I purchased equipment from Japan, plugged it in and it blew up, can you help?

Of course, though the repairability of your equipment depends on what damage has been done.

Know Your Voltage

Different regions use different AC supply voltages. For example, Japan uses 100V, the USA uses 120V, and Europe and Asia use 220V, 230V or 240V, depending on the region. Anything other than 230V or 240V presents a big problem for people living in Australia where we have a 240/250V supply. Higher voltage AC supplies are better from a technical perspective which is great for us. More on that another time.

If you plug in a piece of electronic equipment that is set to run on 100V or 120V into a 240V socket here in Australia, IT WILL FAIL, without exception. Electronic equipment doesn’t “automatically adjust” as one enquirer who blew up his newly acquired equipment told me. He was probably thinking of equipment that uses switching power supplies or SMPS, like phone chargers, USB power supplies etc. Hi-fi equipment generally doesn’t use this type of power supply, unless it’s the cheap class D type gear which sometimes does.

Why Does Equipment Fail?

Good question. Transformers ‘transform’ AC voltages proportionally, according to the ratio of turns on their primary and secondary sides. For example, equipment set to run on 120VAC might contain a transformer that steps that voltage down to say 35VAC, which after rectification might be around 50VDC. What do you think happens when you feed that transformer 240V..? Double the input voltage equals double the output voltage and your 50VDC is now 100VDC. You can say goodbye to any electrical components that were rated at 50 – 60VDC. If your lucky, fuses might save the gear but in most cases the damage is more substantial.


Some hi-fi equipment can be set to run on a variety of line voltages, but much cannot. It often depends on the market the equipment was originally destined for and can vary among examples of the same model, dependent on production date and market. The adjustment may be external and quite straightforward or may involve work inside a chassis, including soldering unmarked jumpers into new positions in some cases.

Manufacturers have an array of models, years, markets and voltage reconfigurability. I’ve come to understand these relationships over the years, building up a database of information that assists me and my customers, but there remain many examples where voltage adjustability cannot be known until physically inspecting the equipment.

Equipment that is input voltage configurable is like gold as it can be used anywhere in the world without a step-up or step-down transformer and commands premium prices as a result.

Sensible Checks

Incredibly, I’ve seen locally supplied equipment set incorrectly. The Mark Levinson ML-7 preamp I recently repaired and a pair of Accuphase M-60 amplifiers are just two examples of gear that was set to run on 220V! Therefore, all equipment should be checked to ensure it is configured to run on the line voltage where it is to be used. This is especially important for equipment purchased outside its originally intended market.

If you know how to check and make the necessary changes, perfect. For most folks though, having this work done professionally is the best option. Note that, along with a change to line voltage, new fuses of the correct current rating will also be needed. Even if Johnny next door reckons he can do it for you, it might be wise to ask just how much Accuphase equipment he’s worked on.

But Mike, it will cost money to have my equipment checked and reconfigured.

Hmmm, yes it will. This of course must be balanced by the certainty that it will cost a lot more if newly acquired equipment is destroyed because these checks and changes weren’t made properly, or at all.

Russian Roulette

If playing Russian roulette with newly acquired hi-fi equipment in an attempt to save small change seems sensible, then I doubt anything I say will help. For everyone else, have your equipment inspected. Pre and post-purchase inspections have saved my customers thousands of dollars and are one of the best bang-per-buck decisions most people can make.

I hate to see equipment destroyed because of line voltage misconfiguration and yet I receive a steady stream of enquiries from people who have done it. This failure mode is completely avoidable simply by making a few sensible decisions.

If equipment cannot be reconfigured, a step-down transformer will be needed. General advice on this is available in the FAQ and more specific and detailed advice, as always, via our advisory service.

Scroll to Top