additional resale value when you cause cosmetic damage

The problem is, you may actually cause it to look better than when it came "pre-stressed"!

Brian Guppy wrote:

Alex C wrote:There are a lot of stories about denting to improve a horn's performance.

I knew a trumpet player who had a small dent removed - when he got the horn back one note was particularly stuffy. He just went ahead and put the dent back in and that solved the problem.

I would be interested to know if tuba manufacturers would ever actually consider delivering horns from the factory with strategically placed "imperfections" to help intonation / response / whatever. It doesn't seem wildly unreasonable to believe that there are issues that can best be solved by having small sections of tubing with a non-circular cross section.

This might sound a bit off topic, but it deals with frequency - which is what intonation is all about.

When I was a radar technician in the Air Force in Greenland (1968) we had a technical inspection. The inspector wrote up a piece of wave guide which connected the magnetron to another piece of wave guide going up to our antenna. This piece of wave guide had a dent in it that looked like it was hit with a ball-pinned hammer. [For those who don't know, a wave guide is a transmission line used for high frequency with low attenuation so power is not lost. Wave guides look like square tubing or enclosed channels (this was 10cm radar)] We ordered a new piece of wave guide to correct this inspection item. When the new piece arrived, we were surprised to see a very similar dent in almost exactly the same spot. When we called the company (Gilfillan Corp), we found out that these dents were placed there on purpose by an engineer to improve the VSWR (voltage standing wave ratio)... or shift a node so to speak. Running RF (2800 mhz) frequency thru the WG he would press in certain areas until he found an improvement in the VSWR, then indent the wave guide there.

I can understand how a dent may help certain notes like iiipopes and Carroll have explained in other threads.

Hey, Rick F -- thanks.

Oh, BTW to the rest of TubeNet: his comments are NOT an encouragement to take a ball peen hammer willy nilly to your tuba! If you do not understand nodes and frequency theory, you can really foul up your horn in a big way!

Hey, Tubatuck -- sorry to burst your bubble. OTOH, I smile when I see your signature. Definitely an original application to the Beatles' lyric off Abbey Road! As a Beatles' fan (yes, that's why I play guitar and bass as well) I like it. A lot.

Actually, from what I've seen on interviews, like when Paul toured Russian schools, I think if done well he'd appreciate it.

Hmm. To get the feel, try arranging Norweigian Wood in concert F (major on verse, minor on bridge, of course), to be played on an Eb tuba so that the contrasting keys really come out (second valve A natural will be really bright compared to 1st valve A flat), and then if you want to transcribe a different accompaniment it will be easier than the E major/minor, and if you still want the feel of acoustic guitar chords, all the guitar player has to do is capo at the first fret and use the same chords as on the record.

iiipopes,
You have got to move to Alabama. You got it figured out, guy and there is work for you here.
Enjoy your posts.
Beers to you!