Customize Transformers

Customize Transformers

If you are planning to customize transformers for your project, you can contact us. We offer HIGH QUALITY reasonably priced high quality Z11 EI core (Japanese made) transformers custom winding services. We’ve just partnered with 2 master guru level transformer winder with over 30 – 40 years of winding experience to offer you this service. 

• Power transformer (any devices, not just audio equipment)
•  Isolation transformer
• Step-up or step-down transformer
•  Output transformer (power, pre, headphone output)
• Input transformer
• Inter-stage transformer
• Inductor / choke (grid choke, power supply choke, plate load choke, crossover choke (include multi-tap choke for tone adjustment – ex: Tannoy crossover, need a unit to reverse engineer)

Notes:

• Various outlooks / mounting style available, please send us pictures on how you want it to look like to avoid miscommunications.
• Black powder coating available for additional small surcharge.

We can customize transformers based on the cores you provide too, like C-core, double-C-core, R-core, amorphous core, nickel core and etc, except toroid core. If you want to repair your machines with toroid core, we will replace equivalent EI core for you.

We’ve received many cases where DIY audiophiles supply “Western Electric” iron cores salvaged from defective / salvaged equipment to be wound for their new projects. The tonality of these Western Electric cores is just way much better (or different) compared to the modern cores.  

We offer all sorts’ transformer repair services too on top of customize transformers. We will try out best (sometimes the damages are so severe that the burnt core is no longer usable) to rewind the transformer according to the original specifications and follow the original winding method to preserve the sound characteristics of the original transformer. 

A lot of vendors say that they’re experienced but when they meet with more complicated transformer (many or special windings), the repaired transformer will not be able to fit back to the chassis. Repairing and restoring transformer is a time & energy wasting job. Inexperienced people will not be able to properly restore it and the equipment will not be able to function properly or to be resold. Stability, reliability, power consumption and safety are not taken into consideration yet!

Reverse engineering service is offered to for obsolete transformers to reproduce or customize transformers for service and repair use. 

Important tip: to reverse engineer for repairing transformer, lots of patience and attention to details are required. One needs to record down how the transformer is winded, and what are the turns ratio and minute details to restore it to the original design. If it is not done so, the tonality will not be the same again. If one is careless during the reverse engineering process, the old windings will just break apart and the details cannot be retrieved anymore. Therefore, repairing such transformers takes a long time, much longer than the others that simply substitute with sub-par quality design. Every steps count! This is where all the REAL skills are. 

Transformer upgrade is available if your current equipment transformer is not up to the job or having problems – too hot, humming, rattling, excessive sag, intermittent failure, sparks or unsafe termination and etc. 

• Custom size transformers available for space constrained designs (good for modders or replacing damaged transformers in an existing chassis!)

Power conversion service is also available – change from 110-120Vac input to 220-240Vac, and vice versa, or any voltages you desire, for any types of cores. 

Email us for details and price quotation.

Our quality promises

A lot of suppliers can wind transformers. These transformers can all be used, but to what extent, is really questionable. The internal construction and the winding methodology is where it determines the safety, quality, reliability and end results. This is where the value of the high quality transformer lies.

• Wires are perfectly aligned.
• Inter-windings are perfectly aligned.
• Inter-windings are insulated.
• Z11 core material, made in Japan.
• Insulation material, imported from Japan, meet international standards.
• Correct wires types are used – right insulation ratings, gauge and specifications.
• Cores are perfectly aligned to increase efficiency and reduce wastage / heat.
• Correct or oversized core are used, no under-cut.
• High quality bobbins – nylon or equivalent grade.
• Tidy, clearly marked, safe and properly insulated and terminated taps.
• Conductive tape wrap around windings available for EI core transformers.
• Electrostatic shield available for power transformers.
•  Every step of the manufacturing processes is dealt with great care.
•  Guarantee no transformer mechanical hum or rattling.
• All being wound be 30-40 years’ experience professional master level winder.

You can measure the bandwidth using test equipment (oscilloscope, spectrum analyzer, LCR analyzer, audio analyzer and etc) to see how good our transformers are.

Indicative price (as reference, we will provide customization according to user request/specifications).

•  Precision Series Output Transformer  (PREMIUM)
• Provide your specifications and contact us for pricing.
• Frequency response: 
• Single Ended:
• 20Hz – 30kHz +/- 0.5dB
• ~5Hz - 100kHz +/- 1.5dB (usually is)
• Push Pull: 
• 20Hz - 30kHz +/- 0.4dB
• 10Hz t0 50kHz +/- 1.2dB
• High impedance design >10k, specifications will vary, contact us to customize.
• Depending on applications, transformers will be treated with wax or varnish soaked in vacuum chamber to draw out all the air to ensure total penetration, and baked to perfection.
•  If you need better specifications or customize to your listening taste, please let us know. We can do so for you with extra charge.

