Olds Symphony Trumpet
F.E. Olds & Son introduced their Symphony model trumpet in
1933, about 5 years after their first trumpets.  They had made
Symphony model trombones for more than a decade before.  
These were the largest bore and bell tenor trombones they
offered, so it is not surprising that the Symphony trumpet was also
a larger bore than the standard trumpet that preceded it.  From the
start it was offered in two valve bores: .460" (M SYM) and .468"
(SYM).  Some earlier Olds trumpets shared these bore
measurements, but the Symphony has a newly designed bell that
was larger through the final flare than the previous large bell as
seen on the early
"LM" trumpet.  This was the first model with a
name other than "The Olds" and "M", "LM" etc. and it also seems
to coincide with the introduction of the
first Olds cornets.  These
conclusions are based on the data collected by Eric Hamlin in his
The Olds Register, and more data may change them.  

The photos clearly show that this example has a gold or red brass
bell (higher copper content).  I haven't determined if all Olds
trumpets have the same alloy bell metal, but they certainly did use
other than standard yellow, or cartridge brass as we see in most
trumpets today.  It is the "M SYM" (medium symphony) model
with .460" bore as indicated above and with a serial number of
1374, was made in 1934.  It is 19 1/8" long (18 15/16" from bell
rim to bell curve) and the bell rim diameter is 4 5/8".  The last
image to the left is a page from a catalog from about the same date.

Click on images for larger views.