TromboneChat

Kia ora, I am pretty new to trombone (although I play other instruments). I bought this trombone at an estate sale and the seller knew nothing about it. It's an Imperial by Boosey and Hawkes, at least 70 years old. It's got a bore size of about 13.5mm, the bell is 190mm. It has a handle to reach the further positions (I can only reach 4th without the handle!).
It's a beautiful instrument and I love it, but I'm struggling. 1st position is giving me a G and a C# (top one (my top, I don't have a very big range yet) I can get a Bflat). Am I just playing really sharp? I'm not used to the massive mouth piece.
Is this a bass trombone or a large-bore tenor? I'm not sure of the difference since this one doesn't have an f attachment.
Any advice much appreciated!

It sounds like you have an old G bass trombone. They are interesting instruments (I have one!), but much more unwieldy than a tenor or modern Bb bass trombone.

If you are just starting out on trombone, I would recommend finding yourself a good used tenor trombone, which we can certainly help you with here. It'll be much better for your development, and most likely be more fun. You could keep the G bass for fun, or sell it to help pay for a tenor. Up to you.

Pictures might help, although you will need 3 approved posts to be able to post them.

From your description, you have an English G Bass trombone. If it has a valve, the valve would be in D.

You have the large bore version; there is a small bore version that is something like 12.5 mm.

While this is called a bass trombone it normally uses a mouthpiece like a Bach 6½ AL. Lowest note is a C# below the bass staff. You will have trouble using this for modern bass trombone parts.

Another potential problem is that many of these were made in High Pitch (A around 450 Hz) and so it would be difficult to play in tune with modern instruments tuned at A=440Hz. It will seem almost 1/2 tone sharp.

Bruce (and Finetales) is spot on. Its a G Bass Trombone... I've got 2 they have their moments but I wouldnt advise anyone to learn on one - Doug