# Isolation transformer - am I imagining things or does this actually work?



## Timestretch

I recently bought a Tripp Lite IS250 250W Isolation Transformer, to add into my system, which is as follows: 
PC -> optical cable -> DAC1 -> Lyr -> (headphone out) HE-6; (rear rca out) KRK subwoofer -> KRK rokit 8 monitors  
   
Before adding the Tripp Lite, I had a very noticeable noise floor in my KRK speakers even with no audio playing. 
   
I added the tripp lite, plugging only the DAC1 and Lyr into it; leaving the speakers and computer all still on surge protector / power strips on the wall outlet.  
   
Since adding the tripp lite, the KRKs are dead silent, no noise floor at all. I suppose the Lyr, being a powerful and very sensitive amplifier, was not doing too well with "unclean" power or some voodoo thing that I don't understand, and the Tripp Lite fixed that issue and the Lyr is getting "clean" stuff now and not putting out a noise floor to the KRKs. I do live in a 70s apartment, so maybe the power from the wall is pretty "crappy."  
   
*That I can accept, but what about this*:
   
I previously did not notice much of a noise floor listening to music through my HE-6 headphones -- these come straight out of the front of the Lyr, unlike the KRKs which are plugged into different things and have power supplies of their own, etc, etc. However -- and this is where I think I am probably imagining things --  I feel like my headphones are clearer now than they were before, now that the Lyr/DAC1 are lugged into the isolation transformer and not a plain surge protector.  It is as though tings are cleaner - if there was any static background noise in the headphones before, it is further reduced now, I just can't be sure of it because it seems subtle or something. Well - subtle -- that's the thing, I haven't done a scientific back and forth blind test yet, but it seemed like a big difference to me, I "noticed" the new clarity (or imagined it, your choice) right away as soon as I first tried the headphones after installing the isolation transformer.
   
Any thoughts? 
   
  edit:
  Also, I might add that this transformer is extremely, extremely heavy for it's size. It's like a solid brick of iron or something. It is very cool and I like it. And, though the amazon.com image was of a white metal box; mine is sleek black.


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## DaveBSC

Quote: 





timestretch said:


> Also, I might add that this transformer is extremely, extremely heavy for it's size. It's like a solid brick of iron or something.


 

 Pretty much. Properly designed power conditioning works. There are a lot of ways to go about that, but an isolation transformer is one of the most affordable. The idea that component power supplies are "immune" to noisy AC power is a fallacy, one that's often repeated around here.


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## WNBC

I can believe it.  I have the same isolation transformer.  After months of no noise with the Lyr I had some AC noise that could be heard in my headphones and when I used the Lyr as a pre-amp.  Without the Lyr connected I was still hearing noise in my active speakers so it wasn't the Lyr or tubes as the culprit.  I couldn't just move my rig to another room.  I tried the Tripp Lite and it did the trick.  My new place doesn't quite suffer the same noise issue but I keep the isolation transformer in place.
   
  Would be curious to know if there are even better ones than the Tripp Lite or brand doesn't matter, they all do a good job at eliminating noise.


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## DaveBSC

Quote: 





wnbc said:


> Would be curious to know if there are even better ones than the Tripp Lite or brand doesn't matter, they all do a good job at eliminating noise.


 
   
  Spending more will buy you much larger transformers that can handle a full 20A, 2400W circuit. The transformers in these units are also of higher quality, and are balanced to reject common mode noise. You also get more and better outlets, and passive noise suppression by way of shielding and capacitors.


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## WNBC

Holy cow. That's not a transformer that's a tumor. 
Who else makes quality isolation transformers? 
The Tripp Lite isolation transformers are the first ones to come up in google searches.
I'm assuming the circuitry of the isolation transformers is different than power conditioners.
Or are isolation transformers essentially non-sexy power conditioners?


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## DaveBSC

Quote: 





wnbc said:


> Holy cow. That's not a transformer that's a tumor.
> Who else makes quality isolation transformers?
> The Tripp Lite isolation transformers are the first ones to come up in google searches.
> I'm assuming the circuitry of the isolation transformers is different than power conditioners.
> Or are isolation transformers essentially non-sexy power conditioners?


