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Saturday, May 3, 2014

Order Delivery

It is going to be a busy Sunday...

Z11 filament choke x 2, Z11 power transformers x 2
Mini amorphous EI output transformers, 1:5 input transformers, Z11 ESS DAC power transformers
Z11 10H 400mA choke x 2, 300B QCAMOPT-L01 OPT, Z11 filament power transformer
Z11 Precision Wind A2 60mA 5K:1+1 output transformer, Z11 Precision Wind 300B output trans



J&K Audio Design
4th MAY 2014

Product Lists  

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Level 3: depends on type, size and complexity. Email us for details.
Iso-trans: link 1, link 2
* Finished amplifiers, DACs, audio gadgets, upgrades and repairs - this is not our core business and we do it out of passion. We do not have fixed models, fixed price and we customize for each individuals. The sky is limit of creativity.  
* Our product lines are always improving and increasing. If you do not see what you want, contact us!  
* Please email for volume discounts, distributor and OEM pricing.

Amorphous Choke

Special introduction - we have been shipping lots of amorphous C core chokes and got really good feedback on how much improvement they bring to our customers!

Prequel: 
What are the ways of upgrading your existing amplifier, other than playing with interconnects, speaker cables, platform isolation, and various other tweaks?

For DIY-ers, they would say - just change the components! That, to them, would bring more significant changes than playing with external factors. With the same amount of $$$ used on cables or other tweaks, DIY-ers can upgrade their amplifiers substantially, really substantially!

Nowadays, interconnects and power cords cost over USD$1K-5K easily. Imagine what can be done with the same amount of money! One can use all silver internal wiring, all Mundorf Silver/Gold capacitors, branded resistors, BlackGate capacitors, and any audiophile components one can possibly imagine. USD$5K can almost (very close) buy a pure silver output transformer already!

Changing capacitors, resistors, internal wiring, mechanical components and such are pretty common nowadays. Today, I'm going to introduce you another modifications that will bring substantial ROI to your amplifier:
AMORPHOUS CHOKE!
  1. For amplifiers with only RC filter, add an amorphous choke!
    • Produces lower voltage + current ripple, lesser heat (more efficient), lower partnering capacitance needed.
  2. For amplifiers with normal choke, add an amorphous choke! 
    • Better micro-dynamics, micro-details, better filtration, lower noise.
  3. For amplifiers with DC filament supply, add an amorphous choke!
    • Natural slow start, protect your tube filament for longer life.
    • Others are same as above points #1 and #2.
  4. For amplifiers with resistive load, add an amorphous plate/anode choke! 
    • Higher efficiency - lower voltage drop.
    • Better AC reactance (higher load, better linearity!
  5. And many more! 
We have published only 1 size of DCAMC-M01 amorphous double C core choke but we can custom make other sizes too. Do let us know if you need other value chokes.

For USD$109 for an amorphous double C core choke, high ROI tweaks never come cheaper than this. Nowadays, even exotic capacitors can cost many times of such price. Now, start using more chokes in your amplifier design!

Some people talking about of amorphous chokes:

Amorphous Double C Core Choke (nickel steel alloy) – DCAMC-M01
This is made using 4 pieces of C-core per transformer, having 8 pieces altogether for a pair of high end amorphous double C core nickel steel alloy choke. The amorphous C core is very thin and extremely brittle. Please do not drop the transformer to prevent damage. Take precaution when installing the transformer.
  • Available types: air-gapped choke (various sizes within core permit able values)
  • Primary inductance: 8H
  • Primary current: 300mA maximum
  • Primary DCR: 70 Ohm
  • Weight: 1.2KG per piece
  • Size: 60mm x 75mm x 90mm



J&K Audio Design
3 MAY 2014

Product Lists  

Level 0




Level 3: depends on type, size and complexity. Email us for details.

Iso-trans: link 1, link 2
* Finished amplifiers, DACs, audio gadgets, upgrades and repairs - this is not our core business and we do it out of passion. We do not have fixed models, fixed price and we customize for each individuals. The sky is limit of creativity.  

* Our product lines are always improving and increasing. If you do not see what you want, contact us!  
* Please email for volume discounts, distributor and OEM pricing.

