My band had a cheese gig (read: we had to supply the PA) last weekend,
I got elected to setup (the other guys were busy in the afternoon).

I had a problem with the keyboard player's RAMSA PA speakers, it
turned out to be a loose crossover wire, but at first I thought the
Compression driver had blown in one of the cabinets. He had to replace
a diaphragm a while back so I kind of leaped to that conclusion.

Anyway, I pulled one of the horns out of the cabinet, rushed back to
my house, figuring I'll pull a pair of old EV 1824M's I had and slap
those on the RAMSA horns to get by for the gig.

So I pull the RAMSA driver off the horn, and low and behold, the EV
does not fit...it's too big.

I'm used to seeing three kinds of drivers, 1" thread on (which are
actually 1.4"), 1" bolt on and 2" bolt on (of course bolt ons come in
two, three, and four bolt patterns...just for fun I guess).

It appears that these RAMSAS use an actual 1" diameter horn throat (as
opposed to 1.4") ...has anybody ever heard of such a thing?

I was thinking of having him just buy some better drivers for the
RAMSAS but I don't see that actual 1" drivers are all that
commercially available.

Maybe I missed another format but these things are different from what
I have seen.

The thread pitch (38 TPI) looks about the same on the RAMSA Drivers as
the EV's, but the diameter is a good bit smaller.

Analogeezer