Is there a problem with connecting a keyboard that is designed for use in Europe (AC 230) and connected in current in America that is AC 120? If so, how do you change the setting in the keyboard, if there is one?

certainly is a problem. The primary of the mains transformer needs a half tap. On older machines there was a switch on the back for the 2 voltages, but this was blanked off on the 7k. You can buy an external mains converter transformer and would need around 100W and over. Or open it up, trace the mains input, check with a meter etc, hope that the tap is on your transformer.

Thanks, very much technicsplayer. As always, you come to the rescue. Since I don't know a light bulb from a socket, it sounds complicated. Do you think a regular TV or music repair shop could do this? The KN7 is so hightech, I am somewhat apprehensive.

you're welcome a good tech could sort out the transformer IF it had a suitable tap to use pretty easily, but opening the case etc without service manual may be a bit risky if not in that particular line of work. I would certainly go for an external transformer or inverter wall plug, which will probably work out much cheaper than the labour would anyway.

Hi Alec,

When you refer to an "inverter wall plug," are you talking about what is sometimes called a wall wart? I have had to use them on occasion, especially on reverb units. They usually are about 9 volts. Is this big enough?

that is a dc supply, different animal, but you can get electronic converters that look similar and plug into your US walls and have a euro socket on the front for 220 or 240V appliances OR a transformer in a box with flying lead to plug.
A quick google and this is the first to come up: http://www.dcacpowerinverters.com/itemdesc.asp?CartId=EVEREST{493094CF-24FD-46A6-B4F3-D58C6689854A}&ic=VC100W
14 $ for the 100W should be ok for continuous use, or 20 $ for the 200W gives a bigger safety margin.
Ebay has some electronic converters very cheap occasionally but I have no knowledge of their reliability or production design competence, so a few extra $ for a brand name with warrantee is probably wise for your precious 7k.

Just to assure you that an external transfer works OK.I come from the UK and I temporarily went out to USA to live 5 years ago with a KN1500 240v UK keyboard which I used via a transformer(240v stepped down to 120v - 100w) until I purchased a KN7000 3 years later.
When I returned to UK I used the same transformer but the other way around (120v stepped up to 240v intake. I originally bought the transformer at Fry's and they have an internet shop - Outpost.com (Heavy item so postage could be expensive)I have never had any problems with my external "black box".
When I returned to UK to live, I did enquire about having the internal transformer changed and I would have been charged about 100 dollars for the part, plus a labour charge. However I stay with the premise "if it works Don't fix it" so I have left it as it is.

Thanks, Alec -

I brought up the site. Gee, these things weigh close to 5 pounds and are about 4 inches square! They are quite sizable compared to a 9 volt wall wart.

Do you think that there could be a switch inside the keyboard instead of it being on the outside? Maybe Technics felt it safer to do so.

Thanks, UKTexan -

I guess that answers my question on a switch inside. If there were one, you wouldn't have been given a $100. charge to change it.

yes, that link is a transformer, you can also get electronic converters without a heavy transformer: http://cgi.ebay.co.uk/NEW-110-TO-220-VOL...1QQcmdZViewItem
this is only 50W so a slightly higher spec would really be needed, and with all the warnings about this sort of product I mentioned earlier, but serves as an example of the alternative type.