I’ll do my best!

We first need to establish what damage has been done and this can only be revealed by careful inspection.

Know Your Voltage

Different regions use different AC or ‘mains’ supply voltages. For example, Japan uses 100V, the USA uses 110/120V, 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. BUT – If you plug in a piece of electronic equipment set to run on 100V or 120V into a 240V socket here in Australia, IT WILL FAIL, unless a fuse saves it first.

Electronic equipment doesn’t “automatically adjust” as one enquirer who blew up his newly acquired equipment told me on the phone. He was probably thinking of equipment that uses switching power supplies or SMPS, like phone chargers, USB power supplies etc. Good hi-fi equipment doesn’t use this type of power supply.

The Problem

Transformers ‘transform’ or convert 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 this down to say 35VAC, which when rectified will be around 50VDC. When you feed that transformer 240V, double the input voltage equals double the output voltage. Your internal 50VDC supply is now magically a 100VDC supply, double what it’s supposed to be.

If this happens, you can say goodbye to any electrical components that were rated for 50VDC. If you are lucky, fast-acting fuses might save the equipment and I’ve seen this happen. In most cases though, the damage is more substantial, sometimes even terminal. It depends on the circuit, the voltage applied, and luck.

My recent (2024) repair of a gorgeous Pioneer PL-50L turntable is a great example of a 100V Japanese turntable failing when plugged into a 240V outlet. It’s also an example of careful technical repair work bringing about the resurrection of this beautiful piece. There were no internal fuses to save this deck. In the wrong hands, this repair would have been possible.

Configurability

Some hi-fi equipment can be set to run on a variety of line voltages. It 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.

Reconfiguration may be straightforward, or it may involve working inside a chassis, soldering unmarked jumpers into new positions in some cases and installing new parts. Some equipment cannot be reconfigured for other line voltages, most notably certain Japanese-only and North American-market equipment.

Manufacturers produce a variety of models/years/markets/voltage reconfigurability. I know many of these combinations and configurability but there are many cases where voltage reconfigurability cannot be known until an equipment inspection is conducted. Line voltage configurable equipment is like gold as it can be used anywhere in the world without a step-up or step-down transformer.

I’ve seen locally supplied equipment set incorrectly, many times. The Mark Levinson ML-7 preamp I repaired and a pair of Accuphase M-60 amplifiers are 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.

False Economy

We all want to save money but how many times have you tried but it ended up costing more? Equipment reconfiguration, service and repair are scenarios where you need to get it right. Trying to save money on something like this is like trying to save money on brain surgery. Do you want a barely capable, technically illiterate guy touching your expensive hi-fi gear or your brain? No.

Example: I recently (October 2024) heard about a guy with an expensive Accuphase SACD player, worth about $30K AUD. He cheaped out on the voltage conversion process and ended up with a $30K doorstop and then went on forums to find help, rather than ringing the right people.

I encourage everyone to carefully weigh up the pros and cons. For most owners, having this work done professionally is invariably the smartest and cheapest option. In addition to line voltage reconfiguration, new fuses of the correct current rating will be required.

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

Enquirer

Yes, exactly like it will cost money to have your car serviced and your teeth checked. It will, of course, cost a lot more if your equipment is destroyed in an attempt to save a small amount of money, but I have to leave this risk assessment to owners. That regret I hear when people call to discuss how their equipment died in the wrong hands is palpable. Sadly, these calls usually come too late.

Pre and post-purchase inspections have saved my customers thousands and are one of the most sensible things one can do with a newly purchased piece of equipment. We usually find things that need attention, which can often be leveraged into a price reduction/partial refund. It’s one of many benefits of engaging a specialist.

TLDR

I receive a steady stream of enquiries from people who’ve killed newly acquired imported hi-fi equipment with incorrect line voltage. This failure mode is completely avoidable by having your equipment assessed and reconfigured. If equipment cannot be reconfigured, a step-down transformer will be needed. More specific and detailed advice, as always, is available via our advisory service.