TromboneChat

A couple of weeks ago, I picked up a medium bore Conn with F attachment that was labeled as a 79H. However, according to the serial number list on the Conn Loyalist site, my instrument (949xxx) is outside the production range.

At the same time, the stampings and lacquer on both parts look like they match, and the female tenon and slide are both stamped 78H. The slide does not have staggered cork barrels like a true 79H would. Thus, my left hand is cramped when holding it.

What, exactly, do I have here? Could it actually be a 78H Special that wasn't stamped as special? Did the 79H begin production earlier than 1966?

I have ideas to fix the holding issue, but that's a topic for the modification forum.

My 78 Special is marked as such. But I wouldn't be surprised if some weren't.

I have a 1962 78h special with f attachment, it is just marked 78h. All 78h’s with f attachment were special orders until 1966, when the 79h became a production model.
The earlier 78h specials had flat wraps, the 79h style wrap came out in the early 60’s. Maybe a couple of specials were marked as 79h earlier than that.

Original post updated with pics.

chromebone wrote: Sun Nov 16, 2025 4:53 pm I have a 1962 78h special with f attachment, it is just marked 78h. All 78h’s with f attachment were special orders until 1966, when the 79h became a production model.
The earlier 78h specials had flat wraps, the 79h style wrap came out in the early 60’s. Maybe a couple of specials were marked as 79h earlier than that.

Thanks, this is what I suspected to be true of my instrument.

If you match a 78h slide with a 79h bell section, the grip is very cramped 78 and 79 slides are not the same. The main brace for the 78h slide is closer to the player because the 79h hand position is further out {due to the trigger position} . I'd guess that you have a mismatched slide.

You could have a 78H that was modified with a valve section sometime later.

Thrawn22 wrote: Sun Nov 30, 2025 4:49 pm You could have a 78H that was modified with a valve section sometime later.

I don't think so unless it was factory... There doesn't seem to be any evidence of those specific flanges, ferrules and bell braces being removed/resoldered. Again, the lacquer looks largely original save for the main tuning slide and other areas that were clearly worked on (burned areas that weren't cleaned up).

Did known (early and late) 78H specials also have the staggered cork barrel setup like the production 79H? If not, why didn't Conn build them with the special order long trigger as seen on a handful of 88H instruments? That could have given the proper clearance. (Speaking of, short of going mechanical, this is actually the modification I'm seeking, including flipping the saddle. Long shot, I know...)

If only Conn included shop cards for factory special order instruments like Bach did...

My 78H Special also has two short cork barrels.