Tripp Lite IS250 Review (Isolation Transformer)

[DWI]

There are all sorts of isolation and the manual seems clear.

Seems popular with AV users, which is what I'm looking at, as I currently use a $10 mains block with 5 devices connected. This Amazon 5-star review gives one of many similar examples and makes the point about unbalanced signals only.

 

[theREALdotnet]

Anyway, there are indeed reasons this could be useful, though I agree they aren’t audio reasons for almost all practical applications.

I bought one to defeat the DC offset induced transformer hum in a class-AB amp I used to have. It reduced the transformer hum, unfortunately, the iso-trans was humming louder than the amp ever did

I’m now using it with my oscilloscope, so I don’t have to think twice every time I put a probe to a mains powered, safety-earthed device…

 

[Count Arthur]

Why would anyone buy this, thinking it will improve the sound? It's like buying a golden spoon and thinking your soup will taste better.

It's funny you should say that, and this is totally off topic, but I was listening to a radio show a short while ago where some chefs and food critics were having a discussion and one of them mentioned the effect that cutlery made from different metals had on the flavour of food.

Apparently silver cutlery is really bad, stainless steel is fine and gold is best - who knew.

Anyway - as you were.

 

[Dennis_FL]

I got this to clean up some ac noise in my audio setup with turntable.

I had a low decibel hum and for months tried to track it down. I put my ear up to the speakers, the subwoofer, the amp, the "power center" and nothing. I was always moving wires around as I thought I was picking up mains hum somewhere. I tried everything and then I found it. It was ac noise all right. It was my neighbors ac. His air conditioner. The hum is still there. Drives me crazy.

My heat pump is closer but I can't hear it.

 

[restorer-john]

It is clear that neither you nor PMA have any idea of who buys these to tweak their audio systems and confusing them with others used for safety reasons on a workbench.

Who buys them is absolutely irrelevant, Amir. Quoting Amazon reviews now are we? What's next? Wikipedia? I mean, come on, I know you can do better.

You are besmirching another mains related product that makes absolutely no claims other than these, (from the company's data sheet):

What specific issues do you have with any of the claims in TrippLite's product information sheet as listed above? Where exactly did they falsely advertise or misrepresent their product?

This ongoing pattern of attacking perfectly valid products, designed for specific purposes has to stop. It really must.

 

[Count Arthur]

I bought one to defeat the DC offset induced transformer hum in a class-AB amp I used to have. It reduced the transformer hum, unfortunately, the iso-trans was humming louder than the amp ever did

I’m now using it with my oscilloscope, so I don’t have to think twice every time I put a probe to a mains powered, safety-earthed device…

I had a pair of mono amps that had fairly large, ~800VA, toroidal transformers. These were noisy, there was no noise from the speakers, but a buzzing from the amps themselves. One was worse than the other and the noise would be better or worse at different times.

I used a DC blocker I got here: https://www.atlhifi.com/product-tag/dc-filter/ and it was very effective, the amps were completely silent when connected to the DC blocker.

There was another thread about it: https://www.audiosciencereview.com/...-dc-blocker-to-help-stop-transformer-hum.948/

 

[Lambda]

And you would get UL certification how?

the same way this device dose

(i think they yust don't)
but putting 4 diodes in the ground part is relatively save.
Especially behind a low power fused transformer

But again your missing the point..

You showed multiple times Mains power Quality in therms of distortion has as little to now measurable impact on output audio qulety in your test setup.
Yet you use same test again an focus on measuring mains distortion and so on.

The isolation Transformer provides Common mode isolation.
But you don’t test for this.

the isolation transformer can reduce leakage currents to main that would otherwise introduce hum.

 

[AndreaT]

R.I.P. for the Isolation Transformer. Thank you Amir!

 

[theREALdotnet]

I used a DC blocker I got here: https://www.atlhifi.com/product-tag/dc-filter/ and it was very effective, the amps were completely silent when connected to the DC

Yep, I made a DC blocker, too, after the iso-trans disappointment. I sold the amp a short time later, so the DC blocker never made it past the project board stage…

 

[JSmith]

Regardless of the marketing not being directed at audio related purposes, it sure is discussed around the place as an audio related product;

Tripp Lite IS250 Isolation Transformer 250W Surge 120V 2 Outlet 6 feet Cord TAA GSA

Can some one roll me what benefit this will do for my system? I now have a basic power strip with a on/off switch and a very short power cord. This one only has two outputs so what would be the best to use it for, MacBook, external HD or pre amp, or Power amp. With using it I would need to use on...

audiophilestyle.com

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

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...

www.head-fi.org

JSmith

 

[Lambda]

turntable. Didn't do much."

It is clear that neither you nor PMA have any idea of who buys these to tweak their audio systems and confusing them with others used for safety reasons on a workbench.

So all turntables have 3 Prong plugs with mains earth?!

I think not... turntable is actually a good example of an device hat can benefit from lower mains leakage
(can != must. and only if used right.)

If you try to "debunk" or test fixes for problems i would say you first need to recreate the problem.
Without a problem how can you test a potential solution?

Its like testing medicine on someone healthy. if it is not making a already healthy person feel better how can it help sick person.

