@Braintree fan. The step down transformer you used is for transforming the voltage from your source but it does not mitigate issues on fluctuations. The output of your transf. is dependent on what the input characterisitcs are which is taking from the raw power. In the event their is a drop or excess of voltage from the source (your socket outlet) your output also respond. That means your Onkyo will not be protected in such situation. My advise is buy an AVR (Automatic Voltage Regulator) that has an output of actual reading of 120V. Basically, the AVR you will see in the market are having 3x220 V + 1x110V. The TX-NR609 has a max. power consumption of 744VA. If you have other 120V appliances i.e. TV or blu-ray player you need to add those consumption to the 744VA. The new AVR now has spikes, sags and surge protections aside from the overvoltage & undervoltage protections. NOTE: when you size the AVR, the 110V legs is half of the capacity of the AVR. Let the store measure first the output voltage reading before you pay for it. If your source is 230V then you will get 115V output on the 110V socket. If you have 240V source which is excellent then you will get the 120V output which is healthy supply equivalent to your appliances. 115V to 118V is already tolerable, your 609 can handle it. You know the latest models now are computerized they have microprocessors and they are sensitive on the source you supplied to them unlike the previous ones. Here is the Computation example before you buy an AVR: 1. Onkyo TX-NR609 = 744VA 2. TV 120V say LED 55" = 228VA 3. Blu-ray Player = 14VA Total = 986 VA x 2 = 1972 VA You need to buy = 2500VA or 2000W. This rated capacity already considers the internal losses of the AVR. If your appliances is only for the 609, then you can adjust the capacity. Be carefull in buying the rating of the AVR, The VA is different from the Watts. When the storeman will tell you that it is 2500W do not believe on him. check if it is written in the AVR 2500VA, then the wattage cap. is only 2000W.
How I understand it, there are different units for different markets. The US/Canada sold units are 110v, while European and most other countries are rated 220/240v. I've purchased and imported from Amazon.com and saved around $400 by doing so. Now I've purchased a 1000W 220 -> 110v power transformer for $100 to use the receiver here in Australia and I'm still well ahead on the deal :o)
Cassaigne, I don't understand when you said "or both 110V and 220V and european plug" are you saying that the 609 sold here in the US is also available 110 and 220V, or this is available in european market?
Braintree, you purchased a step-down power transformer 1000W 220/110V? I would rather buy an AVR of 1500VA 220V input and the output for the socket outlets will be 4 x 120VAC IEC C13 female panel-mounted and I will replace the plug of the 609 with an IEC C14 which cannot be plugged to a 220V british or american sockets.
Thanks Mastercard. I'm not sure what an AVR is, as this is my first foray in using an appliance with a different voltage requirement to what we have here in Australia. I should correct my post by pointing out the step down transformer is actually for 240v>110v. The Onkyo TX-NR609 retails for A$1000+ here and our dollar is worth around 105 US cents. So despite the voltage inconvenience, I'm well ahead on the deal. I do wonder however as to what the idle power consumption of the transformer will be.
Thank you, your explanation is much appreciated. Here in Australia the voltage is rated at 240v as you say double the receivers 120v requirement. I think all power supplies can vary +/- 10v I understand that to be the case in the US where the local supply is rated at 120v.