using 230Volts Hifi components in the Usa

Yes, plenty of them.  You want a step-up transformer (120 to 240) though, not a step-down.

As a few have already said there are plenty of options for a step-up transformer. I bought a quality one many years ago when I moved to USA and it supplies the Amp, Tuner, CD player and the cassette deck. The system is still working as my second system in my painting studio with no trouble at all. 

Be certain your gear can function properly, at 60 Hz.

                                   Especially: the Cassette Deck’s motor.

Are you certain the motor is AC? I'd expect it to be more likely DC.

You can buy a  used US cassette deck mucho cheaper than a transformer.

The service drop into US homes is typ. 220vac single phase; 2 - 110~120 vac and a common ground from the pole. There’s the ’local’ ground, a bare copper line running to an earth ground nearby. That grounds the metal cabinet, and is a ’back-up’ if sh*t gos’ south.

The box inside has a ’left’ and ’right’ 110 leg, single phase, ’hot’.

Otherwise, some of the shop tools I own are running on magic.....

You can run your own line, but a step-up will be cheaper....

If you've only the single hot leg...

You ought to rewire.  Your wiring is likely 'knob and tube' if your home hasn't burnt down....yet....

Just sayin'

...and less exciting if you make a mistake... ;)