We can make anything that you can dream of. We are experts in arts of transformers making. We build all sorts of budget to exotic high end tube amplifiers. Just shoot us an email at jnkaudiodesign@gmail.com or fill in the form below. Email us even if what you want is not mentioned in our website. With regards from Penang, Malaysia!

Wednesday, May 18, 2016

Balanced Isotrans

Balanced isotrans - realize the full potential of your audio visual system by providing them with the clean balanced power!

Balance power (+/- 240Vac or +/-100Vac or any AC you fancy) eliminates ground loop and hum from your system. Isolation function removes all the noises from the incoming mains. The outcome - higher SNR for audio + video, darker background, lower noise floor, better contrast and separation. 

This unit uses the highest grade A1 SiFe Toroid, made in Japan. It runs cool (very low core loss), and does not have audible or mechanical hum, potted in epoxy with a very thick iron shield - absolute quietness.

J&K Isolation Transformer - MK2

Oversized 2.5KVA Toroid Isolation Transformer

Input current meter - output voltage monitor

Additional EMI/RFI filter for low noise (optional)

DC filter good for 5KW load

Ultra thick terminals for absolute current transfer

Upgrade options:
* Better input / output IEC sockets
* Furutech IEC inlets
* Audiophile DC filter
* Audiophile cables 
* Ground socket for connecting to 3io Black Box or any ground conditioners
* Etc

5/18/2016
J&K Audio Design

Saturday, May 14, 2016

Nanocrystalline Alloy Core


Why are we focusing on amorphous and Nanocrystalline core for our audio output transformers and chokes? Below materials from our iron supplier will paint you a picture of why it is a better material compared to ordinary Fe alloy cores.

Fe based amorphous alloy core

- Fe based amorphous alloy core is made of 80% Fe, 19% Si and some other minor compound. It has high magnetic flux saturation density value (1.54T). The permeability, excitation current, iron core loss and other magnetic properties are better than just normal SiFe core, especially the iron core loss (about 1/3 or 1/5 of grain oriented SiFe). It is used in distribution transformers, high power switching power supplies, pulse transformers, magnetic amplifiers, IF transformer and inverters largely, being suitable for 16kHz and below switching frequency.

Fe based nanocrystalline alloy core

- Fe based nanocrystalline alloy core is mainly consisted of Fe, with small quantity of Nb, Cu, Si and B. It is formed by a post processed rapid solidification process, as a amorphous form. These amorphous materials, after processed, can attain a crystalline form of about 10-20nm crystals, scattered all over the amorphous base, and named as nanocrystalline materials. 
- Nanocrystalline core has excellent magnetic properties: high magnetic flux saturation density value (1.2T), high initial permeability (8x10^4), low Hc(0.32A/M), low high frequency loss at high magnetic induction value (P at 0.5T, 20kHz = 30W/kg), with resistivity at 80uOhm/cm, much higher than Permalloy(50-60uOhm/cm), by longitudinal or transverse magnetization, can get high Br (0.9) or low Br (1000Gs). It is, as of now, the best compound materials, especially suitable for frequency range from 50Hz - 100kHz, the best being 20kHz - 50kHz. It is mostly used in high power switching power supply, inverters, magnetic amplifiers, high frequency transformers, high frequency converters, high frequency inductors, current transformers, leakage protection switch, common mode chokes.

J&K Audio Design
5/14/2016

Saturday, May 7, 2016

Coupling Transformer Interstage Transformer


Level 2 (medium-high end) Transformers
* Representative data but not comprehensive. Please email us if you do not find what you need.



ModelSpecificationsPrice
 L2-PRE626 Usage: input coupling, input step-up (no DC)
Imp: 600 Ohm: 26K Ohm
DC: 0mA, no DC allowed
Gain: 6.8  
Freq: 20Hz - 20kHz @-0.18dB
Freq: 5Hz - 50kHz @ -3dB
Loss: 0.25dB
Weight: ~6KG/pair 

* OFC copper wire, hybrid EI Permalloy core, potted in square grey case
* Good for input coupling, or input step-up to drive driver/power tubes (with capable drivers)  
U$490/pr
L2-PRE197A
L2-PRE246
Usage: preamp / linestage output transformer
Imp: 24K (6K+6K) Ohm: 600 Ohm
DC: 0mA, no DC allowed
Gain: 5:1

* L2-PRE197A freq: 25Hz - 30kHz @ -3dB (high impedance triode 6J8P)
* L2-PRE246 freq: 5Hz - 50kHz @ 3dB (low impedance triode 6SN7)

* For low impedance Triode, eg. 5687/6SN7, please use L2-PRE246 for better frequency response

Primary DCR: 1308 Ohm, Sec DCR: 62 Ohm
Primary DC: 20mA max, Sec DC: 30mA max
Output: 35V max
Loss: 0.6dB
Weight: ~6KG/pair 

* L2-PRE197A - improve over WE 197A. OPT with original WE 197A design is available too. 
* OFC copper wire, hybrid EI Permalloy core, potted in square grey case
* Good for input coupling, or input step-up to drive driver/power tubes (with capable drivers)
U$690/pr


