TromboneChat

Looking at getting a King 2b. Not real sure if it is a 2b due to no marks on the bell other than King with crown. Does have the curved bell brace and the water key on the side of the slide. Serial number is 10XXX. Bell and slides all match. I know for a fact the tuning slide is a replacement

Anything I need to look at to determine the true age?

King used 6 digit serial numbers on all instruments after around 1925. At that time there was no 2B. A King with a 5 digit serial would probably have a double brace on the inner slide with one straight brace and 1 arced brace. This was in use from around 1907 to 1925 (dates approximate). Horns made before World War II did not have a simple crown/King engraving -- it was much more elaborate. In fact, the Crown/King engraving generally started in the 1960s or 1970s.

There are more than a few things that don't make sense unless you can give us some pictures, we may not be able to help.

Note that there is a curved brace Tempo, 1306, that isn't a true 2B, but is a very popular instrument, especially for Latin bands where a lot of volume is generally needed.

I have a horn that sounds similar to what you're describing. Check these posts. Maybe will get you closer to some useful info?

viewtopic.php?p=253391#p253391

viewtopic.php?t=6325

Here are some pics

Water key might give it away as a Jiggs Whigham 2B, at least the slide section

Is there any marking on the inside of the bell?

No marking in the bell

The tuning slide weight looking like a 606 with the king logo and crown. It does not look original