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Step down transformers detrimental to SQ?

Hello, does anyone know if step down (or up) transformers have adverse effects on sound quality? I'm looking to pickup a 100V amp and use a step down here in US. 

Thanks
mrkoven
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cleeds
2,065 posts
 
millercarbon
Line voltage is nominal, as in uncalibrated, as in it varies. What is called 110 here in the US can turn out to measure lower ...
This is mistaken. Nominal voltage in the US is 120VAC and is regulated by state agencies, such as a Board of Public Utilities. Typically, a tolerance of ±5 percent is allowed.

I wouldn't recommend using any device designed for 100VAC on a 120VAC line.
georgehifi's avatar
georgehifi
4,966 posts
 
I heard some crazy Japanese audiophiles do double conversion, up and down, and claim it improves the sound.

Not quite but close, there is a bit of a fad at the moment over there, to use 1:1 isolation transformers, which are 100v in 100v out they are doubling up on these.
I’ve used a 2amp one now for 20 years now for my source equipment only, and will always do so.
https://www.servostabilizer.org.in/wp-content/uploads/2017/10/images1.png

https://www.servostabilizer.org.in/isolation-transformer/

here is a US made one, I’m sure there are others.
http://www.solar-emc.com/6220-1B.html

Here are some eBay ones.
https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2053587.m570.l1311.R1.TR12.TRC2.A0.H0.XIsolat...

Cheers George
glennewdick's avatar
glennewdick
702 posts
 

I ran a Luxman Class A amp 100v with a step down and found it wonderful. You do need a step down as the extra 10-20v in NA can cause issues.

 If you are concerned think of it this way there is a huge step down transformer out in front of your house or very close to it taking the 20'000ish VAC down to your house voltage so we all have a (many)transformer(s) in our circuit weather we want to admit it or not, well unless your running off batteries. Also there is always one inside your amp so another one really isn't a concern just make sure its big enough to handle turn on surge and power delivery.

Look on the back of your unit for power usage and triple it for a good measure. I ran a 1kw step down with my 50wpc Class A amp with no issues and room to spare.


interesting Georgehifi on the 1:1 that may be useful for DC blocking. DC on the line can cause transformer mechanical hum.

ericsch
180 posts
 
 @erik_squires 
  Excel Audio has 505's for $2,600

I ordered one last week, arriving today.
  
elizabeth
6,726 posts
 
Agree you DO need to use a step down transformer for a 100V AC device. As long as the transformer is rated well above the actual draw of the device it will work fine. Say the device draws 0.5 amps. If your step down is designed to handle 1.0 amps, or even better 2.0 amps.. your power will be strong.If you use a transformer rated for 0.2 amps.. then yeah you are gonna be starving the device and overheating the transformer!
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