 
   
  B-P-T, Equi=Tech, Silver Circle, Furman, ExactPower. The Running Springs conditioners use a combination of transformers and inductors. It's all power conditioning, using a transformer is just one way to do it. They've been around longer than other types and are very well understood. As long as the transformer is much bigger than the draw of the equipment attached, current isn't an issue. The downside is weight, and the fact that they can hum if there's DC on the line. Capacitor based conditioners like Audience units can deal with the same current demands with a fraction of the weight, and they won't hum. Really good caps cost a lot of money though, and the Adept Response Teflon units don't come cheap.


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## obobskivich

davebsc said:


> Pretty much. Properly designed power conditioning works. There are a lot of ways to go about that, but an isolation transformer is one of the most affordable. The idea that component power supplies are "immune" to noisy AC power is a fallacy, one that's often repeated around here.




Pretty much have to agree. I used a similar TrippLite unit (it was a full CVT/iso though) - there's an improvement with some things, but the transformer hum (which is probably just my unit, or the CVT function - I've seen it argued both ways) was annoying when everything was off. But yeah, absolute noise immunity is not always guaranteed (some components are better than others at rejecting noise, sure). ATM I just have a power bar that has RF noise filtering, but no xformer; it does a good enough job imho. And like Dave said otherwise - the bigger, heavier units are just buying you capacity, not really quality (I'm sure at some point you gain some quality or flexibility (if you go all the way up to a VARIAC or something like that, you can pick what your AC output voltage is and it just abstracts things that much further), but going up the TrippLite line for example, is just adding current carrying). 

Another brand I'd look at beyond TrippLite would be APC. I've heard some good things about PS Audio as well. This is in addition to what Dave suggested (like Furman). Most of the Monster Power products are *extremely* basic for what you're paying (this is where "power conditioning" is really bastardized), until you get up to the big units (that cost a whole bunch) which introduce CVT and other regulation, and while they can usually handle 10-15A, if you don't need that much current, why pay that much? The screens are fun to watch, but that's about it.


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## WNBC

Thank you all for the additional info here.  I think if I went up the Tripp Lite chain there is a hospital grade isolation transformer (250-1000 watts) and then this UPS/isolation transformer thing is intriguing but probably overkill...
http://www.amazon.com/gp/product/B00006B826/ref=ox_sc_act_title_3?ie=UTF8&m=ATVPDKIKX0DER
   
  At the new place I haven't detected as much AC noise so I'm fine with my 250W Tripplite isolation transformer.  
   
  How did you all learn about power conditioning?  Backgrounds in electrical engineering?  For us layman, maybe one way to go about researching and learning about these products is to find the white papers on some of the high end models and see what is inside the good ones.  To be honest, some of the brands like Running Springs have conditioners in the thousands.  More than my gear costs in itself.  I see myself as someone in the APC and Furman budget range.  With headphone rigs do we need more than a couple hundred watts carrying capacity?  What would be nice is the voltage regulation in power conditioners.


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## obobskivich

I don't know much about what goes into making a device "medical grade" aside from a degree of FDA testing/certification. My understanding is that it has more to do with the FDA slapping a logo on the device so that if some catastrophe happens and someone dies, the hospital or manufacturer cannot be sued because of equipment fault since they can go back and say "the FDA said this thing met whatever standard that the FDA created for whatever this thing is, and we did what the user's manual said!" I don't think it correlates to higher performance, at least explicitly. I may be mistaken though. 

As far as "how did you learn about power conditioning" - experience, trial and error, I've done some FOH stuff over the years and been exposed to a lot of Furman gear. Done some IT stuff and been around APC and TrippLite for ages and ages. Finally took one home and hooked it up; it's an ancient bugger, but it performs. 

