Loth X JI 300 translation - Audio Note Singapore

Revue du Son et du Home Cinema, number 254, July/August 2001.
Audio Dossier, Tube Amplifiers.
Loth-X JI 300
An exceptional top-of-the-line unit for extracting the quintessence of the latest WE 300B
triodes.
Specifications
Integrated Amplifier
Nominal Power: 2 x 8 W/ 8 ohm or 16 ohm.
Sensitivity: 350 mV/10 k ohm.
5 high level inputs and monit.
8 and 16 ohm outputs.
Frequency Response
10 Hz – 30 kHz - arpox. 3 dB.
Harmonic Distortion
Equal to or smaller than 2%/1kHz.
Tubes
WE 300B x 2. 5865 and 5687 x 2.
Dimensions/Weight
430 x 245 x 370 mm. 22 kg.
Origin
Singapore/Korea
List Price: 54 900 F/ 8369 Euros (launching price).

Tips for Use
An amplifier, reserved for audio purists, especially for those who are fond of high-fidelity
speakers, particularly the famous Loth-X Polaris enclosures.
SINCE its founding in 1998 in Singapore, the Loth-X society has never ceased being
distinguished for the quality and originality of its creations, which have been consecrated
to the top of the line of the audio world. This old distributor of Lowther speakers,
unsatisfied with existing products, wanted to throw itself into the design and
commercialization of high fidelity speakers, then analog turntables, and finally tube
amplifiers, while all the while never deviating from its purist philosophy. They have
never flinched away from making heavy investments in chassis, networks, presses, and
tools for the manufacture of chassis, speakers, membranes, Alnico magnets, and of the
numerous items that make up their turntables. This perfectionist philosophy has borne
fruit. During the last Hi-Fi salon in Seoul in November 2000, the presentation of the
Silbatone C-102 preamplifier, battery powered and equipped with professional
potentiometers, was followed, over the course of the first three days, with the sale of ten
units. This is all the more impressive considering the hefty price tag of these units, which
is more than justified. Loth-X owes its excellent reputation to the competence of several
engineers, particularly Stephan Stamm for speakers. A small detail about the Loth-X
brand – the name is not derived from the English brand Lowther, but instead from the
given name of the company’s director, Mr. Lothar Sander.

JI 300: The Top of the Line
Products that are made with as much care as the Loth-X JI 300 are quite rare.
Accuphase, Nagra, Jeff Rowland, or Cello can be named as exceptions. The most
stunning piece of information is that the JI 300 is none other than the little brother of the
top-of-the-line Silbatone 300SE. The imposing chassis is not made of finely profiled
aluminium, but instead of massive blocks of machined aluminium. A high degree of
precision is omnipresent. Loth-X goes so far as to mount the command dials (entry
selector, 40-plot Tokyo-Ko-On attenuator) on ball bearings.
An examination of the interior is even more astonishing. The first thing we notice is the
presence of a large number of top-of-the-line components, designed and manufactured by
Loth-X: Slivered-mica condensers, anti-selftic coiled resistors, oiled-paper condensers,
gold double-sided circuit board, silvered connectors. The other big surprise is the very
heart of the chassis – an ultra-quick, ultra-stable power coupling. Its internal resistance is
50 times less than that of a bi-plate valve. This solution, according to Loth-X, is the best
approach apart from battery power.
The monotriode circuit delivers a nominal power of 8 W. It makes the best use of the
latest version of the WE 300B made by the Westrex Corporation. The input stage uses the
5965 double triode, with the second triode mounted in a cathodyne output. The 5687 is
likewise mounted in a cathodyne output. The output transformers, equipped with 8 and
16 ohm sockets, use flat silver wire. What luxury!
-Jean Hiraga

