JLTi EL34 & KT88 Amps

133 Dalmeny Drive, Prestons NSW 2170, Australia +612-96074650 & 0412-203382

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Real Vs False Claims?

NOW A CHOICE OF TWO TUBE AMPLIFIERS -  KT88/120 & EL34

NOW MARK 2 & TUNG-SOL KT120 OPTION AVAILABLE

Price is based on $1045 incl. GST plus projected cost of importin4 stock Amplifier.

Generally around $2250 in total with KT120 Option. Please email me.

Please Note: KT88 Works Both as Integrated & Power Amplifier

CONCEPTUAL SCHEMATIC:

 


EL34 Now Available as Power Amplifier Only - See Below

Projected Price is based on $990 plus projected cost of import. Please email me.

NICE ONLINE REVIEW by Digital Audio Review

The First User Review

OR

 

"JLTi" EL34 and KT88 BASIC TUBE AMPLIFIERS

"JLTi" EL34 Power Amplifier Only - Save $100

Featuring "Virtual Triode Mode Operation" & "Induced Permeability" and more clever technology.

Hello, my name is Joe Rasmussen and I have an interesting story to tell. I am not known as a person disposed towards hyperbole, but I will start with a startling exclamation:

THE WORLD'S BEST SOUNDING AMPLIFIER !!! ???

Maybe not quite, but did that get your attention? But I assure you it is not as crazy as it sounds. At the very least, this amplifier will not only compete with amplifiers costing ten thousand dollars and more, but will downright embarrass most of them. Read on as this is an interesting and intriguing story.

Now I know what you are thinking, here we go again with the usual outrageous claims. Yet people who know me will tell you that I am not given to exaggerations, it is not my usual disposition. I stand by the following claims. But read on as a more complex story emerges as part of a unique plan.

The Plan: To take a mass-produced OEM type Chinese made amplifier with decent basic performance and reasonable components such as good transformers with good bandwidth. The Chinese can now do that better than anybody else and they can turn these out at a cost we cannot compete. But the sonic performance is generally less than desirable compared to the very best. But we are going to change that.

So rather than compete, take advantage of it. But alas, few are able to do just that. But we are! Some of you may have heard of Vacuum State situated in Switzerland and headed by Allen Wright who used to live here in Sydney. For 33 years I have been a collaborator with Allen and also part of a loosely organised international team doing much leading edge research, much of which is then shared.

We are now in a position to do something extraordinary.

Rebuilding: We can rebuild key aspects of a basic Chinese design using some leading edge technology. Crucial components are changed (no, not the usual parts substitution that everybody else does) and a special "Induced Permeability" module super-charges the output transformers, the output tubes are wired in "Super Linear Triode Mode", and much more. We are talking real 2008 tube technology here.

Input Circuitry: Now employs Constant Current Source technology and direct coupling minimises the need for coupling capacitors, only two per channel. Deceptively simple and yet lacking nothing in performance.

Output Stage: Super Linear Triode Mode - adds amazing dynamic and life to the music, for the first time we are able to make Pentodes behave as real Triodes. The problem, being the Screen electrode, is 'shadowed' in relation to the Anode and is thus hidden, making the tube perform as if the Screen electrode wasn't there. The result is nothing short of a revelation. Musical sounds will jump from your speakers like never before - and prove once and for all the dynamic and musical superiority of tubes over solid-state and transistors. The critical impedance match between the anodes of the output tube and the primary winding of the output transformer is now far more dynamically stable. It is not appreciated by many designers that this interface is actually a high-pass filter that needs to be kept at as low a frequency as possible and then kept there under transient conditions. The leading edge research done by Menno Vanderveen (www.mennovanderveen.nl) has clarified this condition and we can now take advantage.

  (Wish to thank Bill Perkins for his invaluable contribution.) 

