こんな記述も見つけた。
ttp://hiperhip.blogspot.com/2007/02/strange-story.html

"National Philharmonic Symphony Orchestra" (省略) "It should be evident
that such a name for an orchestra is just a concoction of the terms that
are more commonly used when naming ensembles: "national," "symphony,"
"philharmonic." But "Philharmonic Symphony Orchestra" is almost a
redundancy (one might claim that "philharmonic" and "symphony" are synonims,
but there is a subtle difference between the terms).

要旨："National Philharmonic Symphony Orchestra（ナショナル・フィルハーモニー
交響楽団）"とやらが録音したことになっているが、オケの名前としては、
よく使う言葉をつなげただけで、無駄に長い。なぜなら、"philharmonic"と
"symphony"はほぼ同義であるから。