Friday, April 25, 2014

Nightshade Miniamp - 5687 GZ32

Nightshade Miniamp
5687 + GZ32
750~1000mW
RRP: RM4,500
Front View
Side view
Night view - 5687 is pretty bright!
Dim light view - still very nice!
High quality components!
Layout for shortest signal path and least interconnects!
  • Certified made in Japan Z11 low noise power transformer
  • Certified made in Japan Z11 power chokes x 2
  • Certified made in Japan Z6 output transformer
  • Tube rectified - GZ32
  • Made in UK internal wiring - OFC
  • Audiophile capacitors + resistors
    • Kiwame, Holco, Dale, PRP, hand matched
    • Elna, FT (Germany) capacitors
  • No capacitors in signal path - direct coupled
  • Simples topology - using 5687 as single/output tubes
  • High quality gold plated ceramic tube sockets
  • High quality 3mm turret boards 
  • Solid, full Aluminum chassis, 3-5mm thickness overall
  • Extended chassis support for absolute stability
J&K Audio Design
26 APR 2014

Product Lists  

Level 0

Level 3: depends on type, size and complexity. Email us for details.
Iso-trans: link 1, link 2
* Finished amplifiers, DACs, audio gadgets, upgrades and repairs - this is not our core business and we do it out of passion. We do not have fixed models, fixed price and we customize for each individuals. The sky is limit of creativity.  
* Our product lines are always improving and increasing. If you do not see what you want, contact us!  
* Please email for volume discounts, distributor and OEM pricing.

Nickel Ferrite Amorphous Output Transformer

Since I have more time this week, let me share some pictures of the 2 sets of poison that had gone to their new homes. :)

  • 1st pair - 2.5K:8R/16R for 2A3, using L01 (oversided) quad C core, luxury stuff! 
  • 2nd pair - 3.0/3.5K: 8R/16R for 300B, using L01 quad C core, tasteful!
  • Both nickel ferrite amorphous cores!

Depending on the packaging material, a layer of foam added to the binding posts to protect the pins.
Wrapped in foam, protected by another layer of foam before going into the 1st box.

1st box goes into the 2nd box, with lots of foam protection.
Output transformer - pair 1 - Singapore
Output transformer - pair 2 - Singapore again!




J&K Audio Design
26 APR 2014

Product Lists  

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Level 3: depends on type, size and complexity. Email us for details.

Iso-trans: link 1, link 2
* Finished amplifiers, DACs, audio gadgets, upgrades and repairs - this is not our core business and we do it out of passion. We do not have fixed models, fixed price and we customize for each individuals. The sky is limit of creativity.  

* Our product lines are always improving and increasing. If you do not see what you want, contact us!  
* Please email for volume discounts, distributor and OEM pricing.

Monday, March 31, 2014

Hitachi Metglas AMCC-400

Alright... I surrender! I will have this as special order item. I will build 2 types to try out - single ended and push-pull output transformers.

I've got enough mails asking about the previous post on Hitachi Metglass AMCC-400 C Core. It looks like we have a lot of DIY audiophiles with good audio sense, ears or taste that want these kind of high quality Amorphous C cores for their amplifiers. 

Now I've to make 2 new pairs of it to try myself before I can really offer output transformers based on the Hitachi Metglas material for sale. I'll need 8 sets of them make 2 pairs of double C core output transformers, using 2 sets each for a piece of output transformer.

Hitachi Metglas C Core in original packing materials.

Hitachi Metglass C Core revealed!

Why are they so good? A few reasons:

  • low core loss compared to silicon iron cores
  • high operation flux density - due to high saturation flux density
  • high operation temperature - class F insulation grade (155 degC)
Take a look at Hitachi Metglass & Finemet literature yourself. Oops, what is Finemet? It is the higher end range of Hitachi cores that is better than Metglass. It is super high end stuff that I will not go into. The Finemet core price is ~4x the price of Metglass where Metglass is already expensive enough.

I'm looking for brave souls to venture into Finemet core and order it from me, made with Precision Winding method for an ultra high end output transformer.


Alright, back to topic, the Hitachi Metglass materials will take a few weeks to arrive, and add another few weeks to experiment with this core before a final product can be ready for sale. For those eager to secure the units 1st hand, kindly place your order now to avoid disappointment.

There are some very limited pairs of used Hitachi Metglass AMCC-400 cores available to be used for this purpose. Do book them before they run out. This size of AMCC-400 cores will be able to produce 12W for single ended and 50W for push-pull, rated conservatively.


