amplion: AR- 65; Senior Dragon - Amplion typology?

Dear fellow radiophiles,

does anyone of you know how the amplion type designations were created? Is there maybe one type number for the driver unit, and another one for the complete speaker?

I own a speaker that exactly matches the size and appearance of the above model (AR-65), but is labelled AU-2 on the driver. I wonder if it is an AR-65, or an AU-2, or if maybw the two models are the same.

Your help is appreciated,

Yours,

Nikolaus Loewe

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There are two types of drivers: the older circular metal type, and the later cloverleaf bakelite type.

up to 1925 I found only old type drivers. But the speakers are always a combination of horn style and a certain driver (choice of several resistances). All such combinations bear an individual number.
which embraces the horn and the driver impedance.
Same horn with different impedance driver has a different number. The same driver with a different horn has also an individual number.

The number defines a combination, and this number is noted at the drivers type plate! It does neither refer to the driver itself nor to the naked horn!

The driver is defined by its resistance, found at the type plate. Following values were available:
120 Ohms
2000 Ohms
250/1000 Ohms switchable
500/2000 Ohms switchable

To bring more complication into the matter: Amplion Gramophone Attachments are named AR66 (120 Ohms) and AR67 (2000 Ohms), but there is no associated horn
 

On later drivers of the cloverleaf style bakelite type I could not find any marking except "Made in Great Britain". My RS 1M is using such one where I am uncertain of its original combination.

Unfortunately the drivers and the horns can be haphazardly combined... Hard luck for the poor collectors!

 

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