Does the....(at it again, ain't I ?!?)

......sound of metal change in relation to it's temperature [whilst in a solid state ] ?

For example, does the tuned note of a tuning fork actually change at certain temperatures ?

 

Well doing a quick bit of googling I came up with this statement in regards to musical instruments.

"Fifthly, this material is so bad a conductor of heat that ebonite flutes are far less affected than any others, in their pitch, by alteration of temperature."

So it appears that the temperature of a metal will influence it's sonic characteristics. Which is logical, since if you think about it, heating alters the molecular structure of the substance and so it's properties.

Anyway hope this helps to answer your question.

 

Cheers !

I had thought of what you mention but as the actual mass of the metal would remain constant I thought that this may determine if any affect would be noticeable/measureable.

 

Temperature change will obviously affect the density, which I think affects the stiffness. I seem to remember stiffness and mass are two of the key properties in vibration.

Thats just from my bad memory though....

 

Well, yes, because length will change with temperature, thus altering the period of vibration and therefore the note produced. Now, whether any human ear can ever detect such a change is something else again...

 

I use to have flute lessons at school and we were taught in groups of about 5. Now, at the start of each lesson we would tune up and made sure that we were in tune with the teacher's piano - to tune up we would move the head joint on the flute either further in or further out depending on whether we wanted to sharpen (raise) or flatten (lower) the pitch.

It was particularly noticeable on very cold winter days when we'd bring our flutes into a warm class room from the frosty outdoors (there was this one time... at band camp... ) that the tuning of our flutes would change as the lesson progressed. We had to move the headjoints just slightly in or out to keep the relative pitches of our instruments in tune with each other i.e. it was changing as the flute was warming up due to our breath/condensation. In the case of the cold flute, it would be lower in pitch and get slightly higher as it warmed up; to correct this we would have to move the head joint outwards to make the length of the instrument longer and hence lower its pitch. The variation in pitch was noticeable enough that we would each appear to be slightly out of tune with either the piano or each other as the lesson progressed.

 

Cold drums and cymbols in me mate dad's garage, always seem to have a heavier thwack to them

 

Re: Re: Does the....(at it again, ain't I ?!?)

Now, does the conductivity of metal change enough, in relation to temperature, to have a discernable affect on the signal being passed through said metal* ?

*If part of an electrical circuit in say....a CD Player/Amp.

 

Re: Re: Re: Does the....(at it again, ain't I ?!?)

I don't know, but my guess would be no. The conductivity of metals does change with temperature, but (a) the temperature difference between ambient and operating temperatures would be relatively small, so the difference wouldn't be great, and (b) the signal as a whole would be influenced by any change in conductivity, so there shouldn't be a difference. But, as with fancy cables and other reptile-derived oleaginous substances, if you're determined to hear a difference, you will!

 

I would say Tones and HenryT are right. It is the length of the vibrating body that matters.

This is quite noticeable (and listenable) with big organs. If you take a look at the organ on my avatar you'll see the façade is spread in height. Some pipes sound at the top of the organ, others are near to ground level. In this particular organ the difference can be as large as 15 meters.

Now, as you all know, heat travels upwards. When a church is full of people, heat rapidly concentrates at the top of the church. In consequence the pipes dilate and go out of tune - they get lower in pitch.

Is it noticeable? It most definitely is. But as each department of the organ tends to be used by itself, differences are not disturbing.

Now when the upper department of an organ has both wooden and metal pipes, that can get worse. Wooden pipes just don't change their pitch with temperature (their volume does not increase) whereas metal ones do - their pitch lowers. And there is where you get problems.

With central heating these days, the problem has been either solved or made much worse - it all depends on the air flow.