100-240v rated gear - universal power supply?

Taketheflame

Super Member
Hey all,

Just something I've been curious about lately. Every piece of audio gear I have is rated for the standard US voltage (120V). However, there are several vintage pieces of gear on my "wish list" that are quite hard to find versions of that are strictly US/North America voltage spec. However, I often find these pieces from worldwide sellers - many of them have multiple plug outlets on the rear panel, with a rated voltage range of 100-240v.

My question - does this mean I would be able to safely use gear like this on a US outlet by simply using the correct plug type/outlet/adapter? (i.e - no use of step up/down transformers).

Thanks!
 
- does this mean I would be able to safely use gear like this on a US outlet by simply using the correct plug type/outlet/adapter? (i.e - no use of step up/down transformers).
No..Step up or down transformers would be required if the piece did not have internal provisions to change mains voltage.ie transformer taps.
 
Ttf: Basically there are two types of such multi-voltage devices - the older type will typically make use of a transformer with multiple taps plus configration switch, the newer type will make use of a modern switched-mode power supply, nowadays most usually without a configration switch. Possible extra outlets on the back don't really have much to do with that. I.e., these will always provide just the same voltage that comes in via the power plug or jack.

Greetings from Munich!

Manfred / lini
 
all these mean is that if its plugged into 120, the sockets will supply 120. if the input
voltage is 240, then these sockets will supply 240.

however, everywhere I've been - anything other than 120 uses a different plug style,
British square pins, PR China V-angled square pins, etc.

check the schematic if in doubt.
 
However, I often find these pieces from worldwide sellers - many of them have multiple plug outlets on the rear panel, with a rated voltage range of 100-240v.

My question - does this mean I would be able to safely use gear like this on a US outlet by simply using the correct plug type/outlet/adapter? (i.e - no use of step up/down transformers).
Some modern -- typical digital -- gear will run on a wide voltage range without the voltage being switched. Most gear is specified for a relatively narrow range either around 120 volts, or around 240 volts. You can't simply plug 240 volt gear into a 120 volt outlet and have it work properly, even with an adapter. You need a power converter.

Take a look at the voltage input rating, which will almost invariably indicated the required voltage range.

If you're seeing power outlets -- i.e., plug sockets -- on the rear panel, the ratings of those should not be used as an indication as to the expected input voltage of the unit.
 
As someone who recently moved overseas, I went on a quest to find and only bring dual voltage gear. As DaveVoorhis said, look at the back panel or on the power supply (if it's external) to see what it says for input voltage. I've got a mix of things, some have a switch you have to flip (and sometimes they have different fuse rating recommendations), some automatically sense the voltage. The newer digital gear just does its own thing, but the Parasound Zamp and Ztuner, my Audioengine S8, and a few other pieces I brought needed to be switched manually.

To sum up, if the gear you've found says that it can take the full range of input voltage, you're likely in business. Assuming it's vintage gear, find the switch that controls input voltage. Good luck!
 
If the published rating is 100v-240v, it has switching power supply and will run anywhere between those two voltages. If it has two ratings of 120v and 240v, then some conversion has to be done to run it safely. Could be a switch or an internal jumper that needs to be changed.
 
If the published rating is 100v-240v, it has switching power supply and will run anywhere between those two voltages. If it has two ratings of 120v and 240v, then some conversion has to be done to run it safely. Could be a switch or an internal jumper that needs to be changed.
So, if it says this right above where the power cord connects to the chassis...

AC
110-240V (listed as a range, not something like 120/240 V)
50-60Hz

It can be used without a conversion transformer? Was it common for vintage gear to have listings like this?
 
So, if it says this right above where the power cord connects to the chassis...

AC
110-240V (listed as a range, not something like 120/240 V)
50-60Hz

It can be used without a conversion transformer? Was it common for vintage gear to have listings like this?
Not, not common for any vintage gear to have this. Switching supplies in consumer equipment has only become popular in the last ten years or so. And yes, it can be used without a conversion (step-up or step-down) transformer. My company makes consumer PA gear and we use universal power supplies like this often.
 
So, if it says this right above where the power cord connects to the chassis...

AC
110-240V (listed as a range, not something like 120/240 V)
50-60Hz

It can be used without a conversion transformer?
Yes.
Was it common for vintage gear to have listings like this?
That perhaps depends on your definition of "vintage", but it would be very unusual, if found at all, in analog gear made before (roughly) the mid-2000's and it's unusual in the majority of purely-analog gear made today.

What is the device that has this rating?

Unless... Are you referring to a mechanical switch that lets you select a variety of voltages between 100 and 240?

That's not unusual on vintage gear.
 
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A fair number of vintage receivers and amps have multi-voltage transformers. I have seen lots of Pioneer and Sansui gear like that, and some Marantz.
 
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