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Tuesday, January 30, 2018

811 Output Transformer Review

Another user review of J&K Output Transformer - this time is for 811 tube. 

Advertisement time! 

1. We customize low to very high end, low to very high power transformers.
2. We accept individual retail and corporate orders.
3. We customize amplifiers, DACs, power conditioners and various audio gadgets (depending on our free time and available slot).
4. Email to order! Lead time is 4-6 weeks. To avoid the long wait, order early! 

Just a side note - is HIFI enthusiasts so into spending for HIFI that they cannot get a phone with better camera? (Just kidding!).

Here goes another user feedback in USA:

The sound is awesome, I have monblocks, so I can do A/A testing. I changed on one amp, and my wife me tested some mono recordings..

with J&K it was like a thick veil got lifted, the musical details increased on all spectrum of frequencies, it was just amazing..

Now to change my next amp in 2 weeks when I am back from my travels..

Attached is a picture of the new output transformer in a separate chassis on the 2nd shelf


Schematic shown is not for commercial purposes.

We will try to put in more post this year... we hope. 

J&K Audio Design

Transformer upgrades with J&K ultra isolation transformer

Another great testimonial from our customer using our J&K Ultra Isolation Transformer - a real paying user feedback, rather than bogus paid reviews on blogs or magazines. 

Rich has been replacing all his transformers on his existing HIFI equipment with our Ultra Isolation Transformers. 

* Replace existing transformer with ultra isolation transformer
* Separating critical power rails to separate ultra isolation transformer
* Upgrading super critical power rails with OCC made ultra isolation transformers
* and many more... 

Without further ado, here goes the feedback from Rich. This is just the tip of the iceberg on the upgrades he had done to his HIFI and Home Theater gears. 

Auralic Vega DAC upgraded power supply with J& K Discrete Ultra ISO transformers replacing original toroid. Now front-ended by two stages of balanced Ultra ISO transformers for each of the three  secondaries in the Vega. Since upgrading the Crystek clock to the Pulsar, the lowered noise can really show what the clock can do for cleaning up transients, illuminating blur, spaciality/imaging and a very natural listening experience. J&K Ultra Transformers mounted in the silver enclosures on top of the Vega.
Also using two Ultra ISO stages for both the Uptone Audio USB Repeater and Antipodes Music Server.



Main 240VAC Distribution Hub for front-end components

- Preamp
- Music Server
- USB Regenerator
- Home Theater Processor

Fused 240VAC mains input into overbuilt J&K Audio-inspired DC blocker with fused 240VAC feeds to six external Ultra ISO balanced secondary Transformers for source components. Voltage (240V) display on front panel.
500W OCC wound 120VAC balanced secondary Ultra to three feeds for separate OCC wound Ultras for front-end analog circuits.
All power feeds to the system are now balanced.

Apologies for not posting that often. We are super busy with orders. 

J&K Audio Design

Wednesday, December 20, 2017

OCC Transformers

Greetings J&K followers! 

Apologies for not posting for some time. Busy, busy, and busy... that's what's left in our life! 

We didn't intend to post but we can't resist to do so since we have to take some pictures for one of our customers locally. He had ordered a set of unique transformers for his preamp - OCC copper power transformers, OCC copper filament transformers, and OCC copper chokes! 

We have always been a producer of high quality transformers. We can't resist the opportunity to promote OCC based transformers! Most of the time, OCC are used only in speaker cables, interconnects and power cords, but why not transformers? 

For us, OCC output transformers are quite common. OCC power transformers and chokes are rare, although not uncommon actually. We've made quite a lot of OCC ultra isolation transformers and output transformers for a few customers based in U.S.A. 

What are the benefits of OCC based transformers? From electrical properties perspective, they have lower DCR compared to standard magnet wires - lower impedance. The insulation paint is a few magnitude better than the standard ones too - longer life! 

Based on our listening tests, and feedback from customers, are that OCC copper transformers have smoother highs, more extended in mid-low bass and more refined in mids + highs. In overall, they are well worth the money spent compared to spending them on power cords, interconnects or speaker cables IMHO. The length used in transformers alone would explain why the differences are more significant compared to exterior cables. If you are already using OCC cables, investing in OCC transformers are a must in order to fully exploit the goodness of OCC wires.

Post-script: We are starting to explore OCC silver cables. We have limited stock of OCC silver wires ordered for a customer. There should be some leftover that can be used for a limited range of transformers. For those that could not fit what we have, we are very sorry that we still need some time to stock up more OCC silver wires (raw OCC silver wires are ultra expensive. The finished OCC silver transformers will be pricey.). If you are interested in OCC silver wires made transformers, drop us a mail and we shall see if something can be made just for you. 

Till then!

We wish you a very Merry Christmas, and a Happy New Year! 

J&K Audio Design

Monday, November 6, 2017

Penang flood

Penang island just experienced the worst flooding in the decade, perhaps even century! Georgetown had became Teh Tarik Town as most of the streets were flood with orange colored water from the downpour over the last weekend. Some areas even had chest deep water level. 

A lot have lost their homes, valuables, vehicles, and worst, some had lost their love ones. We're among the lucky ones where our operations and staffs are only slightly affected. We suffered losses due to damaged raw materials and finished goods. Still, these are only monetary losses. Thank god for that. Undelivered orders will be delayed as affected units will be scrapped and redone due to this natural (or man made even - global warming!) disaster.

Still, we must not forget the unfortunates and we pray deeply for them. 

Attached below is just the tip of the iceberg on how Georgetown was affected.

God bless the Penang and all flood victims. 

J&K Audio Design

Friday, November 3, 2017

GM70 Amplifier Review

GM70 tube amplifier review (a short one).

Domnic uses full set of transformers from J&K Audio Design - the GM70 output transformer, separate power transformer for B+ and filament transformers. 

Enjoy the pictures - very nicely done!

Short and sweet comments from Domnic!

The hum & hissing are not related to the transformers but the design of the amplifier. After several emails between Domnic and us, this issue is fixed by adding some additional circuit to the amplifier. The amplifier is as quiet as the deep wide universe now, and he's a very happy camper!

Some GM70 amplifier internal picture for those more technical minded. A lot of audiophile components are used, such as Mundorf electrolytic capacitors, Jensen PIO coupling capacitors, Kiwame carbon composition resistors and of course, full set of J&K transformers.

Again, this is as honest as it can be - review from real user! No alteration of the customer posts have been made.

J&K Audio Design

Saturday, October 28, 2017

Out of office

Hi guys,

We will be out of office for 1 week, on a business trip to China, starting 29th Oct'17.

Email access and response will be very slow as a lot of the websites we use are blocked in China, such as Google based applications and Facebook.

Apologies for the late responses and any inconveniences caused is very regretted.

We will get back to you once we're back to office week after next. 

J&K Audio Design

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