Core Power Equi=Core 1000 A heck of a deal...

By Jeff Dorgay

A few weeks ago, we did a very short, sweet “distilled” review of the Equi=Core 1000 power conditioner. If you look back at the reviews section of the site, we’ve reviewed the smaller Equi=Core 600 and the larger 1800.

Everything we’ve written about these two applies here. There are a number of ways to handle removing noise and artifacts from the AC line. And we can argue forever as to which works better – some manufacturers use moderately to extremely elaborate filter networks, some take the large balanced isolation transformer approach, while still others sprinkle pixie dust on things and call it good. PS Audio and a few others regenerate the power and use what is essentially a massive high current power amplifier, to recreate the sine wave. I’ve had great luck with the PS Power Plants over the years, but they are expensive.

Much in the same way some audio enthusiasts swear by a step up transformer for their Moving Coil phono cartridges, after trying nearly everything over the last two decades, there’s no more cost effective way to get better sound from the AC line than with a well designed balanced isolation transformer. This is the approach of the Equi=Core products.

My experience with balanced isolation transformers (and I always suggest going to the biggest transformer you can afford, because you can never have too much current capacity) has always been this is an approach that filters noise without sacrificing fine detail.

As with so many things Underwood has sent us, this product is an extreme value proposition, especially at the current $999 internet direct price. It’s 1000-watt capacity will not be enough for the biggest of power amplifiers, but at $999 each, you can buy one for your amp (seriously, go all the way and get the 1800 for your amp) and a 1000 for your front end components. And if you have to, or remain skeptical, start with your front end components.

The best way to see what this product can do is to listen carefully to a handful of tracks with solo vocals, solo acoustic instruments, or small ensembles. Though obscure (but you can find it on Qobuz) I love the Netherlands Wind Ensemble. These light, plucky tracks will really give you an idea if the audio signal is being harmed or distorted tonally. Add some of your favorite piano tracks (George Winston is always my go to – sappy but have been listening to these records for 40 years now) to evaluate the dynamic aspect of inserting something in the power line.

Five to ten minutes in, you should be able to hear what you need to hear. With the Equi=Core in place, backgrounds become more silent, which equals more dynamics, better low-level resolution, and none of the complex overtones that you’re used to with stringed or wind instruments are corrupted.

That’s all a power product needs to do – clean up the noise and do no harm. And the Equi=Core 1000 does a fantastic job. With 6 outlets on the back side, you should be able to plug everything into it with ease. If you’re using a modest power integrated amplifier, a single 1000 should handle your amp, a phono stage and a turntable. We firmly believe that power cables do make a difference, if you’re on a budget at the beginning of this journey, if you can – invest in one really good power cord from the wall to the EQ1000. That’s where you’ll get the highest performance gain.

Finally, as with the other Equi=Core products, the balanced isolation transformer has an even more noticeable effect with vacuum tube gear. Even our reference Nagra Classic Phono Preamp, which is very silent, is even more silent plugged into the Equi=Core 1000. It goes from hearing a little bit of noise when your head is close to the tweeter, to no noise. Our Line Magnetic LM-805 SET amp is lovely, but slightly noisy with a touch of hum. Again, nearly all of this is gone with the EQ1000.

How will you know you’ve gone too far? If you’ve gone way too far and overtax the current capability, the circuit breaker on the front panel will pop. It’s worth mentioning here that staffer Jerold O’Brien uses an Equi=Core 1800 in his main system, and on a recent lightning strike to the house, only the sacrificial breaker on the front panel was damaged (an easy fix) but his beloved ARC SP-10 mk 2 and D76 power amplifiers were unharmed. So we know for a fact that the Equi=Core stuff will protect your gear. If you don’t push the EQ1000 hard enough to blow the breaker, you will notice a subtle flattening of the soundstage. Should you get to this point, take a quick look at how much power the components you have plugged in draw. You’ll probably only notice it when you’re really playing your system at high level. Remember, think about that 1800 if you have a big amp, and/or really like to crank it up.

Where the 600-watt version of this product will probably be a front end device only, the 1000 has enough capacity to fit a wider range of systems. And they are great for video too – you’ll definitely see blacker blacks, and more dynamic range there as well.

Again, Core Power gets the job done right and without requiring you to cancel your vacation plans. Highly recommended.
$999 (current special internet pricing)


Amplification PrimaLuna EVO400 Integrated, Conrad-Johnson CAV 45mkII, Line Magnetic LM-805iA

Analog Source Luxman PD-171/Kiseki Purple Heart/Chord Huei phonostage

Digital Source dCS Vivaldi ONE

Speakers Zu Audio OMEN Dirty Weekend, GE Audio Teddy, Harbeth C7ES-3XD

Cable Cardas Clear, Tellurium Q Black Diamond