Onto to the tech stuff - no you should not need more than 100W (around 1A) carrying unless you're driving something other than a headphone amp, DAC, etc - like if you wanted to plug your PC into it. I probably wouldn't plug your PC into an iso transformer or CVT though, just because of how much capacity it'll require, and because you can get some seriously nice PSUs that will handle some seriously screwed up AC inputs. They do make CVTs that can carry PCs though - they're a lot more expensive (again, capacity costs). 

As far as CVTs - TrippLite makes a few, they don't cost a lot more than the ISOlators, and they include the ISOBAR pack. Stand-alone "power conditioners" are a lot harder to look at; some of them (like the ones Dave mentioned) actually do something, some of them are just *really* expensive power taps. 

See this:
http://www.tripplite.com/en/products/model.cfm?txtSeriesID=838&txtModelID=208

Of course you can get ritzier, but it's an example.

APC has some stuff that's designed to look less industrial:
http://www.apc.com/products/apcav/index.cfm


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## DaveBSC

Quote: 





wnbc said:


> How did you all learn about power conditioning?  Backgrounds in electrical engineering?  For us layman, maybe one way to go about researching and learning about these products is to find the white papers on some of the high end models and see what is inside the good ones.  To be honest, some of the brands like Running Springs have conditioners in the thousands.  More than my gear costs in itself.  I see myself as someone in the APC and Furman budget range.  With headphone rigs do we need more than a couple hundred watts carrying capacity?  What would be nice is the voltage regulation in power conditioners.


 
   
  I've owned many of them, and read tons of reviews. I'm currently using a B-P-T BP-1. I really like their stuff, they are no nonsense, and their prices are reasonable.


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## obobskivich

davebsc said:


> I've owned many of them, and read tons of reviews. I'm currently using a B-P-T BP-1. I really like their stuff, they are no nonsense, and their prices are reasonable.




Dave, you should qualify that you're a billionaire playboy when talking about prices. 

And I mean that in a jesting and good way.


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## Happy Camper

I use a medical grade iso. transformer with hospital receptacles only because it was taken out of service with an old x-ray unit and I happened by the bio-med shop at the right time. 

They make a difference in background noise to both the amp and source. I use mine with my sources and a good power cord from the wall to the amp(s). Unless the source material is terrible, there is nothing to hear, perfectly still. That's as much a priority as the sound IMO for critical listening.


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## DaveBSC

Quote: 





obobskivich said:


> Dave, you should qualify that you're a billionaire playboy when talking about prices.
> 
> 
> 
> ...


 

 I really do think B-P-T's pricing is very reasonable. Chris is up front about what goes in his products, and if you want to see for yourself, all it takes is a few screws. There's no attempt to hide anything, no "mystery" boxes. If you don't want to pay for fancy front panels, you don't have to. He offers all of the latest TOTL outlets and fancy wiring, Bybee and V-Cap parts and all the rest, but again, you don't have to pay for any of that if you don't want it. Compared to what Equi=Tech and Silver Circle charge for the same size transformer, the BP-3.5 is something of a bargain. Even the Furman IT-Reference 20i is WAY more expensive, and it's not as good.
   
  At the $500 level he offers the CPC, which is comparable to the Majik BUSS and better than just about anything else at that price point. Most of the products below $500 either don't do anything, or make the sound worse than straight from the wall.


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## obobskivich

davebsc said:


> I really do think B-P-T's pricing is very reasonable. Chris is up front about what goes in his products, and if you want to see for yourself, all it takes is a few screws. There's no attempt to hide anything, no "mystery" boxes. If you don't want to pay for fancy front panels, you don't have to. He offers all of the latest TOTL outlets and fancy wiring, Bybee and V-Cap parts and all the rest, but again, you don't have to pay for any of that if you don't want it. Compared to what Equi=Tech and Silver Circle charge for the same size transformer, the BP-3.5 is something of a bargain. Even the Furman IT-Reference 20i is WAY more expensive, and it's not as good.
> 
> At the $500 level he offers the CPC, which is comparable to the Majik BUSS and better than just about anything else at that price point. Most of the products below $500 either don't do anything, or make the sound worse than straight from the wall.




I don't doubt it. I'll actually have to give B-P-T a looking at at some point in the future myself.


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