J&K Audio
31st MAR 2014

Product Lists  

Level 0

Level 3: depends on type, size and complexity. Email us for details.
Iso-trans: link 1, link 2
* Finished amplifiers, DACs, audio gadgets, upgrades and repairs - this is not our core business and we do it out of passion. We do not have fixed models, fixed price and we customize for each individuals. The sky is limit of creativity.  
* Our product lines are always improving and increasing. If you do not see what you want, contact us!  
* Please email for volume discounts, distributor and OEM pricing.


Friday, March 21, 2014

Ultimate Amorphous Core Output Transformer

We often got asked about what is our best output transformer available at our store, and how much would it cost to make a pair. My standard response would be, Precision Series winding method, amorphous dual or quad C core, silver wire primaries and secondaries.

How much would that cost? This is usually the follow up answer. We would say, it depends. Because, it really depends. It depends on what power/size and impedance he or she is looking for.

On our no.2 seat in the line, a pair of 300B single ended output transformers, I would guesstimate it to be at whopping of > USD$3000 or more. I'm dead serious. It's no.2 on the seat. I would not say who's no.1 as the sky is the limit. I challenge you to show me what's call no.1!

Recently I embarked on a journey to find out how much would I go in terms of making the ultimate (My ultimate of course, not yours! I believe you could be more extreme than me!) I'm going for the Precision winding method, amorphous double C core with copper magnet wire.

(Wait a minute, that's not extreme! One may say! Just wait and see!)

The extreme part is on the amorphous double C core itself. I'm gong to use Hitachi Metglass cores, with a size of AMCC-400! Some may still ask, what's so special about AMCC-400. I can tell you that it is simply HUGE! Single C-core of AMCC-400 size is already quite hefty. With double C-core of AMCC-400, it is humongous. If you want to be more extreme, go for quad C-core. I'm not going to do that as I would not be able to carry the damn amplifier when it is done.

A single C-core of AMCC-400 is 2820g. Double C-core would be 5650g, just the core itself, mind you. Added with the windings, frame and bobbin, it would be about 7Kg++, just for a single piece of the output transformer alone. This should get me to +/- 0.1dB at 20Hz at full power or more! Now you see what I mean?

Precision winding is already the ultimate. I like warmer tonality and therefore copper wires suits me more. If you like airy highs, then go for silver wires.

Let's talk about price. Hitachi Metglass C-core on AMCC-400 size is USD$568 per piece (2 C's). You can search for the price online and you might find cheaper source but it won't deviate very far. 4 C's are needed to create a double C-core and that would be USD$1136 a piece of output transformer. For a pair for stereo amplifier, that would be USD$2272, just for the cores alone. Shipping + taxes of importing the cores are NOT included yet, not to mention the price to ship the made transformers to you. 

Also, do we still have any guys that want silver wires with the cores I'm using? I'm waiting for your email. That's how far I would go. I'm not sure about you. Maybe 1 day someone would email me and ask for Precision Series Hitachi Metglass Quad C Core AMCC-400 Size Silver Wire Output Transformer. 

I'm real glad to build you one. The Number One! Don't worry, it would be as expensive (not even close!) as the top transformer from UK, that's £9,695 a piece. 

Maybe I should build my ultimate to try it out one day. Stay tuned. Who knows that might happen. Tube amp has always been limited by the quality of the output transformers. Why not change the equation for 1 time and see how it is like to be tube limited 1 day... 

P/s: 22 MAR 2014 - my vendor just offered me a batch of used AMCC-400 for half the price. I think I'm able to make 20 sets of 15W SE or 50W PP output transformers out of it. Now that's some good news.

J&K Audio Design
21 MAR 2014

Product Lists  

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Level 3: depends on type, size and complexity. Email us for details.
Iso-trans: link 1, link 2
* Finished amplifiers, DACs, audio gadgets, upgrades and repairs - this is not our core business and we do it out of passion. We do not have fixed models, fixed price and we customize for each individuals. The sky is limit of creativity.  
* Our product lines are always improving and increasing. If you do not see what you want, contact us!  
* Please email for volume discounts, distributor and OEM pricing.

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* Finished amplifiers, DACs, audio gadgets, upgrades and repairs - this is not our core business and we do it out of passion. We do not have fixed models, fixed price and we customize for each individuals. The sky is limit of creativity.

* Our product lines are always improving and increasing. If you do not see what you want, contact us!

* Please email for volume discounts, distributor and OEM pricing.