 

[restorer-john]

Regardless of the marketing not being directed at audio related purposes, it sure is discussed around the place as an audio related product;

Bottom line is the TrippLite is not being marketed as such. What deluded people do with products is hardly the responsibility of an individual to 'expose' or protect them from, is it? It is not up to Amir to 'save' a bunch of misguided audiophools from their own ignorance or misguided stupidity, is it? What ever happened to critical thinking?

Company reputations are being damaged (and may incure financial losses) by incorrect testing methodology, incorrect assumptions and/or blatant ignorance as to the functionality of the devices being tested.

 

[restorer-john]

So all turntables have 3 Prong plugs with mains earth?!

I think not... turntable is actually a good example of an device hat can benefit from lower mains leakage

Absolutely.

Many turntables are earthed and many are not. Some are chassis earthed, mulitple point, others are double insulated with no exposed metal earth point that is related to mains earth. Some will gnd/earth the plinth/motor/arm bearing and headshell/cartridge collet, others will float the cart. Some carts have an earth strap, others have none, or it can be removed.

Some have a separate gnd/earth wire, others have none. Many benefit from judicious earthing and/or cart/arm earthing practices. (I'm looking at you Grado).

Sometimes, it takes a product like this to solve all the turntable ground loop woes.

 

[SIY]

Apparently silver cutlery is really bad, stainless steel is fine and gold is best - who knew.

And there's good chemical reasons for that. Nothing mysterious.

 

[DudleyDuoflush]

If I wanted to buy one of these for a safety or specific isolation issue I would not be interested in Amir's review.

If I wanted to see the general impact it would have on the quality of my audio system I very much would so thank you for the review.

 

[Lambda]

Since unbalanced audio gear almost always connects signal ground and chassis/safety grounds together, this box provides no isolation at all, or any cure for mains/ground loops.

Hifi gear even having safety grounds is a relatively recent thing/trend
I have/had many Amplifier, caste tape decs, CD player and turntable with only 2 pin plugs.

So in this case yes a isolation transformer can help lower mains leakage and captive coupled ground loops trough mains and/or neutral.
this is especially noticeable with low power signal sources like turntables and not noticeable with high power signal sources like DACs.

Oh and that the AP Analyzer input is maybe better in dealing with common mode current/noses then the average Phone preamp/AVR
shuld also go without mentioning.

Even if it would be like you say that only balanced gear has it’s signal ground not directly safety ground referenced...
Many users use speakers/amps with balanced inputs but with unbalanced cables/sources.

If I wanted to see the general impact it would have on the quality of my audio system I very much would so thank you for the review.

They are not used/marketed as universal improvement but as a fix for a specific problem.
in the audio world this would be common mod currents and "hum".

You don’t take pain killers if you have no pain and expat to feel better.
(Well maybe that's a bad example considering Opioid abuse... but you get the point)

 

[5th element]

If I wanted to buy one of these for a safety or specific isolation issue I would not be interested in Amir's review.

If I wanted to see the general impact it would have on the quality of my audio system I very much would so thank you for the review.

You don't need a review of an isolation transformer for that though. It's obvious that the mains quality out of it is going to be worse than what goes in. Luckily we know well designed electronics don't give a fig about the quality of the mains they are fed.

If you need the basic functionality of what an isolation transformer provides then you need to use one. You also don't need a review for this.

 

[DWI]

The isolation Transformer provides Common mode isolation.
But you don’t test for this.

... which it says in the manual.

There are good and bad power products, but they all tend to work as a system and certainly my audio power is part of an overall installation from the incoming 3-phase supply and how the rest of the house is wired. The main issues are isolation of electrical devices, voltage stability, impedance and probably to a lesser extent noise (which is quite easy to deal with). Testing individual products for noise seems a little off the mark.

Frankly, you can hear if you have a problem, and with AV you can see it. More to the point, most people probably only look at these products if they have a problem and need a fix, the results seem very system-dependent and my approach is to buy from Amazon, as you can always return it, or a dealer with a good return policy.

I've experienced unexpected benefits from power products when I thought everything was just fine, and I've removed power products that were beneficial with certain components when that component was sold. It makes it difficult for the marketing boys because if they drafted copy saying "this component may work, depending on your system", they'd probably be looking for another job. This is more of an industrial product and the product manual is quite clear.

 

[DudleyDuoflush]

Hifi gear even having safety grounds is a relatively recent thing/trend
I have/had many Amplifier, caste tape decs, CD player and turntable with only 2 pin plugs.

So in this case yes a isolation transformer can help lower mains leakage and captive coupled ground loops trough mains and/or neutral.

Even if it would be like you say that only balanced gear has it’s signal ground not directly safety ground referenced...
Many users use speakers/amps with balanced inputs but with unbalanced cables/sources.



They are not used/marketed as universal improvement but as a fix for a specific problem.
in the audio world this would be common mod currents and "hum".

You don’t take pain killers if you have no pain and expat to feel better.
(Well maybe that's a bad example considering Opioid abuse... but you get the point)

Therefore the usage would fall under a specific isolation issue.

 

[maty]

Tripp Lite IS250

Amazon

Amazon.com

Resized and optimized