above: 4th branch Yamaha YSH-411
Today I was dissecting a Yamaha YSH-411 brass Sousaphone for dent removal. I had a bit of trouble getting the 4th branch to come apart. After a little heating and gentle tapping with a rawhide mallet, it finally gave. What did I find inside? It looks like a tip to a cane, walker or chair. Here are a few more pictures of the item after I removed it.
The Yamaha YSH-411 is Yamaha's only brass Sousaphone. It has only been production since 1990. Yamaha also produced this model for Bach until about 1997 under the model number 1111.
The YSH-411 is essentially an attempt to copy a 20K, but with long action valves. The YSH-411 is unique from other Sousaphones because the branches are held together with hex head screws, so you can easily take it apart for repair. Amongst some it is debatable whether this is actually a good thing or not. In my opinion, it makes for a quicker, better repair and you can guarantee that there is actually a seal when you put it back together.
The valve cluster is removable, which isn't unique to Yamaha but is convenient for annual cleanings and valve alignments.
What also separates Yamaha from most Sousaphone manufacturers is the high tolerances used with their pistons. They are always very tight and smooth. Yamaha also uses an excellent coated valve spring that has excellent tension and is whisper quiet because of the coating.
Some have criticized Yamaha Sousas for having softer metal than other Sousas. This is probably true when comparing the Yamaha to an old King or Conn, but I think that the softness in the metal contributes to the sweetness in sound you can get from a Yamaha Sousaphone, which is a good thing. However, I don't honestly think that a Yamaha is any more prone to damage than any other new Sousaphone. This is just my opinion of course.
Here are the specs for Yamaha YSH-411
Bell Flare: 26 1/8"
Bore Size: 0.728"
Bell Collar: 7.25"
Weight: 27.6 lbs