TromboneChat

ZacharyThornton wrote: ↑Sat Jun 29, 2024 11:25 am My God this thread is a shitshow.
Doug Elliot absolutely is one of the great experts on this topic.
This is continuing the “death of the expert” trend of the internet.
Ever wonder why no experts hang around here anymore outside of Doug? It didn’t use to be that way.

Doug has the patience of of a saint, and is always willing to answer questions and discuss things. I have one of his mouthpieces, and there was definitely a good amount of correspondence figuring out what would suit my needs best.

Also, a Bass trombonist I play with recently worked with him, and after a few tries, got the perfect mouthpiece for their playing. Feels better. Plays better. Sounds better than anything they have ever played. It was a "process", and that takes time. Too many people want a quick and easy answer for something that doesn't always have one.

In the past I have also directly corresponded with the late Scott Laskey, Karl Hammond, and Ivan Giddings regarding mouthpieces, and it is NOT a simple subject. I don't know why people seem to think it is. There is a ton of thought that does into that relatively small piece of metal, and there have been many designers over the past 150+ years who each had their own philosophies and design ideas. Just look at HOW MANY famous designers there have been over the decades, many of which worked with top level pro players to develop their skills, and many of which also represent lineages of mouthpiece designers.

Note that a lot of mouthpiece "theory" is by guess and by gosh since nobody making mouthpieces is large enough to actually do real research.

Bach, Pepe, Griego, Laskey, Stork, Marcinkiewicz, Warburton, and all the others, used to do things for people and collect anecdotes on what worked and what didn't. They collected these into a sort of "fact book". That became whatever lore was used in design of mouthpieces.

The problem is that since we are all different, what's ideal for one may not work for another. And we have only rudimentary knowledge of how this works.

By all means read up on this stuff and take it all with a whole shaker full of salt. There might be some insights there, but there is also a lot of hand-waving.

I can explain how an internal combustion engine works, but I certainly can't tell you if you will prefer a Toyota Camry or a BMW I5.

BGuttman wrote: ↑Sat Jun 29, 2024 1:58 pm
I can explain how an internal combustion engine works, but I certainly can't tell you if you will prefer a Toyota Camry or a BMW I5.

To reiterate, I wasn't asking if I'd prefer a Toyota or a BMW (I can make up my own mind on equipment), I was asking how an internal combustion engine works.

The intake valve opens to let in the air & fuel mixture, as the piston goes down, then the valve closes and the piston goes up to compress the mixure, then the spark plug sparks to ignite the mixture, pushing the piston down, and the exhaust valve opens as the piston goes back up. And all that linear motion is connected to the crankshaft by piston rods to become rotary motion, which also operates the camshaft above that opens and closes the valves.

The vibration introduced into the exhaust system resonates the air column just like a trombone, with reflected sound waves helping to pull the exhaust out of the cylinder, synchronized with the exhaust valve opening cycle. Just like lip vibration.
How's that for tying both subjects together?

And the muffler is a helmholtz resonator, to selectively dampen unwanted sound vibrations instead of amplifying them.

Dana check your messages.

tbdana wrote: ↑Sat Jun 29, 2024 3:00 pmTo reiterate, I wasn't asking if I'd prefer a Toyota or a BMW (I can make up my own mind on equipment), I was asking how an internal combustion engine works.

Well, here it is:

The sound on brass instruments starts with the vibration of the lips, which is commonly referred to as buzzing. The mouthpiece serves to focus the buzz and transfer the vibration into the instrument itself. The body of the instrument continues to focus the buzz and amplify its volume.

This Wikipedia article gives a pretty good basic rundown, but there are no "rules" and only exceptions: https://en.wikipedia.org/wiki/Mouthpiece_(brass)

If you want a video that is going go through every part of a brass mouthpiece and explain how it works, something of which there is little to no scientific study or consensus on, I don't think there is one. You will get videos on choosing a mouthpiece, on how people design a mouthpiece, as well as a good number of videos and articles by a few makers on why their design philosophy is better than everyone elses. How a mouthpiece "works" often is intrinsically linked to the design philosophy of the maker.

As for engines, anything beyond the utterly basic is also tied directly to the intended use.

Doug Elliott wrote: ↑Sat Jun 29, 2024 3:24 pmThe vibration introduced into the exhaust system resonates the air column just like a trombone, with reflected sound waves helping to pull the exhaust out of the cylinder, synchronized with the exhaust valve opening cycle. Just like lip vibration.

This actually reminds me of a problem seen a lot in the motorcycle world: deciding to change to a very open exhaust without taking into account the rest of the system. Less resistance does not mean you get more power, higher efficiency, or anything, because it's not a system that works that way. This is especially true on older motorcycles and some cars that still used carburetors, the tuning of which many have described as an "art". They are full of lots of air channels, and adjustments, and it takes years to learn how to properly tune one.

There is also a part called the "main jet", which has a needle that goes into it to control the flow of gasoline vapors. The jet has a venturi in it, and the only way to determine which size to use is experimentally, based on that particular engine and that particular exhaust system.

Many are surprised to learn that the main jet size choice also has to do with having the "ideal" mixture of gas to air. Too much gas in the mix and not enough burns, so you get fouled spark plugs. To little and the gas completely oxidizes and it but then you get too high of a temperature, melting your spark plugs. So it's a similar type of compromise often involved in instrument design.

Exactly. I'm familar with side draft carburetors like you're describing.
And yes, bigger exhaust bore is not better or more free flowing, actually it's the opposite, it becomes less efficient.

tbdana wrote: ↑Sat Jun 29, 2024 3:00 pm
To reiterate, I wasn't asking if I'd prefer a Toyota or a BMW (I can make up my own mind on equipment), I was asking how an internal combustion engine works.

2 Cycle is:
Swoosh
Bang

4 Cycle is:
Swoosh, swoosh, swoosh
Bang

The rest is commentary.

To send this thread off properly into a one way dark cloud, is there a trombone'playing proctologist or GI doctor that can contribute a suitable analogy to the science of audio flatulence...just how do people pass gas the way they do. Can't be as simple as wind volume or velocity followed by rim, bore, and backbore sizes...and what role does the colon and bum/bell size have in the finished product. I'll take my answer off the air because I'm sure I'm burnt toast here.

I actually did just find the 1998 Marcinkiewicz mouthpiece catalog, which actually does give a bunch of information on the design philosophy regarding various aspects of their design:

https://www.mouthpieceexpress.com/media ... -guide.pdf

OneTon wrote: ↑Sat Jun 29, 2024 4:27 pm

tbdana wrote: ↑Sat Jun 29, 2024 3:00 pm
To reiterate, I wasn't asking if I'd prefer a Toyota or a BMW (I can make up my own mind on equipment), I was asking how an internal combustion engine works.

2 Cycle is:
Swoosh
Bang

4 Cycle is:
Swoosh, swoosh, swoosh
Bang

The rest is commentary.

What about rotary?

Pulse jet?

Rotary engines are still Otto cycle. Jet turbine and turbine engines are internal combustion but not Otto cycle.