I've used one experimentally with a high quality older tube tuner, because my line voltage runs somewhat high (124V). I noticed no difference sonically with and without the step-down transformer.
It could be a different story with your 100W/ch integrated amplifier, though, because its current demands are both much larger and fluctuating (with the music). On the other hand, it might actually improve the sound, because the transformer's limited bandwidth would filter out high frequency noise. Hopefully someone else who has used one with a power amp or integrated will comment.
I'd recommend a rating of at least 750W to power a 100W integrated. Here is one:
http://www.voltageconverters.com/itemdesc.asp?ic=VC750W.
Regards,
-- Al
It could be a different story with your 100W/ch integrated amplifier, though, because its current demands are both much larger and fluctuating (with the music). On the other hand, it might actually improve the sound, because the transformer's limited bandwidth would filter out high frequency noise. Hopefully someone else who has used one with a power amp or integrated will comment.
I'd recommend a rating of at least 750W to power a 100W integrated. Here is one:
http://www.voltageconverters.com/itemdesc.asp?ic=VC750W.
Regards,
-- Al