Donny good advice, I'm going to check the specs out b4 I plug that sucker in.

I found the specs on the PA-300/301 power supply, and it is rated 2.4-amps, NOT 4-amps. You may want to double check that power rating. The Hong Kong power supplies were rated to 3.5-amps, which is much heavier duty than Yamaha's power supply. Essentially, they are all just modified, laptop, computer power supplies. As for damaging the keyboard--not likely.

Gary

[This message has been edited by travlin'easy (edited 08-18-2010).]

I have understood that it doesn't hurt to go a little over, but not under. Is that right Gary ?

Expensive instrument and you want to risk major damage with a non recomended power supply voiding the warranty I might add...just to save a few bucks?........
I hope nothing happenes Steve.

[This message has been edited by Dnj (edited 08-18-2010).]

One of my pet peeves with Yamaha has always been their power supplies for their PSR series. At best, the power rating has been adequate if the volume is kept at reasonable levels. Go above the 3/4 mark and the power supply will overheat.

A good parity of this would be if you had a 50-HP engine in your car and in order to make the car reach 60 MPH you had to hold it to the floor. Yes, it will eventually get to 60, but in the process you'll fry the engine. Now, the same car with a 150 HP engine, which is three times more powerful, will reach 60 with little or no effort, and it can maintain that speed with 2/3 less effort than the 50 HP engine, thus the engine is under less stress and will last much longer.

In electronics, power supplies with a higher rating still supply the correct amount of power to the keyboard. However, it has the ability to supply more current (amperage) if required.

Could you damage the keyboard using a larger power supply? Of course you could, but not because of the power supply sending the wrong voltage or current to the keyboard. You could also damage the keyboard with Yamaha's power supply. Both, however, have overload protect circuitry, which usually (not always) prevents such problems from occurring.

I have a $13 Hong Kong power supply in my gig bag for a spare--just in case my Yamaha PA-300 would happen to fry. This has never happened to me, but it has happened to some members on this and other forums. All of my keyboards are out of warranty, therefore, I don't worry to much about using the Hong Kong supply as a spare. Whether Yamaha would frown on this for a keyboard that is still under warranty is a question Steve Demming would have to answer.

Good Luck,

Gary