No Negative FeedBack: As new type of Triode stage is far more dynamically stable and linear, negative feedback can be completely eschewed. Eliminated! This also means that the amplifier is totally stable and completely unflappable. Loop feedback around a bandpass device (which is what a transformer is) leads to time smear that can cycle through the loop many times. It may sound like it is tightening up the bass, but it ends up sounding flatter and the magic that is the midrange becomes subtly dried out. Feedback is not the answer and once the answer has been found, then feedback is not needed.

Induced Permeability: This technology was in fact patented during the Second World War and then subsequently forgotten. What a pity. According to our foremost researcher on tube transformers, Menno Vanderveen (from the Netherlands and designer for companies like Plitron), the major shortcoming of tube output transformers is the lack of Permeability at low signal levels, leading to lack of resolution in a similar way to DACs (Digital to Analog Converters) suffer from at low levels (this fact will stun quite a few pro tube aficionados). High Permeability cores can be used to offset the problem, but these saturate at about half the power and the so-called amorphous cores are very expensive indeed. A 50 Watt transformer will be derated to 25 Watts or it distorts badly.

THE SOLUTION:

 

The solution is highly imaginative; make use an unused portion of the transformers bandwidth (very high frequencies) and then excite the transformer at a specific level that does no damage to the speaker and yet is high enough to stop the Permeability sliding to dangerously low levels below that. We also do not suffer from saturation and poor power performance as the transformer is not derated. The module fitted is called an L.E.M., Linearity Enhancement Module, and the result is to induce Permeability so it never drops below our defined level.

The result is superior definition and a marriage made in heaven when combined with Super Linear Triode Mode.

This combination, the Super Linear Triode and the L.E.M. is the crux of the story here, taking a modest tube amplifier and make it perform like little else out there does.

New Input Selector: Cheap rotary switch is replaced with higher quality silver contact type.

New Volume Control: The silver-carbon "JLTi" pot is simply the best sounding potentiometer we know of. Virtually all pots sounds excessively coloured (plummy mid-bass is common and shut-in top octaves and less overall resolution) whereas the JLTi pot sound quality is close to high quality switched attenuators but at a fraction of the price.

New Input and Inter-Stage Wiring: Single core silver impregnated copper from OK Wire Company in the UK. This has also been cryoed.

New Front Panel: The original is not compatible with the JLTi pot (short shaft and needs spline type knob) and thus a new one is fitted. This now sports the JLTi logo.

How does one describe the sound? In many ways it is similar to what might be described as a Single-Ended sound, also called S-E. If that is the kind of sound you are into, then this is the Push-Pull amplifier that will change your mind about P-P amps. It has none of the downsides usually associated with P-P, but far more dynamic and has much greater sonic impact (single-ended has asymmetrical rise time that blunts transients but regular P-P sound less pure and coarse sounding - but this is not the case here).

While only rated 20 Watts per channel, many have commented that it sounds far more powerful than that. When compared with the Audio Research D125, the owner of the AR was surprised to hear it was only 20 Watts as he had expected 60-70 Watts (the AR will soon be on sale on eBay). It is clear that in sound systems that lacks genuine dynamics, listeners simply feel the need to turn up the volume to compensate for this lack. Is this is why we see 300 Watt amplifiers in cars and young drivers exposing themselves to hugely loud music?

But dynamics and loudness is not the same thing. Here we have an amplifier that uses technology that enables true dynamics and amazing impact at reasonable and realistic volume without the need to turn the volume up any further. For those limited to late evening low level listening, "this amp is a dream come true" (Mariusz Mugaj, Perth, WA). Only when you have heard this quality does it really become comprehensible. But in reality this ought not to surprise us as the sounds we hear in real life are just like that.

As we walk through the day we don't feel we need to turn up some imaginary volume control, do we? But when we get to a sound system we have this need to turn it up so far that we cannot hear someone right next to us speak? Yet when we go to a concert where acoustic instruments are played, and the sense of full emotional impact is there in abundance, and if our friend next to us starts to talk and he is clearly audible, we realise that the impact of what we hear is not entirely tied to the loudness we perceive. Yes, realistic volume and no more. The music will do the rest for us!

