Do step up transformers introduce sonic distortion into the amplifier?

[ThomasWolf]

I am looking to buy and import a headphone amplifier from the Japanese market into the U.S.

P-750u MARKII｜製品情報｜ラックスマン株式会社 - LUXMAN

www.luxman.co.jp

Will using a step up transformer(100v -> 120v) introduce any type of sonic noise/distortion/humm into the AMP?

 

[PENG]

I am looking to buy and import a headphone amplifier from the Japanese market into the U.S.

P-750u MARKII｜製品情報｜ラックスマン株式会社 - LUXMAN

www.luxman.co.jp

Will using a step up transformer(100v -> 120v) introduce any type of sonic noise/distortion/humm into the AMP?

Based on the following specs:

電源電圧	AC100V（50 / 60Hz）
消費電力	42W（電気用品安全法の規定による） 27W（無信号時）

You mostly likely can get one custom made but you will still have to find the right place and will likely cost more than you might expect. As an EE, I would be comfortable myself to use it without a transformer because I am sure a reputable brand like Luxman will not use a 100 V Tx not rated for much higher voltage and in terms of current, it should be almost the same. That's because while NA voltage is 20 % higher, current will end up about the same because of the 20% higher frequency. That would be just me, I am not going to suggest you run it without proper transformation.

Bottom line, contact Luxman technical support in writing, and ask them if you can just use it with 120 V/60 Hz safely and without voiding the warranty. That way if they say "yes" (that I expect they would) then you have it in writing. If they say "no" (that I doubt), ask them for suggestion.

 

[highfigh]

I am looking to buy and import a headphone amplifier from the Japanese market into the U.S.

P-750u MARKII｜製品情報｜ラックスマン株式会社 - LUXMAN

www.luxman.co.jp

Will using a step up transformer(100v -> 120v) introduce any type of sonic noise/distortion/humm into the AMP?

First, here's a link for those who don't read Japanese-

P-750u | HEADPHONE AMPLIFIERS | PRODUCTS | LUXMAN | Seeking higher sound quality

www.luxman.com

Second, the specs show that it uses 230V~(50Hz) / 115V~(60Hz).

You wouldn't be using a step up transformer, you would use a step down transformer because you want to supply it with lower line voltage and unless it has problems, you shouldn't hear any effect from it. You could also use a 'bucking' transformer.

 

[ThomasWolf]

First, here's a link for those who don't read Japanese-

P-750u | HEADPHONE AMPLIFIERS | PRODUCTS | LUXMAN | Seeking higher sound quality

www.luxman.com

Second, the specs show that it uses 230V~(50Hz) / 115V~(60Hz).

You wouldn't be using a step up transformer, you would use a step down transformer because you want to supply it with lower line voltage and unless it has problems, you shouldn't hear any effect from it. You could also use a 'bucking' transformer.

I've linked the Mark 2 version which is only available for the domestic Japanese market.

If you open the link via Chrome browser, it automatically translates the text into English.

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The power supply voltage for the mark 2 is;

Power-supply voltage	AC100V (50 / 60Hz)

 

[highfigh]

I've linked the Mark 2 version which is only available for the domestic Japanese market.

If you open the link via Chrome browser, it automatically translates the text into English.

The power supply voltage for the mark 2 is;

Power-supply voltage	AC100V (50 / 60Hz)

It only showed the Japanese version on my screen (with ), but had a Global Site button at the bottom.

Still, you need to decrease the voltage, not increase.

 

[PENG]

It only showed the Japanese version on my screen (with ), but had a Global Site button at the bottom.

Still, you need to decrease the voltage, not increase.

As I said, 100 V/50 Hz and 115 or 120 V/60 Hz are quite interchangeable in theory and in practice in general but he should contact the Luxman for the official word.

I have no idea why you think he needs to "decrease the voltage" if he is using it with 120 V according to his first post, presumably in the US.

 

[highfigh]

As I said, 100 V/50 Hz and 115 or 120 V/60 Hz are quite interchangeable in theory and in practice in general but he should contact the Luxman for the official word.

I have no idea why you think he needs to "decrease the voltage" if he is using it with 120 V according to his first post, presumably in the US.

If it was designed for Japan's 100VAC service, he wouldn't use a step-up transformer- that was my point. He would need to step down, if anything. Yes, it should be usable here but my point was about the application.

I bought a Chinese-made dust collector a while back and hope it doesn't work the way that did- I saw it work at the seller's shop, came home and wired it to the power in my garage (240VAC), using the same terminals he did. It worked for a while, made a strange noise, slowed and started smoking.

 

[PENG]

If it was designed for Japan's 100VAC service, he wouldn't use a step-up transformer- that was my point. He would need to step down, if anything. Yes, it should be usable here but my point was about the application.

I bought a Chinese-made dust collector a while back and hope it doesn't work the way that did- I saw it work at the seller's shop, came home and wired it to the power in my garage (240VAC), using the same terminals he did. It worked for a while, made a strange noise, slowed and started smoking.

Yes I agree with you on that, but my point was to check with the manufacturer first, because depending on the design, it may be okay without any conversion because while the voltage is higher in NA, the frequency is also higher, by the same %, so just reduce the voltage may, while it will work, have other effects, however minor.

It really depends on the design, again, ideally it is better to step down to 100 V as well as convert the frequency from 60 to 50 Hz, then we know there will be no performance penalty. As I alluded to, it will be tough to find a good quality voltage/frequency transformer/converter that will do the job without any negative effects. It may have to be custom made.

 

[PENG]

I bought a Chinese-made dust collector a while back and hope it doesn't work the way that did- I saw it work at the seller's shop, came home and wired it to the power in my garage (240VAC), using the same terminals he did. It worked for a while, made a strange noise, slowed and started smoking.

Case in point, that dust collector, depending on the type (such as induction, synchronous..), of the motor, may run with 20% overspeed because of the 20% higher frequency. So it might not have failed due to the 10% higher voltage alone.

 

[highfigh]

Case in point, that dust collector, depending on the type (such as induction, synchronous..), of the motor, may run with 20% overspeed because of the 20% higher frequency. So it might not have failed due to the 10% higher voltage alone.

220, 221, whatever it takes.