"I've heard references suggesting that certain mouthpiece and trumpet combinations are better than others in terms of maximizing overall results. A synergy perhaps? I assume this is meant in terms of intonation, resonance, resistance, etc.

I assume the only way to really determine the best combination, assuming the trumpet is the constant and the mouthpiece is the variable, is by trial and error. But I wonder if anyone has studied this before in a controlled setting and came to quantifiable conclusions that could be used to get a player in the ball bark as a starting point.

Specific to my own set-up, I'm playing a mid-70's vintage LA Benge 5X, ML bore, with a stock Schilke 15C4, which is pretty close to a Bach 3CW(ide). I'd like to have a bit tighter intonation without having to work so hard at it, the 5th partials, i.e. D, Eb, E, are quite a bit flatter on my horn than I'd like, which got me to thinking about horn/MP combination. "

GR: The mouthpiece, player, and horn must be a match.

This phenomenon is acoustical in nature. This system determines how the pressure/standing wave is set up. There are no rules set in stone because people vary. There are trends that are common to certain horns and mouthpieces, although, when we measure each horn these trends may or may not apply.

We at GR have come up a series of tests using the laws of physics to determine how efficient the system is working.

This usually begins with checking certain measurements of the mouthpiece, the horn, and the relationship between them. On certain occasions there are times when we measure how the lips are held in the mouthpiece. At that point we do a few simple tests to determine what is happening. Understanding the physics of the trumpet and the lips will play a major role in this decision.

There is a basic understanding physics that is required. Every maker has his or her own interpretation on this subject. The trumpet compresses the harmonic series. The most important part of the trumpet is the bell. This sets up the reflection of the pressure wave. The bell raises the lower partials.

If you take a piece of cylindrical/straight tube and add a bell flare, the lower harmonics are raised. Adding the bell; This is done to move the lower modes up. By flaring the end to a larger diameter (shape is very important) the BELL raises the frequencies of the lower resonances, the lowest moves the most. Length must be adjusted.

The shape of the bell has a major effect on intonation.

If the bell is bad a good mouthpiece and leadpipe will not make the horn any better. The mouthpiece volume determines pitch, not the length. It is non linear in shape. The mouthpiece has a first natural frequency. The First Natural Frequency may be different for each player even on the same mouthpiece depending on the amount lip engagement. Lip engagement reduces volume and will raise that First Natural Frequency.

The mouthpiece lowers the upper partials. If you have a straight tube and add a mouthpiece the upper partials will come down and this will add to the compression of the harmonic series. (When the mouthpiece is added to a piece of cylindrical/straight tube we calculate the volume of the mouthpiece. The equal volume of cylindrical/straight tube is removed. The lowest resonance frequency will be unchanged but the upper will come down.) The Leadpipe taper is an extension of the mouthpiece. The Gap must be in the ballpark. This gap measurement is critical and must be set correctly; usually +/- .02 is close enough for good results. A good leadpipe will not hurt your horn. A bad leadpipe will hurt the horn. Your horn is only as good as the bell. Bells can vary in manufacturing, design, and especially when damaged.

" Specific to my own set-up, I'm playing a mid-70's vintage LA Benge 5X, ML bore, with a stock Schilke 15C4, which is pretty close to a Bach 3CW(ide). I'd like to have a bit tighter intonation without having to work so hard at it, the 5th partials, i.e. D, Eb, E, are quite a bit flatter on my horn than I'd like, which got me to thinking about horn/MP combination. "

GR: I played a Benge 5X about the same vintage as yours on the road in the late 70's. I played many 5X's and mine was a good one. From information that was given to me years ago this horn was suppose to be more free blowing than the 3X. I was told they took a 3X bell and pushed a larger ball through the small end of the bell to open it up. I am not sure if this is true but it makes sense. I never verified this because the horn did play well and it didn't matter at the time. If this expansion was done incorrectly (wrong size ball etc.) it could have an effect on intonation.

Has the bell been damaged? You may want to check the Gap. With that Schilke mouthpiece it should be around .125". With newer mouthpieces the Benge horns usually have a gap that is too large. With a GR Mouthpiece .125" to .156" would be a good starting point for the gap. Optimum gap from my prior knowledge of that horn with a GR Mouthpiece would be about .140". The Schilke would require a slightly smaller gap if the exit diameter in the backbore is larger than the GR and the shank O.D. diameter is less. This would reduce the exit wall thickness of the Schilke mouthpiece. If the exit wall were less the overall gap would be less as per our Gap Formula. If you are in the ballpark then going through our testing may reveal other problems and possible answers.