Tannoy type speakers can often be tapped. In other words they usually have a variety of selectable wattage outputs which are set with a small flat blade screwdriver on the back of the horn (I assume you mean horns). They often work on the 100Volt line principle, which allows long runs from the amp and between speakers without too much loss of signal strength
You simply put the screwdriver in the slot and turn it till the slot matches up to a diagram printed on the back.
Small horns may have a selection of 5Watts, 15Watts or 30 Watts.
It is important that the total wattage of all of the horns does not exceed the output wattage of the amplifier. This is calculated by adding up the wattage of all of the speakers on one line. I'E 10 x speakers set at 30W = 300W
The speaker type cabinets and ceiling speakers are varied usually by looking at the transformer inside and a wire can be placed on different pins on the transformer to change the output wattage. The outputs are marked on the transformer. Again the max output of the amp must not be exceeded.
If this is not viable. You can buy a zone amp which can run a number of different lines with speakers on (Imagine a normal amp but with 8 speaker channels for instance) Each channel has a separate volume, bass and treble control. Each channel can be run out to separate areas and in combination with wattage selection on the speakers themselves allows for a quite controllable setup.