Using a horn rim on alto horn

We get a lot of inquiries from people about mouthpieces for doubling, especially between horn and instruments with similar size mouthpieces: trumpet, alto horn, mellophone. The following letter is typical.


My wife is a French Horn and Alto Horn player who tells me she would like an Alto Horn mouthpiece with a French Horn Rim.  She referred me to ******  who sent me to your website.  We play in the ***** Brass Band.

Her French Horn mouthpiece is a Constellation 7BW (picture attached).  Her Alto mouthpiece is whatever was in the case (Salvation Army loaner).  I can get that model if you need it.

How to proceed?

Here’s our response:

Hi Dan,

I think the best way to proceed is to first convert the alto horn mouthpiece to accept screw rims. You could then fit a new rim of whatever size or shape you wanted. You then have a number of choices:
1. Buy another Conn 7BW and have the rim threaded so that you could screw it onto the alto horn cup. Assuming the two Conn rims are reasonably identical, this would be the most economical choice.
2. Buy another Conn 7BW and thread the cup to accept screw rims. Then convert the original mouthpiece to a screw rim. This would allow you to use the same rim on both cups.
3. Thread the 7BW to accept screw rims and buy a new screw rim. (Our CH rim is very close to the Conn rim.) You would have a new rim and, if you wanted, you could buy a second identical rim so she won’t have to change rims when she changes instruments. Our rims are much more consistent than factory rims and our plating is more durable.
4. Thread the 7BW to accept screw rims and have her rim duplicated and use one or two copies on the horn and alto horn cups. If she is very sensitive to the rim contour and wants two rims this is the best option.
To give you an idea of the costs involved:
Thread a cup to accept screw rims or a rim to accept screw cups-$40
Conn mouthpiece-about $50
Osmun CH rim-$85 in gold, $75 in silver
Rim duplication-$75
If you need any more information please give me a call.
Bob Osmun
This entry was posted in Horn, Mouthpiece by Bob Osmun. Bookmark the permalink.

About Bob Osmun

We run a small music shop specializing in brass instruments, especially horns. We sell Engelbert Schmid, Finke, Hoyer and Alexander horns and have a world famous repair shop staffed by three of the best technicians in the trade. We regularly perform valve rebuilds, screw bell conversions and manufacture our own line of trumpet and horn mouthpieces. Jim Becker, our trumpet specialist builds custom trumpets and does all sorts of trumpet modifications.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s