ModelSpecificationsPrice
L2-IT35 (standard)
L2-OIT35 (oil filled)
Usage: (2A3) power tube driver power tube (interstage)
Power: 15W (20Hz, SE)
Imp: 3.5K: 1.5K+1.5K (6K); 1:0.66+0.66 (1.32)
DCR: pri 120 Ohm, sec 200 Ohm (sec in series)
DC: primary 110mA max,secondary 30mA + 30mA max (or 60mA paralleled) 

*Freq: 20Hz - 20kHz @-0.3dB (flat with 2A3 in circuit)
*Freq: 10Hz - 60kHz @-3dB (in circuit with 2A3) 
THD: <0.2% (at 1KHz, 2K Ohm load at 0dB) 
Loss: 0.3dB
Weight: ~9KG/pair 

* OFC copper wire, hybrid EI Permalloy core, potted in square grey case 
U$890/pr (std)
U$1590/pr (oil)
L2-IT45 (standard)
L2-OIT45 (oil filled)
Usage: (300B) power tube driver power tube (interstage)
Power: 20 (20Hz, SE)
Imp: 5K Ohm: 20K Ohm or 5K Ohm: 5K Ohm 
DCR: pri 100 Ohm, sec 400 Ohm (sec in series)
DC: primary 170mA max,secondary 30mA + 30mA max (or 60mA paralleled) 

*Freq: 20Hz - 20kHz @-0.3dB (flat with 300B in circuit)
*Freq: 10Hz - 60kHz @-3dB (in circuit with 300B) 
THD: <0.2% (at 1KHz, 2K Ohm load at 0dB) 
Loss: 0.3dB
Weight: ~10KG/pair 

* OFC copper wire, hybrid EI Permalloy core, potted in square grey case
U$990/pr (std)
U$1690/pr (oil)


J&K Audio Design
5/8/2016

Level 2 Push Pull OPT

Level 2 (medium-high end) Push Pull Transformers
* Representative data but not comprehensive. Please email us if you do not find what you need.


ModelSpecificationsPrice
 L2-40PQUADTube: KT66, EL34, 6CA7, 5881
Cont. Power: 40W(30Hz) Push Pull

QUAD II replacement OPT

* Follows original amplifier materials and method of windings. Primary DC resistance, primary inductance, size, mounting mechanism and size are according to the original design.
* Measured output transformer performance is better than original.  
U$790/pr





ModelSpecificationsPrice
*L2-35PP50
**L2-35PP55
***L2-35PP66
Tube: 2A3, KT66, EL34, 6L6, and etc
Cont. Power: 35W(30Hz) Push Pull
*Imp: 5K-UL-0, 0-4-8-16 Ohm (others, please email)
**Imp: 5.5K-UL-0, 0-4-8-16 Ohm (others, please email)
***Imp: 6.6K-UL-0, 0-4-8-16 Ohm (others, please email) 
Feedback tap: please email
DC: 125mA x2 max, unbalance DC <5mA max
Freq: 6Hz - 65kHz @ -3dB (in circuit)
Loss: 0.25dB
Weight: ~9KG/pair 
U$640/pr

* Potted in grey case with wiring turrets* OFC magnet wire, hybrid EI alloy core
* Flat frequency response from 10Hz - 30kHz 
* Low distortion, low core loss
* Customization - please email   


ModelSpecificationsPrice
L2-50PP50Tube: 2A3, 300B, KT88, and etc
Cont. Power: 50W(30Hz) Push Pull
Imp: 5K-UL-0, 0-4-8-16 Ohm (others, please email)
Feedback tap: please email
DC: 150mA x2 max, unbalance DC <6mA max
Freq: 6Hz - 50kHz @ -3dB (in circuit)
Loss: 0.25dB
Weight: ~12KG/pair (standard), ~15KG (oil filled)

* Potted in grey case with wiring turrets
* OFC magnet wire, hybrid EI alloy core
* Flat frequency response from 10Hz - 30kHz 
* Low distortion, low core loss
* Customization - please email   
U$990/pr (std)
U$1590/pr (oil)
L2-50PP55Tube: 2A3, 300B, KT88, and etcCont. Power: 50W(30Hz) Push Pull
Imp: 5.5K-UL-0, 0-4-8-16 Ohm (others, please email)
Feedback tap: please email 
DC: 150mA x2, unbalance DC <6mA
Freq: 6Hz - 65kHz @ -3dB (in circuit)
Loss: 0.25dB   
Weight: ~12KG/pair (standard), ~15KG (oil filled)

* Potted in grey case with wiring turrets
* OFC magnet wire, hybrid EI alloy core
* Flat frequency response from 10Hz - 30kHz 
* Low distortion, low core loss
* Customization - please email
U$990/pr (std)
U$1590/pr (oil)
L2-50PP60Tube: 2A3, 300B, KT88, and etcCont. Power: 50W(30Hz) Push Pull
Imp: 6.0K-UL-0, 0-4-8-16 Ohm (others, please email)
Feedback tap: please email 
DC: 150mA x2, unbalance DC <6mA
Freq: 10Hz - 50kHz @ -3dB (in circuit)
Loss: 0.25dB   
Weight: ~12KG/pair (standard), ~15KG (oil filled)

* Potted in grey case with wiring turrets
* OFC magnet wire, hybrid EI alloy core
* Flat frequency response from 10Hz - 30kHz 
* Low distortion, low core loss
* Customization - please email
U$990/pr (std)
U$1590/pr (oil)


J&K Audio Design
5/8/2016