But we have not covered the majestic quality this amplifier has in portraying realistic images and full bodied sound and capturing the beautiful colours of real musical instruments. This is indeed a music lover's amplifier and not a "Hi-Fi" amplifier. The sheer "body" (or solidity of sound) it can produce will stun you, especially, but not uniquely, on voices, the sheer physical presence of Diana Krall (I'm less a Norah Jones fan, but will prove the same point) voice will say much more than any words here.

The top end is extraordinary and unravels much intricate details previously not heard. Most other amplifiers, regardless of cost and whether tube or solid-state, sounds positively coarse. Curiously, while revealing more details in the treble it is also much less bright sounding because it avoids the coarseness and instead replaces it with a remarkable smoothness, silkiness and exquisite air.

I will only be too pleased to demonstrate the amplifier, just call and make arrangements if you find yourself in the Sydney area. It is a real pleasure to be given an opportunity to play it in a very good system and hear comments like "amazing" and "chalk and cheese" and know that you are providing an experience that they will not easily forget. Not everything in life is about dollars.

Bring some CDs and/or SACDs that you are familiar with. I am sure that you will agree that this shows we are at the threshold of a greater appreciation of what is really climbing the mountain that is electronically reproducing the sound of real music. In the home, is this not the ultimate challenge for a music lover?

Joe Rasmussen

Custom Analogue Audio

 


First Review

I have had the amplifier now for 3 weeks in my system, build quality is nice and the Chinese have got that right. The glow from the tubes at night time is the best visual feature that only a valve amp can deliver. It also runs hot once its warmed up, as would one expect from a valve amplifier.

What is more important than the looks of the amplifier, how it sounds!!!

This is where the JLTi shows its true dynamic and musical Nirvana. Never in my wildest dreams I thought that 20 watts would deliver dynamics the way this tube amp does. Please note that I don't listen to it until 2 hours of warming up as it becomes warmer and more full bodied after this time than when it is  first switched on.

There is no need to turn the volume up, the musicality comes so effortlessly it is totally engaging and free from noise and grain or harshness. Joe promised this dynamic effortlessness and he did not exaggerate one bit. I am running in my system 86db speakers (Lenehan ML-1 Signature @ AUD $5000), so they are not highly efficient, yet no problem with getting loud levels with clear and engaging sound from 20 watts. (Are you sure it's only 20 watts, Joe? I think you should measure it again).

The bottom end has extension and body of a more powerful solid state amplifier, but it never sounds dry. The midrange is like sweet honey coming from my speakers. I have heard a lot of amplifiers in my system some as much as $10,000 but nothing as engaging as the JLTi EL34. The music just seems to flow without anything getting in the way. Joe said this was more like the characteristic of a Single-Ended Triode amplifier, that ability to let the music speak for itself and then get out of the way. Three things come to mind, texture, harmonic beauty and smoothness!

I was so impressed with the amplifier that I took it over to see a fellow audiophile, Richard, who is an ex Vice President of Audiophile Society of Western Australia. We ran the JLTi EL34 with his PROAC 3.5 Reference Speakers for six hours. The JLTi had better bottom end, more low end resolution and extension than his expensive Audio Research amp. Midrange was sweeter and top end less grainy. Soundstage and imaging is also right up there. Guess what? Richard now wants a JLTi EL34 configured as a power amp and Joe said he is working on it.

Value for money? In my opinion, it just takes on another meaning. Not often does a product such as the JLTi EL34 makes it to the listening room of an audiophile like me and then gets a chance to audition it against a much more expensive product like Richard's Audio Research, but I was lucky to have the chance. IT is a shame that others don't have the same opportunity to make this comparison  as this is an audiophile product with a price well below what one would expect to pay. For the audiophile or music lover that does get an audition, they will know what I mean.

MARIO
ROCKINGHAM WESTERN AUSTRALIA
0403714667..
 

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Last modified: Monday June 08, 2015

Just had a terrible thought. If "intelligent design" is unscientific, then who will design our audio equipment?