EquiTech 1.5RQ Balanced Power Review

[wwenze]

The operating principle of a MOV is not sacrificial.

It's only when it heats up too much then it starts spoiling.

 

[martijn86]

So, if we want to protect our equipment and feed it good AC power, what exactly should we be buying?

I'm looking at Furman products but am at a loss as to which one(s) would represent prudent investment in protection (and if feasible reproduction quality).

A fused power brick? Or if you worry about power cuts, an uninterruptible power supply (UPS) that deals with voltage spikes? I mean your mains power IS good power.

 

[amirm]

Try measuring this balanced power with DAC and preamplifier.

This is a high power unit designed to drive amplifiers and such as I quoted in the intro.

 

[amirm]

Is the measurement of the AC signal done without load? What happens if we add an amp drawing 200W?

The original AC mains is under load. It is being used by Audio Precision and my computer workstation.

On the 200 watt thing, what difference does that make when the output of the amplifier degraded???

 

[Francis Vaughan]

I think there is a lot more here than is being covered.
Looking at the manufacturer's site there is a lot of information, and a lot of it actually makes sense. However the sale of these devices for domestic use is not something that makes any sense. As Amir notes, a balanced mains feed does not meet code in the US for domestic use. The manufacturer has an FAQ that quotes the code, and is quite clear about this. However, their web site has two parts, one for commercial use, where this FAQ can be found, and a domestic side for AV applications, where nothing is mentioned about domestic use being a violation.

So, what is the device's real use case, and is it reasonable?
The device is sold for use in professional sound recording applications, and its use case is simple. It entire job is to help manage grounding issues. No claim is made about magic clean power. Everything is directed at building an installation where common grounding problems can be eliminated. This isn't a trivial installation, and is well beyond any domestic application. Amir's tests exactly match what is expected of the device. No snake-oil or woo. But in domestic settings the device has no role, and marketing it into one is both a violation of safety codes, and won't do anything that the device is intended to help.

The entire idea is to allow the creation of an isolated power run that is referenced to a "technical ground". Basically this is a new proper ground that bonds the system ground to a new externally created ground (you get to drive rods into the earth) that is otherwise separate to ground that the rest of the building's power is bonded to. After that, everything connected to the balanced power is grounded to the technical ground via the ground connections on the supply. Cheater plugs are thrown away if they were in use, and all the usual correct grounding and balanced signal reticulation rules are used. The result is supposed to be a system where all the noise problems inherent in recording studio systems (and these can be a serious mess) can be eliminated, and a proper safe system created.

The supply includes its own GFCI, which is of course balanced relative to the technical ground. So, in principle, the entire system is safe.

So why is the device built as it is?
Interestingly they claim very high quality steel is used for the core. Which is odd. Usually you do that to improve frequency response. Which with a power isolation device is generally what you don’t want. Indeed Amir’s results show this. However the rationale seems to be that they don't want the transformer core to introduce distortions of the waveform itself. They trumpet a bifilar wound secondary the ensure avoidance of asymmetric waveform distortion. The device is designed from the outset not to filter external noise. So Amir's measurements actually confirm the manufacturer's design goals. This isn't a filter, and should not be judged as one.

The manufacturer's products do see use in professional recording and other professional audio applications. But not as a line filter, because it isn't one. Its entire job is to help manage grounding. The manufacturer's FAQ provides a detailed and pretty reasonable sounding set of how-tos to help debug and cure noise issues in a recording studio. In the end all the claimed sonic benefits come down to managing grounding and noise issues that result from them. No doubt, in a recording studio, with distributed sets of equipment all coupled together, grounding issues and noise is a very real problem.

Sold into domestic settings is much more problematic. Code requires that these devices are only used in properly supervised environments where there is a need for a technical ground. So clearly for a domestic setting these devices should not be used and they should not be sold into them. Without a proper technical ground installation they won't even work as designed to help with grounding.

 

[Frank Dernie]

Balanced power takes a 120 volt RMS incoming feed and produces two out of phase 60 volt feeds which gives you the same differential 120 volt. This is said to do all kinds of things from reducing noise to making your music sound better. From the company

I am gobsmacked.
I was told when in the USA on student exchange in 1970 that the reason 110 volts was used in the USA despite the large I squared R losses was safety, since the contacts are actually two 55V signals out of phase and 55V is unlikely to be fatal.
I saw some logic there and had no reason to doubt it until today 51 years later!
So in fact one of the mains connectors in the US is actually at , or near, Earth potential?

 

[GWolfman]

Dishonest company. Add that to my "never" list...

 

[Francis Vaughan]

since the contacts are actually two 55V signals out of phase and 55V is unlikely to be fatal.

