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Thursday, August 25, 2016

HIFI Ground Box Review

We've received another stunning review from! Click the link below to get to know more about it!

Link to the ground box - 3io's BlackBox!

This unique ground box is ONLY available at J&K Audio Design and not anywhere else in the whole world. It is made with unique passive electronic circuit that works indefinitely. It is not the mineral based grounding box that is flooding the market now with lots of clones from Hong Kong and China, which may or may not work. 


Hear the Unheard!
J&K Audio Design

Thursday, August 18, 2016

3io Blackbox Review

Another stunning REAL user review from our audio transformer customer, not some paid write up or review! 

* Connect to phono ground 
* Connect to mains socket
* Connect to power conditioner
* Connect to power strip
* Connect to grounding post of equipment

3io's Blackbox

*** Start of review *** 

Hi, Ken and Jolin.

I'm angry. I like audiophile "accessories" as much as the next person. But when a manufacturer claims to "control a quantifiable amount of free electrons", my eyes glaze over. It's just this type of audiophile hyperbole that gives us all a bad name. Enter J&K's 3io BlackBox.

Let me offer a bit of background. I'm an electronics engineer by day and a hard-core DIY'er by night. I designed and built virtually all of my audio equipment myself. I have nearly 30 years of experience doing so. My system is vinyl-based, and all of my electronics use vacuum tubes with the occasional solid-state augmentation. My loudspeakers use pro drivers and a high-frequency horn.

I know the sound of my system quite well. Others have described it as big- and clear-sounding. It has slowly evolved over time to where it stands today. It is stable with no audio "surprises" when the music comes out. And music does indeed "come out", at least to these aging ears.

I recently had the opportunity to install a new phono cartridge, and I've been listening to it quite a bit. I felt that I had zeroed in on the characteristic sound of this cartridge, and I was pleased. I then received an email from J&K asking if I would like to audition the afore-mentioned 3io BlackBox, which was in the US for review. I know J&K make good stuff; I use and have heard several of their output transformers, so I know they can hear as well. Why not, I reasoned, setting aside my engineering sensibilities.

I figured the best place to start would be in my phono stage. I ran a clip-lead from the 3io BlackBox to the ground post on my phono preamp and sat down to listen. My mental notes go something like this:

"Hmm. The cartridge must still be breaking in. Sounds quite a bit nicer than last night."
"Gee, the bass has really tightened up!"
"Wow, listen to the separation of the instruments in the background!"
"It's like the singer took a step forward and the instruments in back spread out."

With trepidation, I started to wonder if the BlackBox had anything to do with it, so I disconnected it. It's as if a gentle haze had now settled in over the sound field, slightly but audibly affecting the overall system definition. Bass became a little "warmer" and things just seemed to get a bit more congested. "This can't be", I said to myself. I re-connected the BlackBox to the phono preamp, and the previous sense of clarity was restored.

I have confirmed to my own satisfaction that this 3io BlackBox has obvious benefits. Admittedly, its effect is pretty subtle, but not so subtle that it isn't plainly audible after a short period of relaxed listening. Its presence did not immediately announce itself; if it had, I would have been skeptical. I've learned that changes that jump out at you rarely prove to be improvements over the long term. It's the kind of change you'd hear moving from a $2000 phono cartridge to a $4000 one, and there are a lot of $2000 cartridges that I could live with. This 3io BlackBox brings the kind of improvement that I think most audiophiles and music lovers will appreciate.

No, it's not a magic clock or a fancy rock. Maybe there is benefit to harvesting all those free electrons polluting the grounds of my systems. But I'm mostly angry that my rational side doesn't understand the underlying technology. But at this price, who's complaining? I'm keeping the review sample.

Nice work, guys!

*** End of review ***

Hear the Unheard!
J&K Audio Design

Monday, August 8, 2016

Audiophile DC Blocker Review

Nothing makes us happier to receive REAL user reviews for our DC blocker. 

The DC riding on his mains are giving him some issues and he requested for a pure DC blocker, without any noise filters and other functions with the DC blocker. The money saved are used to upgrade to better components for the DC blocker, and therefore better sound quality is achieved.

Hear the unheard.

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