The LM1875 IC does that without any problem. Maplin even has (had ?) a kit of
parts
73
Andre' N4ICK
********************************
Peter Dodd wrote:

Hi Geri
> Does anyone of you have a proven scheme of a small linear PA available,
> that delivers about 2 or 3 Watts from 10 mW, preferably from 18 Volts
> (which is the voltage used by the exciter)? I am sure a small audio
> amplifier would do ...

I had a similar problem when I wanted to amplify the output of a
signal generator to drive my impedance matching unit. The amplifier
had to be linear to minimise harmonic content. I used a commercial
car stereo amplifier from a local radio junk shop (yes we are lucky
to still have one of these locally). See page 86-88 of 'The Low
Frequency Experimenter's Handbook'.

--
Regards, Peter, G3LDO

<[email protected]>