I have a 16ohm tweeter and a 4 ohm bass/mid speaker wired into a crossover. I am assuming the amplifier will see 3.2ohms. Can

[Gimmehendrix]

Ok I own a leslie speaker which has a 16ohm tweeter and a 4 ohm bass/ mid range speaker.
The transistor amp is shot so I was thinking of driving the unit via a class D amp. I think the amp will see 3.2ohms at the crossover but I am unsure of whether the amp I have will drive that. The specs only quote 4ohms but since impedance varies considerably over the spectrum I am wondering whether this is a safe option.

 

[jsmithepa]

Yes.

Well most amps have a breaker circuit right.

 

[americanaudiophile]

The crossover will affect the impedance that the amp sees. It won't be the same as if the speakers were just hooked in parallel. You might be able to find the impedance if you google the make and model of the leslie speaker you have.
Class D amps (especially cheap ones) don't suffer difficult loads well. May not control the woofer well either.
If you have a multimeter you could try to measure the dc impedance of the speaker system at the input of the crossover. Not as accurate as measurements made a different frequencies but better than nothing.