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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
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!
atmasphere's avatar
atmasphere
7,068 posts
 
Its also possible to step down the AC voltage by doing an old DIYer trick which is to buck the AC line voltage.

This is done with a smaller transformer that has a secondary rated for the current you need (50% more than the fuse rating is good) and the difference in voltage. Since most homes are at 120Volts these days, that's a transformer with a 20Volt output at however many amps your amp needs.
The primary of the transformer runs off of regular wall voltage. The secondary is put in series with the AC line going to the amp. You have to try the secondary hookup both ways- one way will buck the voltage up 20 volts (adds to the line voltage) the other way will subtract 20 volts which is what you want.

The result is a much smaller and less expensive transformer can be used but you have to know more about how to use it. There are always tradeoffs...
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