About Bob Osmun

We run a small music shop specializing in brass instruments, especially horns. We sell Engelbert Schmid, Finke, Hoyer and Alexander horns and have a world famous repair shop staffed by three of the best technicians in the trade. We regularly perform valve rebuilds, screw bell conversions and manufacture our own line of trumpet and horn mouthpieces. Jim Becker, our trumpet specialist builds custom trumpets and does all sorts of trumpet modifications.

Why do some trumpets play better than others?

As far back as I can remember, it’s been an article of faith for trumpet players: To get a good trumpet, go somewhere where you can try a lot of identical instruments and pick out the good one. That used to work, sort of. Years ago, large stores and even some smaller ones carried multiple samples of the same instrument which they would dutifully roll out to be tried. The problem was that, unless you happened to be there when a new shipment arrived, you could safely assume that the trumpets you were trying had already been picked over by numerous players. Plus, it can be very difficult to access small differences in a short time span and in an unfamiliar acoustic. Nowadays it’s pretty much a moot point. The economics of the music business make carrying a large stock of instruments a losing proposition.

So, what makes some trumpets good, others just OK, and a few real “dogs”? How do you pick out the best one? On the face of it, shouldn’t they all be the same? After all, they’re made in the same factory, out of the same parts, and by the same people. Why are they different? And what steps can you take to make sure you get a good one?

Every maker begins a product line with a prototype instrument or two. These instruments are made by hand, by the finest craftsmen available, and are tweaked and adjusted until they’re as perfect as they can be. It’s not surprising that they are very good trumpets. The question is: what happens when these instruments move from prototype to production? Do they maintain the same quality and if not, why not?

If the factory instrument differs from the prototype in its playing qualities it seems reasonable that it must differ in its specifications as well. The closer the instrument is to the original design the more likely it is to play as the designer intended.

There are a lot of places for an instrument to go wrong in the construction process. The bore can be obstructed by solder or burrs or constricted by a too-tight assembly, slides and valves can be too loose or too tight, valves may not be in perfect alignment. There are other, more subtle issues as well. The bell bow may have become flattened during the bending process, the mouthpiece receiver may not be concentric, or the venturi may be too small or large. Carefully measuring and correcting these defects restores the craftsmanship component to factory-build instruments and makes them play the way they were designed to.

We call this process Blueprinting, after the process used by racing engine builders. Blueprinting means bringing the instrument as close as possible to the specifications the designers intended. Obviously, it varies instrument by instrument, but a Blueprinting process might include:

  • Precision Valve Alignment
  • Rounding out the bell bow
  • Checking for and removing burrs in the valve cluster and water keys
  • Checking for and removing obstructions at the solder joints
  • Checking slides for fit and alignment
  • Checking and adjusting mouthpipe venturi and mouthpiece receiver

When we get your instrument Jim will examine it and recommend the adjustments that he thinks will make the most improvement. Usually, the work can be done in a day or two.

Same Day Service

 

Measuring Rims

Measuring Rims
Here’s a Lawson B23G705 rim. Its inner diameter is either .705″ or .683″, depending on where you measure it.

We’re often asked to compare the diameters of rims from different makers. Whether a rim measures 17.5 or 18 mm depends on where it’s measured. There’s no “right place” to measure a rim and unless the maker tells you where a rim has been measured it’s impossible to compare.

The Lawson rim shown above was measured at a point .025″ down from its high point (crown). That’s where the “705” number comes from. We think that’s a less-than-ideal place to take a measurement because it’s in the middle of the curve.

Osmun mouthpieces are measured .050″ down from the crown because at that point the rim blends into the cup. So, in our measuring system the diameter would be .683″.  That’s .022″ (.56mm) different.

Other makers may use different measuring points and unless they tell you where they’re measuring, it’s impossible to compare.  So, take rim measurements with a large grain of salt.

 

 

 

Introducing the Osmun Visualizer

Use your own rim! Our new embouchure visualizer features a Giardinelli-compatible thread so you can use it with your regular rim. It fits our rims as well as Giardinelli, Moosewood, Houser, and most other American screw rims. Also available: models for Paxman Halstead-Chidell, Lawson, and others.

 

Allergies a problem? We can duplicate your rim in Delrin or Lucite. Call 978 823-0580 or email for more information.

