Notes on Operating a WT11 on Batteries
**Disclaimer** - try any of the below mentioned stuff at your own risk. I am only reporting tests on my WT11/WX11 synth, and will not be responsible for any self-inflicted damage to you or your synth....not to mention what your friends and family will think when you start buying parts at Radio Shack and play your wind synth in the car :-)
After a weekend of tests (and strange looks from my wife), I have determined that:
Your - actually, my Yamaha WT11/WX11 will safely run off 12 volts from a car battery, motorcycle battery, or similar battery pack. It can even run off of 8 D-batteries! Using regular rechargeable C or D-batteries, I have been able to run the WT11/WX11 for 3 hours. I have also been successful with just hard wiring to plain old 12V on the car, as well as the car lighter adapters that you can buy which have little voltage selector switches and multi-type plug adapters. The WT11/WX11 did NOT blow up when accidently wired in reverse.
The DC power connector which will fit your WT-11 is 5.0mm OD/2.1mm ID. The Radio Shack catalog number is 274-1567, and costs $1.69.
The Yamaha manual states that the WT11/WX11 unit draws 15V at 500mA, but measurements would indicate otherwise. Bench tests indicate it will run on as low as 7.5V before it acts wierd. No real audio problems at the wierd level, so my suspicion is that below 7.5v the logic circuits die when the 5v regulator cuts out. This makes electronic sense, but I won't bore you with that.
The bottom line on power draw is that it really consumes 3.5 Watts of power.
15V @~230mA, 12V @~300mA