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Friday, May 29, 2015

ALIS-5SE Ultimate User Comments

Another testimonial has arrived last night from our buddy, John. John has been discussing audio transformers build methodology with us for quite some time. He's a veteran HIFI/music enthusiast. It's our honor to be able to let our ALIS-5SE Ultimate be a part of his audio system. We'd like to take this opportunity to thank him for allowing us to post his comment on ALIS-5SE Ultimate in our blog!



Quote (unedited):

Hi, Jolin and Ken. I hope all is well on your side of the world. How were your travels?

I want to tell you how much I am enjoying your ALIS-5SE Ultimate transformers in my 300B amplifier! I only have a few hours on them so far, but from the moment I installed them, I was very impressed with the sound.

I have been using Magnequest FS-030's in my 300B amp for maybe 20 years. I have tried other transformers from time to time, but the FS-030's have been a constant in that amplifier. I like their "voicing". Their response is weighted towards the low end of the spectrum. Bass is very solid and goes very low, but the highs are not as delicate and extended as they could be. I know that Mike from Magnequest designs his transformers very conservatively. They have lots of primary inductance, something like 30-35H, and low winding resistance. But this does make the physical size of the transformer quite large, which in turn causes it to exhibit higher parasitic capacitances and hence lower high frequency bandwidth. I'm sure you know how all that works!

When I installed the ALIS-5SE Ultimates, I heard a number of changes. First of all, and quite surprising to me, was the improvement in bass definition and detail. Although your transformers don't quite have the ultimate weight of the FS-030's, I can follow bass lines much more easily, and the pure extension is very good, despite your only having maybe 2/3 the primary inductance.

I am finding the high frequencies to be most appealing. I am hearing improved definition and transparency. Sonic images have more space and separation around them than I am used to hearing. There is an ease and naturalness that I really enjoy. I am also pleased to hear a reduction in upper midrange "glare", a touch of hardness that I would not have associated with the output transformers.  All in all, a very transparent and natural sound that I am looking forward to living with.

This is not to say that the FS-030's sound bad or substandard in any way. Every designer makes certain conscious choices on how to "voice" his/her product. Mike chooses lots of inductance and low DCR, whereas you guys have chosen to achieve a wider high frequency extension with modest inductance. I can see someone with, say, a single-driver full-range loudspeaker preferring the FS-030's, as they would balance each other well. In my case, my loudspeakers use high-efficiency pro drivers. I have good bass extension from 12" drivers in vented boxes. I now find the bass nicely balanced and "tuneful". My high-frequency compression drivers/horns are very sensitive and have very low distortion, so I am able to hear the higher-frequency attributes of your transformers quite clearly.

This is not a formal review by any means, just an email from a satisfied customer! I look forward to living with these wonderful transformers, as well as integrating more of your products into my system in the near future.

All the best!

JL

End Quote

P.S. - For those that likes heavy bass, we have another model: ALIS-5SE MK2 that is meant for high Rp (plate impedance) tubes. The bass will be much better if used with low Rp Triodes! Using ALIS-5SE MK2 will have very good bass extension and quantity at the expense of some very high frequency loss. Still, ALIS-5SE MK2 specifications is very, very decent!


* Pentode: 20-65kHz(-1dB)
* Triode connected Pentode: 10-40kHz(-1dB)
(Note: pure Triode will have much better / wider bandwidth!)

Click this link to jump to our ALIS Output Transformers: 
J&K Audio Design ALIS Output Transformers 

J&K Audio Design
5/30/2015

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

Saturday, May 23, 2015

R-core transformers


Introducing low cost R-core transformers! 

Textbook says (not us), the benefits of R-core transformers are, but not limited to:

  • Stray magnetic flux is low, x10 lower that EI transformer
  • R-core transformer is smaller than EI by 30%, slimmer by 40%, and lighter by 40% 
  • R-core transformer generates 50% lesser heat than EI transformer
  • R-core transformer generates lesser noise compared to EI or gapped core transformers
  • R-core is more reliable, easier to install and better stability than toroid transformer
  • Etc...
Well, a lot of the statements above are questionable since the properties depend on a lot of other factors too, but one thing for sure is that R-core does have its benefits and sound signature.

R-core transformer employes a circularly wound steel core. The primary and secondary coils are wound on it. Due to the minimal gap between the coils and core, the loss is very low. Also, annealing treatment can be applied directly to the core to condition it at its best magnetic state to reduce distortion.

Our R-core ranges from 10VA (~U$25) to 1250VA (~U$340) per unit, depending on customization. If higher capacity is needed, customers can go for toroid transformers or parallel R-core transformers to go to as high as 2500W. Such parallel usage would be for balanced isolation transformer where the +ve is by a 1250VA unit and the -ve is by another 1250VA unit to make 2500VA in total.

One good example would be to make isolation transformers with R-core transformers! Due to the low profile nature of the core and windings, it can be made very compact with very good electrical properties! 

On the other hand, those who does not prefer R-core or still do not believe in R-core can still go for single C core transformers. We are introducing the economical C core power transformers as well ranging from 5VA (~U$28) to 1600VA (U$460), depending on customization. Parallelism can be done to get 3200VA unit too if needed. 

Single C core transformer - horizontal version
Single C core transformer - upright version
 Email us for a quotation with your customization needs. 

J&K Audio Design
23/5/2015

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

J&K Isolation Transformer Review

Greetings followers! 

Apologies for not sharing more news in our blog. We've been quite busy lately with new orders + R&D on making our products better and better.

Still, we would like to share with you what our trial uses said about our audiophile isolation transformer (J&K Isolation Transformer). Check out the Whatsapp screen capture below! We can't be more happy about the loss. 

He had taken a unit of 1KVA fully built isolation transformer, with J&K DC blocker, plus 2 units of J&K noise eliminator integrated into the unit. He brought it home for almost a week and this is what he wrote to me. 


User Comments
Isolation transformer and ALIS-5SE Ultimate Output Transformer Shipment

We would like to thank our supporters for your orders too! It has kept us quite busy for weeks! For those that have not tried J&K isolation transformer and/or ALIS-5SE Ultimate output transformer for 2A3 or 300B tubes, you have no idea what you have been missing!

J&K Audio Design
5/23/2015

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.

Sunday, May 10, 2015

J&K on business trip

J&K guys are on business trip!

Production goes on as usual but customer service, email response, design services and more "high level" operations are on hold or slower until next week (16th May 2015).

J&K
5/10/2015

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.

Sunday, May 3, 2015

ALIS-5SE Ultimate Review

Nothing is more satisfying than reading good comments from our users online. Please click the below link to see (or to participate, ask questions, feedback, comment) the actual thread at diyaudio.com. 


Below are some screen captures from the original thread for your reading pleasure (at least is our reading pleasure. It is very well written. We simple love it. 

5/3/2015 - final comparison inserted at the bottom last image. Check it out!

ALIS-5SE Ultimate at diyaudio.com

ALIS-5SE Ultimate user comments
ALIS-5SE Ultimate Sound Description
ALIS-5SE Ultimate comparison with Tango XE-20S?
5/3/2015 - Final comparison of Tango XE-20S with ALIS-5SE Ultimate



We hope to see the comparison results with Tango XE-20S that is an Orient Hi-B C core OPT soon. It will be an interesting comparison. It will be clash of the Titan with a newbie. :)

J&K Audio Design
4/10/2015

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


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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.