This sounds a bit confused. As if the person telling this had mistaken the manner in which 110 volts is related to 220v and applied it again.
In the US houses are generally fed from one phase of the street mains, and a centre tapped transformer is used to create two 110v legs, 180 degrees out of phase, with the centre (neutral) bonded to ground. So the household runs 110v to power outlets, but has access to 220v for power hungry appliances.
In most respects it is similar to the three phase power those of us on 240v systems are used to - each phase is referenced to a ground bonded neutral, but they have a local 2 phase supply.
In a US house you could find two outlets that are on different phases and get a 220v feed, just as in a 240v 3 phase system, if you can find two outlets on different phases, you can get a 415v feed. Not recommended, but possible.

 

[Koeitje]

This is a high power unit designed to drive amplifiers and such as I quoted in the intro.

Plus the amplifier you are using to measure has less THD+N than a lot of DACs.

 

[amirm]

So in fact one of the mains connectors in the US is actually at , or near, Earth potential?

Yes. The neutral conductor ties in the main panel to a safety ground rod as a matter of fact.

 

[abdo123]

is it really difficult when you have a 1000000% markup to actually design a decent active noise cancellation adapter or something?

 

[Frank Dernie]

This sounds a bit confused. As if the person telling this had mistaken the manner in which 110 volts is related to 220v and applied it again.
In the US houses are generally fed from one phase of the street mains, and a centre tapped transformer is used to create two 110v legs, 180 degrees out of phase, with the centre (neutral) bonded to ground. So the household runs 110v to power outlets, but has access to 220v for power hungry appliances.
In most respects it is similar to the three phase power those of us on 240v systems are used to - each phase is referenced to a ground bonded neutral, but they have a local 2 phase supply.
In a US house you could find two outlets that are on different phases and get a 220v feed, just as in a 240v 3 phase system, if you can find two outlets on different phases, you can get a 415v feed. Not recommended, but possible.

Thanks.
We just have a single phase 240V supply here at my house (I checked for the purposes of how powerful an electric car charger I can have at home if I buy one).
In France the house was on a 3-phase supply with different phases feeding different parts of the house! One had to share the highest power consuming items between phases to avoid tripping the supply, the standing charge depends on the max kW you specify and it trips if you try to take more.

 

[gsp1971]

Amir will definitely be persona non grata at the next hi-fi event / show / convention.

 

[Francis Vaughan]

I'm curious as to whether the device came with any instructions?

Given what it is and how it is meant to be used it requires very specific installation and use - and expectations. So what do they say? I can't find instructions on the manufacturer's web site. There is a specification document for commercial/professional use. But for domestic use?

The document says this about rack mount units:

RACK-MOUNTED BALANCED POWER SYSTEMS

• Rack Mounted Balanced Power Systems shall be securely mounted within the equipment cabinet housing the electronics to be served. No part of the Balanced Power circuit shall be extended beyond the equipment cabinet via extension cord, raceway, surface mold or any other approved or non-approved method.
  
  
• The ground in the normal power outlet feeding the Rack Mounted Balanced Power System is the primary ground reference for this system. Receptacles feeding Rack Mounted Balanced Power Systems shall be Isolated Ground receptacles. Under no circumstance shall any type of “ground lifter”, three-to-wire adaptor, or pin lifters be allowed.

Overall my feeling is that the company making this has somehow got enmeshed in selling a perfectly sensible device into a market for which it is not intended and is unlikely to have any of the intended benefits. That isn't a good start.

 

[3125b]

How does that 1200W Hypex PSU not have PFC?
In the EU it’s required from 75W and up according to DIN EN 61000-3-2, I‘m sure the US has something like that too ...

 

[anphex]

It is a gigantic transformer:

This looks so comical that I find it hard to believe this is real.

 

[Grumpish]

Nearly 5K for a transformer is absurd - there are plenty of companies selling similar (without the snake oil audiophile label) for 1/10 of that. https://airlinktransformers.com/category/conditioning-balanced-power-supply. They need to be designed and built right as well, otherwise you could end up with no safety ground. If you really can can hear an improvement with something like this (or any other kind of fancy power cord or fuse) then there is something wrong with the design or components that have been used.

 

[GeekyBastard]

It entire job is to help manage grounding issues...

Ah, so it IS just an isolation transformer sold for 5K, that's nuts!

 

[restorer-john]

Yes. The neutral conductor ties in the main panel to a safety ground rod as a matter of fact.

Just as it does here on every house. (unless that house has three phase power for a big HVAC etc)

Our system is M.E.N. (multiple, earthed neutral).

But when I want to light up some star wars type 'light sabre' old fluorescent tubes, I take my son down to the park near us in summer, on a particular hill, when the power consumption is at peak and the 275kV lines droop just enough...

 

[Francis Vaughan]

Ah, so it IS just an isolation transformer sold for 5K, that's nuts!

Pretty much. They make some very specific claims about why their transformer is better, mostly to do with overload or peak power delivery and how well balanced the outputs are. Both claimed to improve ground noise. High quality core steel is eye wateringly expensive compared to normal power transformer stuff, but how much this justifies the price or makes a difference is another matter.
Setting up to test this could be done but isn’t trivial.