Kojo Technology virtual grounding plugs: Do they work on speakers?

I was given these for review by Kenix Chua of Begins Acoustic.

By Lam Seng Fatt

Ever since I heard the improvement in sound quality between a non-grounded and grounded speaker during a recent demo using AudioVector speakers at Audio Perfectionist (see https://www.av2day.com/2022/08/audiovector-qr7-floorstanders-launched-in-malaysia/) I had been keen to try grounding my speakers, but didn’t know how to.

Kenix Chua of Begins Acoustic gave me the opportunity to try it when she handed me three Kojo Technology Crystal Ep virtual grounding plugs on the last day of the Kuala Lumpur International AV Show last weekend. Two of them had spades while the third had an RCA plug. I was told to plug them into the black terminals of the speakers or an unused black RCA jack of the preamp, DAC or streamer.

When I reached home on Oct 30, I decided to try the Kojo Technology Crystal Ep plugs on my ATC SCM50 speakers and fixed them to the black terminals. It was quite easy to do an A-B test using songs from Diana Krall and Tony Bennett’s Love Is Here To Stay album streamed from TIDAL. I had spent three days at KLIAVS 2022 listening to all sorts of hi-fi and AV systems but when I heard what the Kojo Technology plugs did to the sound, I continued listening till the wee hours of the morning and the next day, I had transferred funds to Begins Acoustic and the plugs became a permanent part of the resident system.

The Kojo Technology virtual grounding plug is connected to the black terminal of the speaker.

I was quite surprised that the sound improved as the noise floor went lower and more details popped out from the mix. The bass also lost some ‘muddiness’ and became clearer and better defined. Surprisingly the soundstage became wider though there was not that drastic a change in depth. Overall, there was a cleaner sound with more clarity, especially in the bass region.

The thing is the Audiovector method of grounding their speakers is different as a wire is attached to the basket of the driver and then to the ground terminal on the speaker. From there you are supposed to plug in another wire and attach the other end to the ground pin of an unused electrical plug and fix it to the mains.

When I googled, I found out that a few other manufacturers offer grounding boxes which connect to speaker negative terminals. Entreq, however, requires connecting to the negative speaker terminals on the amplifier.

I tried that too with the Kojo Technology Crystal Ep plugs on the black terminals of the Bryston stereo power amp, but the result was a sound that was smooth but lacked ‘energy’ and dynamics.

Plugging to the black speaker terminals of the power amp resulted in a smooth but not dynamic sound.

The best way was to attach them to the negative terminals on the speakers. In fact, if you are thinking of upgrading your speaker cables, I would suggest you try this tweak first. The sound may improve so much that you may not go for the upgrade and save some money. The plugs cost RM800 each (RM1,600 for a pair) and this tweak may be cheaper than mid or high-level speaker cables.

So is it all snake oil? What is inside the Kojo Technology Crystal Ep plugs? I found this on the company’s website, but it’s in Japanese.

Using Google Translate, the Japanese website states: “The Crystal Ep is filled with Kojo Technology’s creative ideas and special dedicated capacitors that are responsible for technical elements, expanding and enhancing the GND plane (conductor surface area).

“High-purity aluminum foil processed into strips is used for the internal conductor of the special dedicated capacitor, and although the apparent surface area is only about 100 cm 2 (10 cm × 10 cm), the special etching treatment on the conductor surface turns it into a sponge. Numerous cavities resembling crystalline structures are formed. As a result, these innumerable cavities increase the conductor surface area, ensuring an effective area of 11,000 cm 2 (110 cm x 100 cm) inside Crystal Ep .”

The company also advises against two things — do not use it in a car as the vibrations may cause the screws to loosen. And the digital output signal may stop, depending on the type of digital audio player or smartphone you are using.

The plugs are modular in design.
You can screw two plugs together for better performance and the RCA cap can be plugged into an unused RCA jack on any component to act as ground.

The plugs are well made and are gold plated. They come in four types — RCA plugs, banana plugs, 3.5 mm stereo mini plugs, and spades which can be unscrewed from the body. In fact, two plugs can be screwed together for better performance. The RCA cap can be used to turn an unused RCA jack into a ground connection.

Kojo Technology Crystal Ep plugs are available from Begins Acoustic. Contact Kenix Chua at 012-6500610 for more details.

Stay Connected

Must Read

Related articles