•  Miniwatt Series Output Transformer (budget)

• Vintage Series Output Transformer (standard)
  
  • Frequency response: 20Hz – 20kHz +/- 3dB or better
  • All transformers are soaked in varnish overnight and baked to dry. Some will have wax instead of varnish, depending on applications.
   
• Power Transformer
• ~U$0.50 to U$1.00 per VA, depending on complexity and finishing.
• Z11 core.

• Choke / Inductor
• Various values and sizes are available.
• Z11 core.

Our internal quality assurance is actually stricter than what we published here for our customers. We will ensure the tolerance is kept very tight. 

Safety & quality are our utmost priority. Pay for the quality, so that it can last longer, consume less energy and sound better! You save in the long run – just imagine what the ever increasing energy bills will cost you and how much you will save! It pays for itself in the long run! Your transformer will be FOC – free of charge eventually from the savings!

Our varnishing processes are not just dip the transformer in varnish and take it out immediately for drying. It is fully immersed overnight, left for air dry and then followed by baking to fully dry the unit. For the precision series, it is vacuumed to withdraw out all the trapped air totally. 

As all our transformers are meticulously made for quality excellence, it requires a lead time to get it completed. So, please order your transformers early. This is a true old school transformer making. Z11 core alone does not guarantee that it is of excellent quality. 

The internal winding quality is very important. The winding design will affect the transformer lifespan and power consumption. This is not to be omitted. Depending on complexity, sometimes It takes almost 1 day to complete a custom wound transformer. Our transformers are having 1 winding layer sandwiched with 1 layer of insulation film / paper! That’s where all the cost of workmanship (and quality) comes from!  

Not to forget, as our guru winders are considered not young anymore (what can we expect after 30-40 years of work experience), they will retire soon and being replaced by younger apprentice. Quality will still be excellent but it won’t be as perfect as what the experienced master winder can make. So, order them while we still can offer them. Once it’s gone, it’s gone forever. 

Sometimes people cut corners by looking for cheaper transformers. Do you believe this philosophy – what you pay is what you get? Nobody is going to make a loss for selling you their products. If it seems too good to be true, then don’t buy it. For sure something must be compensated and for transformers, it is what they use that scares you as it is not visually apparent to most users. Many factors can be compromised, for example:

• Iron core type / grade
• Insulation material quality / grade
• Winding quality
• Wire quality / specifications
• Bobbin quality
• Proper insulation and arrangement for output taps

Cheap versus good makes a huge difference! What’s the purpose to spend thousands of dollars one expensive power cord, just to be matched with a low quality transformer with wires that is 10’s of feet long or even longer.  

Important tip 1: overheated core (from wrong core material, undersized core, wrong wire size or etc) will make the insulation material degrade faster and therefore shorten the lifespan of the transformer! Have you seen a burnt transformer, or a transformer winding burst into flame? I’m sure you do not wish to witness that. 

Important tip 2: hire only reputable transformer guru to repair your transformers for OEM equipment to prevent the transformer being swapped with inferior core (There are such conmen out there, beware! Really cry no tears!) or the windings are not following the original design. The sound will end up to be totally mismatched between the original and the repaired transformer. Don’t save on quality. You are saving as a return! 

Transformer is the beeping heart of audio equipment. Selecting the right transformer is critical towards good sound. Don’t compromise the safety and quality on buying from unknown sources! Your family and own safety are the most important thing of all! 

We treat transformer as a piece of art and use our heart to design and consider all the parameters to make it an excellent transformer, not just quality, but the look as well! This will show our high product value and differentiation compared to other vendors. 

All our transformers are custom made for our customers. We can follow customer machine sizes, opening dimensions, mounting holes; voltage taps requirements, current requirements and various other criteria to design the various types of transformers. Customers can even select the types of wires to be used for input & output taps for best effect or fine tuning. So, contact us for details.

Don’t throw away your old gears or damaged transformers. Repair them. Save our mother earth by not wasting and recycling! We take pride in our transformers to meet your voltage and current specifications. Order with confidence! 

Please provide the following data when ordering (where applicable) for better estimation of price and size.

• Usage model / type
• Power ratings or output power
• Primary / secondary impedance
• To be used for what and how many tubes
• Intended steady state current / plate load current
• Class A,A, AB, Single Ended, or Push-Pull
• Desired size
• Outlook / style
• Compromises or special requests

·        P/S: we do not customize or repair toroid transformers

Distributors / resellers are welcomed.

Disclaimers:

• Price is right at the time of publication and may fluctuate according to the ever increase of iron core price, copper wire price and other material prices. Lock in early to prevent disappointment.
• Once sold, no returns accepted other than warranty returns. Please contact us prior to sending the items back for repair / servicing to discuss the details.
• We offer volume discounts. Please email for details. Due to the handmade and time consuming nature of our products, lead time may be longer for larger volumes.

Thank you! You deserve the best from us! Order early to avoid disappointment!

J&K Audio Design

18/12/2013

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