Cleaning Schmid Horns

Osmun Music has been servicing fine horns for almost fifty years. The chemicals and processes we use have been exhaustively tested and are safe and effective. However, we do adhere to Schmid’s repair protocols when servicing Engelbert Schmid instruments. That means no chemical baths are used on rotors and corrosion is removed by mechanical processes. We will be happy to explain the process in detail and respect your wishes.

Chem Clean or Ultrasonic: Which is Best?

Brass instruments have traditionally been cleaned with a combination of soaps and chemical baths, accompanied by a good deal of hand scrubbing. In recent years ultrasonic cleaners have come into the picture, offering a different cleaning method. Which method gets your horn cleaner, which is safer for the horn (and you)?  How do you choose?

valves-beforeAs a brass instrument is played, deposits build up on the inner surfaces. These include old grease and oil, food particles, dental plaque and bacteria, calcium, and copper carbonate, the material formed by the reaction of the acids in your breath and the copper in the alloy. Copper carbonate builds up green, rock-hard deposits. It’s the primary cause of sticking and other action problems in rotary valve instruments. If the mouthpipe is brushed out once a week or so and the instrument is oiled frequently enough, a brass instrument can go for years between Chem/Ultrasonic cleanings. In actual practice, however, this rarely happens and a cleaning is needed every year or so.

A Chem Clean starts with a scrub with brushes and detergents to remove old oil and grease. The instrument is immersed in a mildly acidic solution  which dissolves the calcium and copper carbonate. Areas of heavy buildup can be addressed with acids on a
q-tip. Then the instrument is scrubbed again with detergent to remove any residue and is re-assembled.

Ultrasonic cleaning replaces the hand scrubbing with sound waves. The disassembled instrument is put into a tank of cleaning solution and bombarded with sound waves. The sound waves cause microscopic bubbles to form in the fluid. These bubbles immediately collapse, converting the sound waves into kinetic energy. This process, called  “cavitation”, creates the scrubbing action that cleans the horn. One of the big advantages of ultrasonics is that that scrubbing action reaches all through the inside of the horn, even into areas unreachable by brushes.

valves-afterWhen using ultrasonic cleaners it’s important to be aware of their power and potential for damage. The microscopic bubbles are very good at finding their way into the pinholes left by dezincification and opening them up. So, older instruments and instruments that show any signs of dezincification (red rot) should not be ultrasonically cleaned. Ultrasonic cleaning can also remove some lacquers. So, it’s important to use the least power and the shortest time that will do the job.

Some people have the misconception that ultrasonics replace acids in the cleaning process.  This is not the case. The acids are needed to dissolve the calcium and copper carbonate deposits. The cleaning solutions we use are mild enough to be handled without gloves. We have tested samples for up to four hours of immersion with no measurable loss of metal. (Repair shops and manufacturers used to use Chromic acid to produce a bright brass surface. This material did remove metal and is also a carcinogen. It has been banned by the EPA although, amazingly, you can sometimes still find people using it.)

In our shop, a typical cleaning may involve both ultrasonics and traditional techniques. We choose the combination that’s safest and most effective for the instrument.

Schedule a Cleaning

Tuning Bits for Schmid Triples

schmid-bits

The bit on the left is standard Schmid issue. Our bits are .500″ and .750″ longer.

Like it or not, it’s still a 440 world. Many ensembles in the US are sticking resolutely to the old standard; in Europe, it’s different. Most orchestras tune to A=442, 444, or even higher. And European instruments reflect this.

It’s common here to see players of Schmid triples and descants playing with the tuning bit pulled out just about as far as it will go. In addition to the obvious stability issues, pulling that far out creates a long cylindrical chamber at a crucial point in the bore. This unwanted increase in bore can cause intonation, response, and focus issues.

The solution is obvious. We’ve made a couple of new bits that are longer than stock. This allows them to be played pushed further in. We’ve also created a longer taper and minimized the disruptions between different sections. Right now these bits are in the development stage. We’re gathering feedback from players and tweaking to optimize the design. When we have something that’s better it will become a product. Stay tuned.

Meet Genevieve

genevieve600

Genevieve is the newest member of the Osmun team.

We’re happy and excited to welcome Genevieve Rudolph to our team. Genevieve is a trumpet player and a student at Acton-Boxborough Regional High School. She’ll be answering the phone, helping with customers, and helping to keep our display instruments in tip-top condition. You’ll find her here on Saturdays and some weekday afternoons (when her band schedule permits.) We look forward to working with her.