Sound Critique
Test no. 1
Ella Fitzgerald, “Reach for Tomorrow”, Verve Classic Compact, VSCD-4043.
J.H. The silky velvetiness of the medium and high-end registers is a stunning experience.
The spectral balance remains excellent, except for an extreme low-end that retreats a bit.
What a bouquet of qualities!
R.L. The listening experience strikes one with its ethereal and transparent character. The
sonic message is sought. We are incontestably very close to a certain sonic truth. The low
end seemed to me to be on the retreat.
Test no. 2
Mozart, Fantasia for piano, in D minor, Ivo Pogorelich, track 1, DG 437 763-2.
J.H. Sure, the first octaves seem a little light, but they are largely compensated for by an
exceptional richness of timbre. The felt of the hammers, the strings, all are analysed
under a magnifying glass.
R.L. The tonal rendition of the instrument is of the highest calibre. The realism of the
timbres will make you shiver. The left hand is light, perhaps a little too light.
Test no. 3
Applause tests, percussion, NRDS no. 10, tracks 14, 17, and 21.
J.H. There again, the bass comes out with a suggestion of lightness, but it’s largely
compensated for by the high definition. The bells are sublime.
R.L. The Loth performs miracles in terms of definition. It’s a magnifying glass of the
highest quality that forgives nothing. The only thing missing is a more consistent base.

Test no. 4
Mark Curry, It’s only time, “All over me”, Virgin CDVUS 49.
J.H. The slight lack of base in the bass and the boosted definition have the effect of
rejuvenating Mark Curry’s voice. The lesser analysed details are unusual.
R.L. Mark Curry is missing some thickness, but not any humanity. This phenomenon is
accentuated bye the analytic side in the high end of the spectrum.
Test no. 5
Johann Strauss, Egyptian March, Op. 335, Das Mikrofon, Tacet 17.
J.H. Without fear of being contradicted, we can speak of a truly rare level of transparency
here, especially on the part of the 300B that we thought we knew. It’s all at once ultradefined
and soft.
R.L. The tonal palette is quite diversified. Each instrument in the orchestra seems to have
rediscovered its true colour.
Measurements
Loth-X JI 300 Amplifier
No. 200/1603
Sensitivity: 350 mV
Nominal Power: 2 x 8 W/8 ohm.
Degree of Harmonic Distortion at:
2 W/40 Hz: 2.1%
2 W/1 kHz: 1.7%
2 W/15 kHz: 1.6%
Signal/Noise Ratio, unbalanced: 98 dB.
Time to Climb, 10 kHz square wave: 4.5 micro s.

Results: The power tension flattens out lightly superior at 420 V, the obtained nominal
power is in the order of 8 W. The degree of obtained distortion is linked to the absence of
C.R.
Sine wave shape at 1 kHz/2 W.
We obtained a signal devoid of parasites and instabilities thanks to the stabilized power
coupling. Predominance of paired harmonics.
Square wave shape at 40 kHz/ 2 W.
Results: The incline of the levels is normal, we encounter it in the vast majority of
monotriode mounts.
Square wave shape at 15 kHz/2 W.
Results: The response in the ultrasonic domain of the output transformer is due to the
formation of over-oscillations below 15 kHz.
Overall Evaluation
Jean Hiraga
Decidedly, Loth-X is a brand that never ceases to surprise us. Examined up close, this
amplifier is crammed with ideas, halfway between tradition and revolution. With the WE
300B on one side, an ultra fast power cut on the other, the whole thing is topped off with
some very rare and costly components (the Toko attenuator of the same version is sold in
Japan for more than 4000 F!). The important thing is to recognize that the result is
indisputably there: an unequalled richness of timbre. Only one weak point: a low end of
the spectrum that is a bit short, although it is rich in detail. Stunning!
Robert Lacrampe
This superb amplifier is more than stunning. It teems with cleverness, and will surprise
more than one audiophile who is used to the 300B. The abundance of harmonics and the
profusion of details are above the rest. It’s only missing a bit of weight in the bottom end

or it would be the set we would take with us to a desert island. It’s too bad that the price
tag, high but justifiably so, prevents us from bestowing our Recommendation.
Valuation
Subjective Dynamic 9/10
Definition 10/10
Stereophonic Effect 10/10
Set coherence 9/10
Price/quality Ratio 10/10
We liked:
The “wild” aspect of the concept, with totally stunning results to compensate.
We would have appreciated:
More power. More consistent bass register.