Original_Username

So I've noticed that a lot of trumpets have different tuning slides.

It seems that the "standard" on most trumpets are the square tuning slide.

Next there is the Round tuning slide, and finally I've seen ovate (or oval shaped) tuning slides on some higher-end models (like the Edwards or Monette). Could anyone tell me the difference between them?

gglassmeyer

The difference for me is the resistance that you feel when playing. The rounded one has a very open and unresricted feel. The Square adds more resistance and feels more restrictive. I prefer the rounded one, but it's a personal thing. Fortunately my horn came with both rounded and square tuning slides. As for Ovate slides, I have no experience. You could go to a music store and try out a Conn Vintage One and ask them to let you try both slides so you can experience the difference and it doesn't cost you a thing except a trip to the store.

bagmangood

This might help explain a little:
Edwards :: Trumpets :: Tuning Slides

But basically it all comes down to personal preference
(and ye olde mental voo-doo towards what is helping you-physics discounts it from mattering as much as we often think it does)

rowuk

The difference is the tension in the metal and the bracing. There is no set characteristic because every model horn/brace is built differently and reacts differently to changes.

I wouldn't worry about it. If you find a horn that plays incredibly well, buy it regardless of the slide shape. I don't have a square slide for my Monette or a round slide for my Bach. They both are "open in blow character though. The differences have NOTHING to do with the tuning slide!

gglassmeyer

Rowuk is totaly correct! In my earlier post I'm interchanging the 2 slides in the same horn and there is a big difference. However horn A with a round slide vs horn B with square slide likely have too many other variables at work. Horn B may feel more open than A because of other factors than the tuning slide. As always, play as many as possible choose the one that suits you best.

Vulgano Brother

The idea behind the asymmetrical ovate slides, where the first curve has a softer bend than the second is not acoustic in nature, but comes from studies of fluid dynamics. Back in the 1970's, and perhaps earlier, Bell Labs and Arthur Benade knew that one of the things that makes it difficult to build usable wind instruments is because the instrument must follow the laws of acoustics and fluid dynamics (even though most of our air doesn't really pass through the instrument). I saw some German instruments built on this principle in Frankfurt in the 1990's, but with squarish bends. They were not at all amazing to play. I imagine that the mathematics would have to be just right for optimal results. Taylor, however has put some "impossible" angles into his horns, and they still work. Theory and practice don't always line up with reality.

loweredsixth

I always thought that the ovate tuning slides were an attempt to make only one "bend" in the tubing at that point. A square tuning slide obviously has two "bends". Supposedly, the air (or sound waves) move quicker with only one bend to slow them down instead of two.

I guess the round tuning slide can be thought of as one "bend" also, but a much longer one than the ovate.

brad361

Just had a rounded slide made for my Schilke S42. I think that it opens the horn up a bit, and maybe loosens slotting somewhat, as others have mentioned.

rowuk

The velocity of sound and the speed of your air do NOT change with the slide. The LIE of fast air is a myth that will not go away. A horns sound is based on its resonant character, that changes with every single brace applied. The pitch that we produce is a standing wave in the instrument. Very little air is required to maintain the wave once it has been started. We only need enough movement of air to keep the lips moving. Projection is not the air that you inhale bouncing off of the back wall. Sound waves travel (air particles bumping into other particles like dominos), not single air particles. That is why the perfect, fluid dynamic trumpets NEVER worked. Wrong principle!

A great player can inhale about a gallon and a half of air and can play for about a minute with that lung full. That is not a very intense stream of air.

loweredsixth

Then would it be fair to say that a bend in tubing causes a disturbance for the sound waves and that less bends in the tubing would create a purer sound?

There must be a reason rounded tuning slides play differently than square ones, right?